What is a scientific hypothesis?

It's the initial building block in the scientific method.

A girl looks at plants in a test tube for a science experiment. What's her scientific hypothesis?

Hypothesis basics

What makes a hypothesis testable.

  • Types of hypotheses
  • Hypothesis versus theory

Additional resources

Bibliography.

A scientific hypothesis is a tentative, testable explanation for a phenomenon in the natural world. It's the initial building block in the scientific method . Many describe it as an "educated guess" based on prior knowledge and observation. While this is true, a hypothesis is more informed than a guess. While an "educated guess" suggests a random prediction based on a person's expertise, developing a hypothesis requires active observation and background research. 

The basic idea of a hypothesis is that there is no predetermined outcome. For a solution to be termed a scientific hypothesis, it has to be an idea that can be supported or refuted through carefully crafted experimentation or observation. This concept, called falsifiability and testability, was advanced in the mid-20th century by Austrian-British philosopher Karl Popper in his famous book "The Logic of Scientific Discovery" (Routledge, 1959).

A key function of a hypothesis is to derive predictions about the results of future experiments and then perform those experiments to see whether they support the predictions.

A hypothesis is usually written in the form of an if-then statement, which gives a possibility (if) and explains what may happen because of the possibility (then). The statement could also include "may," according to California State University, Bakersfield .

Here are some examples of hypothesis statements:

  • If garlic repels fleas, then a dog that is given garlic every day will not get fleas.
  • If sugar causes cavities, then people who eat a lot of candy may be more prone to cavities.
  • If ultraviolet light can damage the eyes, then maybe this light can cause blindness.

A useful hypothesis should be testable and falsifiable. That means that it should be possible to prove it wrong. A theory that can't be proved wrong is nonscientific, according to Karl Popper's 1963 book " Conjectures and Refutations ."

An example of an untestable statement is, "Dogs are better than cats." That's because the definition of "better" is vague and subjective. However, an untestable statement can be reworded to make it testable. For example, the previous statement could be changed to this: "Owning a dog is associated with higher levels of physical fitness than owning a cat." With this statement, the researcher can take measures of physical fitness from dog and cat owners and compare the two.

Types of scientific hypotheses

Elementary-age students study alternative energy using homemade windmills during public school science class.

In an experiment, researchers generally state their hypotheses in two ways. The null hypothesis predicts that there will be no relationship between the variables tested, or no difference between the experimental groups. The alternative hypothesis predicts the opposite: that there will be a difference between the experimental groups. This is usually the hypothesis scientists are most interested in, according to the University of Miami .

For example, a null hypothesis might state, "There will be no difference in the rate of muscle growth between people who take a protein supplement and people who don't." The alternative hypothesis would state, "There will be a difference in the rate of muscle growth between people who take a protein supplement and people who don't."

If the results of the experiment show a relationship between the variables, then the null hypothesis has been rejected in favor of the alternative hypothesis, according to the book " Research Methods in Psychology " (​​BCcampus, 2015). 

There are other ways to describe an alternative hypothesis. The alternative hypothesis above does not specify a direction of the effect, only that there will be a difference between the two groups. That type of prediction is called a two-tailed hypothesis. If a hypothesis specifies a certain direction — for example, that people who take a protein supplement will gain more muscle than people who don't — it is called a one-tailed hypothesis, according to William M. K. Trochim , a professor of Policy Analysis and Management at Cornell University.

Sometimes, errors take place during an experiment. These errors can happen in one of two ways. A type I error is when the null hypothesis is rejected when it is true. This is also known as a false positive. A type II error occurs when the null hypothesis is not rejected when it is false. This is also known as a false negative, according to the University of California, Berkeley . 

A hypothesis can be rejected or modified, but it can never be proved correct 100% of the time. For example, a scientist can form a hypothesis stating that if a certain type of tomato has a gene for red pigment, that type of tomato will be red. During research, the scientist then finds that each tomato of this type is red. Though the findings confirm the hypothesis, there may be a tomato of that type somewhere in the world that isn't red. Thus, the hypothesis is true, but it may not be true 100% of the time.

Scientific theory vs. scientific hypothesis

The best hypotheses are simple. They deal with a relatively narrow set of phenomena. But theories are broader; they generally combine multiple hypotheses into a general explanation for a wide range of phenomena, according to the University of California, Berkeley . For example, a hypothesis might state, "If animals adapt to suit their environments, then birds that live on islands with lots of seeds to eat will have differently shaped beaks than birds that live on islands with lots of insects to eat." After testing many hypotheses like these, Charles Darwin formulated an overarching theory: the theory of evolution by natural selection.

"Theories are the ways that we make sense of what we observe in the natural world," Tanner said. "Theories are structures of ideas that explain and interpret facts." 

  • Read more about writing a hypothesis, from the American Medical Writers Association.
  • Find out why a hypothesis isn't always necessary in science, from The American Biology Teacher.
  • Learn about null and alternative hypotheses, from Prof. Essa on YouTube .

Encyclopedia Britannica. Scientific Hypothesis. Jan. 13, 2022. https://www.britannica.com/science/scientific-hypothesis

Karl Popper, "The Logic of Scientific Discovery," Routledge, 1959.

California State University, Bakersfield, "Formatting a testable hypothesis." https://www.csub.edu/~ddodenhoff/Bio100/Bio100sp04/formattingahypothesis.htm  

Karl Popper, "Conjectures and Refutations," Routledge, 1963.

Price, P., Jhangiani, R., & Chiang, I., "Research Methods of Psychology — 2nd Canadian Edition," BCcampus, 2015.‌

University of Miami, "The Scientific Method" http://www.bio.miami.edu/dana/161/evolution/161app1_scimethod.pdf  

William M.K. Trochim, "Research Methods Knowledge Base," https://conjointly.com/kb/hypotheses-explained/  

University of California, Berkeley, "Multiple Hypothesis Testing and False Discovery Rate" https://www.stat.berkeley.edu/~hhuang/STAT141/Lecture-FDR.pdf  

University of California, Berkeley, "Science at multiple levels" https://undsci.berkeley.edu/article/0_0_0/howscienceworks_19

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Home » What is a Hypothesis – Types, Examples and Writing Guide

What is a Hypothesis – Types, Examples and Writing Guide

Table of Contents

What is a Hypothesis

Definition:

Hypothesis is an educated guess or proposed explanation for a phenomenon, based on some initial observations or data. It is a tentative statement that can be tested and potentially proven or disproven through further investigation and experimentation.

Hypothesis is often used in scientific research to guide the design of experiments and the collection and analysis of data. It is an essential element of the scientific method, as it allows researchers to make predictions about the outcome of their experiments and to test those predictions to determine their accuracy.

Types of Hypothesis

Types of Hypothesis are as follows:

Research Hypothesis

A research hypothesis is a statement that predicts a relationship between variables. It is usually formulated as a specific statement that can be tested through research, and it is often used in scientific research to guide the design of experiments.

Null Hypothesis

The null hypothesis is a statement that assumes there is no significant difference or relationship between variables. It is often used as a starting point for testing the research hypothesis, and if the results of the study reject the null hypothesis, it suggests that there is a significant difference or relationship between variables.

Alternative Hypothesis

An alternative hypothesis is a statement that assumes there is a significant difference or relationship between variables. It is often used as an alternative to the null hypothesis and is tested against the null hypothesis to determine which statement is more accurate.

Directional Hypothesis

A directional hypothesis is a statement that predicts the direction of the relationship between variables. For example, a researcher might predict that increasing the amount of exercise will result in a decrease in body weight.

Non-directional Hypothesis

A non-directional hypothesis is a statement that predicts the relationship between variables but does not specify the direction. For example, a researcher might predict that there is a relationship between the amount of exercise and body weight, but they do not specify whether increasing or decreasing exercise will affect body weight.

Statistical Hypothesis

A statistical hypothesis is a statement that assumes a particular statistical model or distribution for the data. It is often used in statistical analysis to test the significance of a particular result.

Composite Hypothesis

A composite hypothesis is a statement that assumes more than one condition or outcome. It can be divided into several sub-hypotheses, each of which represents a different possible outcome.

Empirical Hypothesis

An empirical hypothesis is a statement that is based on observed phenomena or data. It is often used in scientific research to develop theories or models that explain the observed phenomena.

Simple Hypothesis

A simple hypothesis is a statement that assumes only one outcome or condition. It is often used in scientific research to test a single variable or factor.

Complex Hypothesis

A complex hypothesis is a statement that assumes multiple outcomes or conditions. It is often used in scientific research to test the effects of multiple variables or factors on a particular outcome.

Applications of Hypothesis

Hypotheses are used in various fields to guide research and make predictions about the outcomes of experiments or observations. Here are some examples of how hypotheses are applied in different fields:

  • Science : In scientific research, hypotheses are used to test the validity of theories and models that explain natural phenomena. For example, a hypothesis might be formulated to test the effects of a particular variable on a natural system, such as the effects of climate change on an ecosystem.
  • Medicine : In medical research, hypotheses are used to test the effectiveness of treatments and therapies for specific conditions. For example, a hypothesis might be formulated to test the effects of a new drug on a particular disease.
  • Psychology : In psychology, hypotheses are used to test theories and models of human behavior and cognition. For example, a hypothesis might be formulated to test the effects of a particular stimulus on the brain or behavior.
  • Sociology : In sociology, hypotheses are used to test theories and models of social phenomena, such as the effects of social structures or institutions on human behavior. For example, a hypothesis might be formulated to test the effects of income inequality on crime rates.
  • Business : In business research, hypotheses are used to test the validity of theories and models that explain business phenomena, such as consumer behavior or market trends. For example, a hypothesis might be formulated to test the effects of a new marketing campaign on consumer buying behavior.
  • Engineering : In engineering, hypotheses are used to test the effectiveness of new technologies or designs. For example, a hypothesis might be formulated to test the efficiency of a new solar panel design.

How to write a Hypothesis

Here are the steps to follow when writing a hypothesis:

Identify the Research Question

The first step is to identify the research question that you want to answer through your study. This question should be clear, specific, and focused. It should be something that can be investigated empirically and that has some relevance or significance in the field.

Conduct a Literature Review

Before writing your hypothesis, it’s essential to conduct a thorough literature review to understand what is already known about the topic. This will help you to identify the research gap and formulate a hypothesis that builds on existing knowledge.

Determine the Variables

The next step is to identify the variables involved in the research question. A variable is any characteristic or factor that can vary or change. There are two types of variables: independent and dependent. The independent variable is the one that is manipulated or changed by the researcher, while the dependent variable is the one that is measured or observed as a result of the independent variable.

Formulate the Hypothesis

Based on the research question and the variables involved, you can now formulate your hypothesis. A hypothesis should be a clear and concise statement that predicts the relationship between the variables. It should be testable through empirical research and based on existing theory or evidence.

Write the Null Hypothesis

The null hypothesis is the opposite of the alternative hypothesis, which is the hypothesis that you are testing. The null hypothesis states that there is no significant difference or relationship between the variables. It is important to write the null hypothesis because it allows you to compare your results with what would be expected by chance.

Refine the Hypothesis

After formulating the hypothesis, it’s important to refine it and make it more precise. This may involve clarifying the variables, specifying the direction of the relationship, or making the hypothesis more testable.

Examples of Hypothesis

Here are a few examples of hypotheses in different fields:

  • Psychology : “Increased exposure to violent video games leads to increased aggressive behavior in adolescents.”
  • Biology : “Higher levels of carbon dioxide in the atmosphere will lead to increased plant growth.”
  • Sociology : “Individuals who grow up in households with higher socioeconomic status will have higher levels of education and income as adults.”
  • Education : “Implementing a new teaching method will result in higher student achievement scores.”
  • Marketing : “Customers who receive a personalized email will be more likely to make a purchase than those who receive a generic email.”
  • Physics : “An increase in temperature will cause an increase in the volume of a gas, assuming all other variables remain constant.”
  • Medicine : “Consuming a diet high in saturated fats will increase the risk of developing heart disease.”

Purpose of Hypothesis

The purpose of a hypothesis is to provide a testable explanation for an observed phenomenon or a prediction of a future outcome based on existing knowledge or theories. A hypothesis is an essential part of the scientific method and helps to guide the research process by providing a clear focus for investigation. It enables scientists to design experiments or studies to gather evidence and data that can support or refute the proposed explanation or prediction.

The formulation of a hypothesis is based on existing knowledge, observations, and theories, and it should be specific, testable, and falsifiable. A specific hypothesis helps to define the research question, which is important in the research process as it guides the selection of an appropriate research design and methodology. Testability of the hypothesis means that it can be proven or disproven through empirical data collection and analysis. Falsifiability means that the hypothesis should be formulated in such a way that it can be proven wrong if it is incorrect.

In addition to guiding the research process, the testing of hypotheses can lead to new discoveries and advancements in scientific knowledge. When a hypothesis is supported by the data, it can be used to develop new theories or models to explain the observed phenomenon. When a hypothesis is not supported by the data, it can help to refine existing theories or prompt the development of new hypotheses to explain the phenomenon.

When to use Hypothesis

Here are some common situations in which hypotheses are used:

  • In scientific research , hypotheses are used to guide the design of experiments and to help researchers make predictions about the outcomes of those experiments.
  • In social science research , hypotheses are used to test theories about human behavior, social relationships, and other phenomena.
  • I n business , hypotheses can be used to guide decisions about marketing, product development, and other areas. For example, a hypothesis might be that a new product will sell well in a particular market, and this hypothesis can be tested through market research.

Characteristics of Hypothesis

Here are some common characteristics of a hypothesis:

  • Testable : A hypothesis must be able to be tested through observation or experimentation. This means that it must be possible to collect data that will either support or refute the hypothesis.
  • Falsifiable : A hypothesis must be able to be proven false if it is not supported by the data. If a hypothesis cannot be falsified, then it is not a scientific hypothesis.
  • Clear and concise : A hypothesis should be stated in a clear and concise manner so that it can be easily understood and tested.
  • Based on existing knowledge : A hypothesis should be based on existing knowledge and research in the field. It should not be based on personal beliefs or opinions.
  • Specific : A hypothesis should be specific in terms of the variables being tested and the predicted outcome. This will help to ensure that the research is focused and well-designed.
  • Tentative: A hypothesis is a tentative statement or assumption that requires further testing and evidence to be confirmed or refuted. It is not a final conclusion or assertion.
  • Relevant : A hypothesis should be relevant to the research question or problem being studied. It should address a gap in knowledge or provide a new perspective on the issue.

Advantages of Hypothesis

Hypotheses have several advantages in scientific research and experimentation:

  • Guides research: A hypothesis provides a clear and specific direction for research. It helps to focus the research question, select appropriate methods and variables, and interpret the results.
  • Predictive powe r: A hypothesis makes predictions about the outcome of research, which can be tested through experimentation. This allows researchers to evaluate the validity of the hypothesis and make new discoveries.
  • Facilitates communication: A hypothesis provides a common language and framework for scientists to communicate with one another about their research. This helps to facilitate the exchange of ideas and promotes collaboration.
  • Efficient use of resources: A hypothesis helps researchers to use their time, resources, and funding efficiently by directing them towards specific research questions and methods that are most likely to yield results.
  • Provides a basis for further research: A hypothesis that is supported by data provides a basis for further research and exploration. It can lead to new hypotheses, theories, and discoveries.
  • Increases objectivity: A hypothesis can help to increase objectivity in research by providing a clear and specific framework for testing and interpreting results. This can reduce bias and increase the reliability of research findings.

Limitations of Hypothesis

Some Limitations of the Hypothesis are as follows:

  • Limited to observable phenomena: Hypotheses are limited to observable phenomena and cannot account for unobservable or intangible factors. This means that some research questions may not be amenable to hypothesis testing.
  • May be inaccurate or incomplete: Hypotheses are based on existing knowledge and research, which may be incomplete or inaccurate. This can lead to flawed hypotheses and erroneous conclusions.
  • May be biased: Hypotheses may be biased by the researcher’s own beliefs, values, or assumptions. This can lead to selective interpretation of data and a lack of objectivity in research.
  • Cannot prove causation: A hypothesis can only show a correlation between variables, but it cannot prove causation. This requires further experimentation and analysis.
  • Limited to specific contexts: Hypotheses are limited to specific contexts and may not be generalizable to other situations or populations. This means that results may not be applicable in other contexts or may require further testing.
  • May be affected by chance : Hypotheses may be affected by chance or random variation, which can obscure or distort the true relationship between variables.

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what is an educated guess in science

Understanding What is an Educated Guess in Science

Table of Contents

An educated guess in science, commonly referred to as a hypothesis, is a prediction or statement that can be tested through experiments and observations. It is based on careful observations, thorough research, and existing knowledge about the subject. By formulating hypotheses, scientists aim to explore and understand the natural world around us.

The scientific method is a problem-solving procedure utilized by scientists to draw conclusions and uncover new insights. It involves several steps, including identifying the problem, gathering relevant information, formulating hypotheses, testing them through experiments, analyzing results, and drawing conclusions based on the evidence gathered.

Variables play a crucial role in scientific experiments. These are factors that can change and have an impact on the outcome. The independent variable is controlled and deliberately changed by the researcher, while the dependent variable changes based on the manipulation of the independent variable. Additionally, a control is used as a standard for comparison to ensure accurate results.

In the realm of scientific inquiry, there is a distinction between scientific theory and scientific law. A scientific theory is an explanation that is supported by results obtained from tests or experiments. On the other hand, a scientific law describes the behavior of a natural phenomenon or a set of phenomena. Both theories and laws contribute to our understanding of the natural world.

When conducting scientific research, it is crucial to consider ethics and be aware of potential biases that can influence the outcomes of experiments and observations. Adhering to ethical guidelines ensures the integrity and credibility of scientific investigations, and recognizing and minimizing biases helps maintain objectivity in the pursuit of knowledge.

The steps of the scientific method guide scientists in their quest for understanding. It begins with careful observation of the natural world, followed by the formulation of a hypothesis, making predictions based on the hypothesis, conducting controlled experiments, and finally drawing conclusions based on the results obtained.

An educated guess, or a hypothesis, is a fundamental building block of scientific inquiry. It guides the direction of research and experimentation, providing a framework for investigation and discovery. By formulating hypotheses, scientists can make informed predictions and explore the intricacies of the natural world.

Key Takeaways:

  • An educated guess, known as a hypothesis, is a testable prediction or statement in scientific research.
  • The scientific method is a problem-solving procedure that involves steps like identifying a problem, formulating hypotheses, conducting experiments, and drawing conclusions.
  • Variables in experiments can change and impact the outcome, with the independent variable being deliberately altered by the researcher.
  • Scientific theory and scientific law are different concepts, with theories explaining phenomena and laws describing behavior.
  • Ethics and minimizing bias are crucial aspects of scientific research.

The Scientific Method and Hypothesis

The scientific method is a problem-solving procedure employed by scientists to draw conclusions, which involves identifying a problem, gathering information, making hypotheses, testing them, analyzing results, and drawing conclusions. It is a rigorous approach that ensures the credibility and reliability of scientific investigations.

At the heart of the scientific method lies the hypothesis, an essential component of scientific inquiry. An educated guess, the hypothesis is a prediction or statement that can be tested. It is formulated based on observations, research, and existing knowledge about the subject under investigation. The hypothesis serves as a guide to design experiments and gather relevant data to support or refute it.

Scientific inference and logical deduction play crucial roles in generating hypotheses. Scientists use the available evidence and reasoning to make logical deductions and form educated guesses about how phenomena work. These hypotheses are then tested through rigorous experimentation and analysis, providing valuable insights into the workings of the natural world.

Scientific Method Steps
1. Observation
2. Hypothesis
3. Prediction
4. Experiment
5. Conclusion

By following the steps of the scientific method, scientists gain valuable knowledge and understanding of the natural world. The systematic approach allows researchers to gather evidence, form hypotheses, and test them in a controlled environment. Through rigorous experimentation and analysis, scientists draw conclusions that contribute to the advancement of scientific knowledge.

To learn more about the scientific method and its role in hypothesis formation, visit Exquisitive Education , where you can explore a range of educational resources on scientific inquiry and critical thinking.

Variables and Control in Experiments

Variables are factors that can be manipulated and measured in scientific experiments, with the independent variable intentionally changed by the researcher and the dependent variable responding to the changes. In a well-designed experiment, the independent variable is the factor that is deliberately manipulated or changed to observe its effects on the dependent variable, which is the factor that changes as a result of the manipulation.

In order to ensure the validity and reliability of the experiment, it is important to have a control group. A control group is a standard against which the experimental results can be compared. It is identical to the experimental group in every aspect, except that the independent variable is not manipulated. By comparing the results of the experimental group to the control group, scientists can determine the specific effects of the independent variable.

Types of Variables in Experiments:

There are three main types of variables in scientific experiments: independent variables, dependent variables, and controlled variables. The independent variable is the variable that is deliberately changed or manipulated by the researcher. It is the cause or input that is being tested. The dependent variable, on the other hand, is the variable that responds to the changes in the independent variable. It is the effect or outcome that is being measured or observed. Lastly, controlled variables are the factors that remain constant throughout the experiment to ensure that they do not influence the results. These variables are kept the same for both the experimental and control groups.

Variable TypeDescription
Independent VariableThe variable that is deliberately changed or manipulated by the researcher.
Dependent VariableThe variable that responds to the changes in the independent variable. It is the outcome being measured or observed.
Controlled VariablesThe factors that remain constant throughout the experiment to ensure that they do not influence the results.

Understanding and controlling variables in experiments is crucial for conducting reliable and valid scientific research. By carefully manipulating and measuring variables, scientists can investigate cause-and-effect relationships and draw meaningful conclusions about the natural world.

The Role of Scientific Theory and Law

In the realm of science, a scientific theory is an explanation that is supported by consistent results obtained through experimentation or observation, whereas a scientific law describes the observed behavior of a natural phenomenon. Scientists use theories and laws to understand and explain the workings of the natural world.

A scientific theory is a comprehensive explanation that has been extensively tested and has withstood the scrutiny of repeated experiments. It provides a framework for understanding complex phenomena and allows scientists to make predictions and further investigate the subject. Theories are built upon existing knowledge and are constantly refined as new evidence emerges.

On the other hand, scientific laws are concise statements that describe a fundamental principle or relationship in nature. Laws are derived from empirical observations and are universally applicable within a specific set of conditions. Unlike theories, laws do not attempt to explain the underlying mechanisms or reasons behind a natural phenomenon, but rather serve as concise descriptions of what happens.

The Difference Between Theories and Laws

To better understand the distinction between scientific theories and laws, consider the example of gravity. Isaac Newton’s law of universal gravitation describes the force of attraction between two objects due to their mass and distance. It provides a mathematical formula to calculate the force but does not explain why gravity exists or how it works.

Albert Einstein’s theory of general relativity, on the other hand, provides a deeper understanding of gravity by describing it as the curvature of spacetime caused by the presence of mass and energy. It explains the observed phenomena such as the curvature of light around massive objects and the expansion of the universe.

In summary, scientific theories and laws are both essential in the field of science. Theories provide comprehensive explanations supported by empirical evidence, while laws describe fundamental principles or relationships in nature. Together, they form the foundation of scientific knowledge and guide further exploration and understanding of the natural world.

The Role of Scientific Theory and Law
Scientific theoryExplanation supported by consistent resultsFramework for understanding complex phenomenaSubject to refinement with new evidence
Scientific lawConcise statement describing observed behaviorDerived from empirical observationsUniversally applicable within specific conditions

Ethics and Bias in Scientific Research

Ethical considerations are paramount in scientific research to ensure the welfare of subjects and the integrity of the scientific process, while bias can introduce unintended influences and affect the objectivity of results. In order to conduct ethical research, scientists must adhere to strict guidelines and principles that prioritize the safety and well-being of participants. This includes obtaining informed consent, maintaining privacy and confidentiality, and minimizing any potential harm or discomfort. By upholding ethical standards, researchers can ensure that their findings are reliable and trustworthy.

Bias, on the other hand, can pose a significant challenge to the accuracy and validity of scientific research. Bias refers to the preconceived notions or preferences that researchers may have, consciously or unconsciously, which can influence the design, execution, and interpretation of their studies. Common types of bias include confirmation bias, where researchers seek evidence that supports their preconceived ideas, and selection bias, where certain groups or individuals are favored over others in the study sample. To mitigate bias, scientists employ rigorous study designs, control groups, and blind or double-blind experimental methods to minimize subjective influence and ensure objective analysis of results.

It is crucial for scientists to acknowledge and address bias in order to uphold the credibility of their research. This involves transparently reporting any potential conflicts of interest, actively seeking diverse perspectives, and conducting peer review to ensure independent scrutiny of the study. Additionally, rigorous statistical analysis can help identify any potential biases and provide a more accurate assessment of the data. By actively working to minimize bias, researchers can maintain the integrity and validity of their findings, contributing to the overall advancement of scientific knowledge.

Type of BiasDescription
Confirmation BiasThe tendency to favor information that confirms existing beliefs or hypotheses, while disregarding conflicting evidence.
Selection BiasThe bias introduced when the participants or data selected for the study are not representative of the entire population, leading to inaccurate conclusions.
Publication BiasThe bias that can occur when the results of studies with statistically significant findings are more likely to be published, leading to an overrepresentation of positive results in scientific literature.

Importance of Addressing Bias

Addressing bias in scientific research is essential for maintaining the integrity and reliability of the findings. By mitigating bias, scientists can ensure that their research is objective, transparent, and unbiased. This allows for more accurate conclusions and fosters trust among the scientific community and the general public. Additionally, identifying and addressing biases can lead to the discovery of new insights and perspectives, as researchers actively seek out diverse viewpoints and challenge their own assumptions. Ultimately, by striving to minimize bias, scientists can contribute to the collective knowledge and understanding of the natural world.

Steps of the Scientific Method

The scientific method follows a structured process that includes observation, hypothesis formation, making predictions based on the hypothesis, conducting experiments to test the predictions, and drawing conclusions based on the results. It is a systematic approach used by scientists to investigate and understand the natural world.

1. Observation: The first step is to carefully observe and gather information about a particular phenomenon or problem. This involves using our senses or using instruments to collect data.

2. Hypothesis: Based on the observations, a hypothesis is formulated. A hypothesis is an educated guess or prediction that can be tested through experiments. It is a proposed explanation for the observed phenomenon.

3. Prediction: Once a hypothesis is formulated, predictions are made. These predictions are statements that suggest specific outcomes or patterns that should be observed if the hypothesis is correct.

4. Experiment: Experiments are conducted to test the predictions made by the hypothesis. Controlled experiments are designed with specific variables in mind. The independent variable, which is deliberately changed by the researcher, is manipulated, while the dependent variable, which changes as a result, is measured and observed.

5. Conclusion: After conducting the experiment and analyzing the results, conclusions are drawn. The data collected is evaluated to determine whether the predictions made by the hypothesis are supported or refuted. If the results support the predictions, the hypothesis is considered valid. If the results do not support the predictions, the hypothesis may need to be revised or discarded.

By following these steps, scientists can systematically investigate and understand various phenomena in the natural world. The scientific method allows for rigorous testing and analysis, ensuring that scientific knowledge is based on reliable evidence and logical reasoning.

StepDescription
ObservationGathering information about a phenomenon or problem
HypothesisFormulating an educated guess or prediction
PredictionMaking specific statements about expected outcomes
ExperimentConducting controlled experiments to test predictions
ConclusionAnalyzing results and drawing conclusions

Learn more about the scientific method and its application in various scientific disciplines at Exquisitive Education .

Definition and Importance of an Educated Guess

An educated guess, also known as a hypothesis in the scientific community, plays a crucial role in scientific investigations as it provides a starting point for experimentation and serves as a guide for further exploration. A hypothesis is a prediction or statement that can be tested, formulated based on observations, research, and existing knowledge about the subject. It acts as a tentative explanation for a scientific phenomenon or problem, allowing scientists to make predictions and design experiments to gather empirical evidence.

Scientists use the scientific method, a problem-solving procedure, to systematically investigate natural phenomena. This method involves identifying a problem, gathering relevant information, formulating hypotheses, testing them through controlled experiments, analyzing the results, and drawing conclusions. The hypothesis stage is key, as it provides a framework for experimentation and helps researchers narrow down their focus.

Variables are factors that can change in an experiment. The independent variable is deliberately changed by the researcher, while the dependent variable is observed and changes as a result. By manipulating the independent variable and measuring changes in the dependent variable, scientists can establish cause-and-effect relationships. It is also essential to have a control, which serves as a standard for comparison. This control allows researchers to isolate the effects of the independent variable, ensuring that any observed changes can be attributed to the variable being tested.

Table: Examples of Variables in Scientific Experiments

ExperimentIndependent VariableDependent Variable
Effect of sunlight on plant growthAmount of sunlight receivedHeight or growth rate of plants
Impact of temperature on enzyme activityTemperatureRate of enzyme activity
Effect of exercise on heart rateDuration and intensity of exerciseHeart rate

In the scientific community, theories and laws play different roles in explaining natural phenomena. A scientific theory is an explanation supported by results obtained from tests or experiments. It incorporates a broad range of evidence to explain a wide range of related observations. On the other hand, a scientific law is a description of the behavior of something in nature, typically expressed in a mathematical formula. Laws are concise descriptions of observations that have been repeatedly verified through experimentation.

Ethics and bias are important considerations in scientific research. Scientists must adhere to ethical guidelines to ensure the well-being of subjects, the integrity of data, and the overall trustworthiness of their work. Bias, whether conscious or unconscious, can influence the outcomes of experiments and observations, potentially undermining the objectivity of scientific research. Therefore, scientists should strive to minimize bias and ensure that their findings are based on rigorous and unbiased analysis.

In summary, an educated guess, or hypothesis, forms the foundation of scientific investigations. It enables scientists to formulate predictions and design experiments to gather empirical evidence. By systematically following the scientific method, scientists can explore natural phenomena, establish cause-and-effect relationships, and contribute to our understanding of the world around us.

Exploring Inference and Estimation in Science

Inference and estimation are essential tools in scientific inquiry, allowing scientists to draw conclusions and approximate values based on their observations and data. These processes play a crucial role in understanding and explaining the natural world. Through inference, scientists can make logical deductions based on available evidence to formulate educated guesses or hypotheses. This enables them to develop theories that explain phenomena and guide further investigations.

Estimation, on the other hand, involves approximating values or quantities when precise measurements may be challenging or impossible to obtain. Scientists often use estimation to make predictions or projections about future outcomes based on existing data. By employing mathematical models and statistical techniques, they can extrapolate trends, interpolate missing information, and make reasoned judgments about the behavior of natural phenomena.

In scientific experiments, inference and estimation are particularly important in the analysis of results. By interpreting data through statistical methods, scientists can determine the significance of their findings and draw meaningful conclusions. These processes also help researchers identify potential sources of error or bias and refine their methodologies for future investigations. Inference and estimation contribute to the continual advancement of scientific knowledge, allowing scientists to refine their understanding of the natural world and improve predictions and projections for various scientific disciplines.

Benefits of Inference and Estimation in Science
1. Enables logical deductions based on available evidence
2. Supports the formulation of educated guesses and hypotheses
3. Facilitates the development of scientific theories
4. Provides approximations when precise measurements are challenging
5. Helps make predictions and projections based on existing data
6. Contributes to the analysis and interpretation of experimental results

In summary, inference and estimation are vital tools that scientists use to draw conclusions, develop theories, and approximate values in scientific inquiry. Through these processes, researchers can navigate the complexities of the natural world and expand our understanding of it. From formulating educated guesses to analyzing experimental data, inference and estimation play a foundational role in advancing scientific knowledge.

Predicting and Projecting Future Outcomes

Prediction and projection are valuable aspects of scientific inquiry, as they enable scientists to anticipate and envision future outcomes based on existing knowledge and data. By analyzing patterns and trends, scientists can make informed judgments about what may occur in the future within various scientific disciplines. These predictions and projections serve as a stepping stone towards further exploration and discovery, guiding researchers towards new avenues of investigation.

When predicting future outcomes, scientists draw upon a vast array of information gathered through research, experiments, and observations. This data acts as a foundation for understanding the behavior of natural phenomena and allows scientists to establish correlations and patterns. Through careful analysis, scientists can make reasonable predictions about how these phenomena may behave in the future, providing valuable insights into the potential consequences of certain actions or events.

Projection, on the other hand, involves taking existing data and applying it to future scenarios. By extrapolating from historical trends and patterns, scientists can project how certain variables may change and impact the natural world. These projections can assist in decision-making processes and help society plan for and mitigate potential risks or challenges.

Utilizing Predictions and Projections

Predictions and projections form a vital part of scientific research and exploration. By utilizing these methods, scientists can hypothesize and test different scenarios, contributing to our understanding of the world and enabling us to make more informed choices in various fields. From climate change and environmental conservation to healthcare advancements and technological innovations, predictions and projections play a crucial role in shaping the future.

FieldPredictionsProjections
Climate SciencePredicting the impact of greenhouse gas emissions on global temperaturesProjecting sea-level rise based on melting ice caps
MedicinePredicting the spread of infectious diseases based on population densityProjecting the effectiveness of vaccines in preventing future outbreaks
TechnologyPredicting advancements in artificial intelligence based on current trendsProjecting the development of renewable energy technologies

As we continue to explore the unknown and push the boundaries of scientific knowledge, predictions and projections will remain invaluable tools in guiding our understanding and shaping the world we live in. Through careful analysis, experimentation, and the utilization of existing data, scientists can uncover new insights and help shape a brighter future for all.

Preliminary Assessment and Rough Calculation

Preliminary assessments and rough calculations serve as initial steps in scientific investigations, providing scientists with a basis for further analysis and decision-making. These processes allow researchers to make informed judgments and estimations before delving into more complex experiments or analyses.

When conducting a preliminary assessment, scientists gather relevant data and information to gain a general understanding of the subject matter. This involves reviewing existing studies, conducting literature reviews, and examining previous research findings. By doing so, scientists can identify any knowledge gaps or areas that require further investigation.

Once the preliminary assessment is complete, scientists move on to rough calculations. These calculations are often used to make estimations or approximations of key variables or outcomes. They involve applying reasoned judgment, extrapolation, and interpolation to arrive at rough values or ranges. While the accuracy of these calculations may be limited, they provide a starting point for more rigorous analysis and experimentation.

Overall, preliminary assessments and rough calculations are essential tools in the scientific process. They allow scientists to develop an initial understanding of a phenomenon or problem, guiding them towards more focused research and experimentation. By utilizing these early steps effectively, researchers can lay the foundation for meaningful scientific discoveries and advancements.

Type of AssessmentKey Characteristics
Preliminary AssessmentGathering existing data and information, identifying knowledge gaps
Rough CalculationEstimations and approximations using reasoned judgment, extrapolation, and interpolation

Exploring the Role of Hypothesis in Science

Hypotheses, often referred to as educated guesses, are integral to scientific research, guiding the design of experiments and providing a framework for investigating specific questions or phenomena. These hypotheses are based on observations, research, and existing knowledge about the subject at hand. By formulating a hypothesis, scientists can make predictions and test their ideas in a systematic and objective manner.

One of the fundamental aspects of scientific inquiry is the use of the scientific method. This problem-solving procedure allows scientists to gather information, make hypotheses, test them through experimentation, analyze the results, and draw conclusions. The hypothesis serves as the initial prediction or statement that is tested in an experiment, helping scientists to focus their efforts and determine the direction of their research.

In scientific experiments, variables play a crucial role. Variables are factors that can change during the course of an experiment, and they can have a direct impact on the outcome. The independent variable is deliberately changed by the researcher, while the dependent variable is the one that changes as a result. Having a control, which is a standard to compare results to, ensures that any changes observed can be attributed to the independent variable and not other factors.

Key Points:
An educated guess in science is called a hypothesis.
The scientific method is a problem-solving procedure used by scientists to draw conclusions.
Variables are factors that can change in an experiment, with the independent variable deliberately changed by the researcher.
A control is a standard used for comparison in scientific experiments.

In addition to the role of hypotheses and variables, the distinction between scientific theory and scientific law is also significant. A scientific theory is an explanation that is supported by results obtained from tests or experiments, while a scientific law describes the behavior of something in nature. These concepts help to shape our understanding of the natural world and provide frameworks for further scientific exploration.

It’s important to note that ethics and bias can influence scientific research. Scientists are guided by ethical considerations to ensure the welfare of subjects, accurate reporting, and responsible conduct. Additionally, biases, both conscious and unconscious, can influence the outcomes of experiments and observations. Recognizing and addressing these factors is essential for maintaining the integrity of scientific research.

In conclusion, hypotheses, or educated guesses, play a vital role in scientific research. They guide the design of experiments, allow scientists to make predictions, and provide a framework for investigating specific questions or phenomena. By understanding the role of hypotheses in the scientific method and recognizing the impact of variables, theories, laws, ethics, and bias, we can gain a deeper appreciation for the process of scientific inquiry and its contributions to our understanding of the natural world.

Useful Resources:
To learn more about scientific research and hypothesis formulation, visit .

In conclusion, understanding what an educated guess is in science, commonly known as a hypothesis, is crucial for comprehending and advancing our scientific knowledge. An educated guess, or hypothesis, is a prediction or statement that can be tested through observation, research, and existing knowledge. It serves as a starting point for scientific exploration, guiding the formulation of experiments and driving the course of scientific inquiry.

The scientific method, a problem-solving procedure employed by scientists, relies heavily on hypotheses. It involves identifying a problem, gathering information, making hypotheses, testing them through experiments, analyzing the results, and drawing conclusions. By adhering to this structured approach, scientists can validate or refine their educated guesses, ultimately contributing to the accumulation of scientific knowledge.

Variables, such as the independent and dependent variables, play a crucial role in scientific experiments. The independent variable, purposely manipulated by researchers, causes changes in the dependent variable. Additionally, having a control group enables scientists to compare results and determine the impact of the independent variable. This controlled experimentation allows for reliable conclusions to be drawn from the data.

Ethics and bias also exert influence throughout the scientific research process. Maintaining ethical standards is essential to protect the well-being of subjects and ensure the integrity of the results. Meanwhile, acknowledging and addressing bias helps to eliminate any distortions that may skew the outcomes of experiments and observations.

In summary, understanding the concept of an educated guess, or hypothesis, is fundamental in scientific inquiry. By utilizing the scientific method, considering variables, acknowledging ethical considerations, and mitigating bias, scientists can make substantial contributions to our understanding of the natural world. Continued exploration and investigation, guided by educated guesses, pave the way for new discoveries and advancements in various scientific disciplines.

Q: What is an educated guess in science?

A: An educated guess in science, also known as a hypothesis, is a prediction or statement that can be tested. It is based on observations, research, and existing knowledge about the subject.

Q: What is the scientific method?

A: The scientific method is a problem-solving procedure used by scientists to draw conclusions. It involves identifying a problem, gathering information, making hypotheses, testing them, analyzing results, and drawing conclusions.

Q: What are variables in experiments?

A: Variables are factors that can change in an experiment. The independent variable is deliberately changed by the researcher, while the dependent variable changes as a result.

Q: What is a control in an experiment?

A: A control is a standard used to compare the results of an experiment to. It helps scientists assess the impact of the independent variable on the dependent variable.

Q: What is the difference between a scientific theory and a scientific law?

A: A scientific theory is an explanation backed by results obtained from tests or experiments. A scientific law describes the behavior of something in nature.

Q: How do ethics and bias play a role in scientific research?

A: Ethics play a role in scientific research by ensuring that experiments are conducted responsibly and with respect for human and animal subjects. Bias can influence the outcomes of experiments and observations, which is why it is crucial for scientists to strive for objectivity.

Q: What are the steps of the scientific method?

A: The steps of the scientific method are observation, hypothesis formation, making predictions, conducting experiments, and drawing conclusions.

Q: Why is an educated guess important in science?

A: An educated guess, or hypothesis, is important in science as it guides the formulation of experiments and drives scientific investigations. It allows scientists to make predictions and test their understanding of the natural world.

About The Author

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Ethan Emerson is a passionate author and dedicated advocate for the transformative power of education. With a background in teaching and a love for writing, Ethan brings a unique blend of expertise and creativity to his contributions on ExquisitiveEducation.com .His articles are a delightful mix of insightful knowledge and engaging storytelling, aiming to inspire and empower learners of all ages. Ethan's mission is to ignite the spark of curiosity and foster a love for learning in every reader.Ethan Emerson, is your companion in the realm of general education exploration. With a passion for knowledge, He delves into the intricate world of Education Expenses & Discounts , uncovering financial insights for your educational journey. From the vitality of Physical Education to the synergy of Education & Technology , Ethan's here to bridge the gap between traditional and innovative learning methods. Discover the art of crafting impressive Resume & Personal Documentation in Education , as well as insights into diverse Career Paths, Degrees & Educational Requirements . Join Ethan in navigating through a sea of Educational Courses & Classes , exploring the nuances of various Education Systems , and understanding the empowering realm of Special Education . With an eye on Teaching & Teachers , He offers a glimpse into the world of educators who shape minds. Let's unlock Studying Tips & Learning Methods that turn education into a delightful journey of growth with Exquisitive Education .

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scientific hypothesis , an idea that proposes a tentative explanation about a phenomenon or a narrow set of phenomena observed in the natural world. The two primary features of a scientific hypothesis are falsifiability and testability, which are reflected in an “If…then” statement summarizing the idea and in the ability to be supported or refuted through observation and experimentation. The notion of the scientific hypothesis as both falsifiable and testable was advanced in the mid-20th century by Austrian-born British philosopher Karl Popper .

The formulation and testing of a hypothesis is part of the scientific method , the approach scientists use when attempting to understand and test ideas about natural phenomena. The generation of a hypothesis frequently is described as a creative process and is based on existing scientific knowledge, intuition , or experience. Therefore, although scientific hypotheses commonly are described as educated guesses, they actually are more informed than a guess. In addition, scientists generally strive to develop simple hypotheses, since these are easier to test relative to hypotheses that involve many different variables and potential outcomes. Such complex hypotheses may be developed as scientific models ( see scientific modeling ).

Depending on the results of scientific evaluation, a hypothesis typically is either rejected as false or accepted as true. However, because a hypothesis inherently is falsifiable, even hypotheses supported by scientific evidence and accepted as true are susceptible to rejection later, when new evidence has become available. In some instances, rather than rejecting a hypothesis because it has been falsified by new evidence, scientists simply adapt the existing idea to accommodate the new information. In this sense a hypothesis is never incorrect but only incomplete.

The investigation of scientific hypotheses is an important component in the development of scientific theory . Hence, hypotheses differ fundamentally from theories; whereas the former is a specific tentative explanation and serves as the main tool by which scientists gather data, the latter is a broad general explanation that incorporates data from many different scientific investigations undertaken to explore hypotheses.

Countless hypotheses have been developed and tested throughout the history of science . Several examples include the idea that living organisms develop from nonliving matter, which formed the basis of spontaneous generation , a hypothesis that ultimately was disproved (first in 1668, with the experiments of Italian physician Francesco Redi , and later in 1859, with the experiments of French chemist and microbiologist Louis Pasteur ); the concept proposed in the late 19th century that microorganisms cause certain diseases (now known as germ theory ); and the notion that oceanic crust forms along submarine mountain zones and spreads laterally away from them ( seafloor spreading hypothesis ).

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Scientific Method: Step 3: HYPOTHESIS

  • Step 1: QUESTION
  • Step 2: RESEARCH
  • Step 3: HYPOTHESIS
  • Step 4: EXPERIMENT
  • Step 5: DATA
  • Step 6: CONCLUSION

Step 3: State your hypothesis

Now it's time to state your hypothesis . The hypothesis is an educated guess as to what will happen during your experiment. 

The hypothesis is often written using the words "IF" and "THEN." For example, " If I do not study, then I will fail the test." The "if' and "then" statements reflect your independent and dependent variables . 

The hypothesis should relate back to your original question and must be testable .

A word about variables...

Your experiment will include variables to measure and to explain any cause and effect. Below you will find some useful links describing the different types of variables.

  • "What are independent and dependent variables" NCES
  • [VIDEO] Biology: Independent vs. Dependent Variables (Nucleus Medical Media) Video explaining independent and dependent variables, with examples.

Resource Links

  • What is and How to Write a Good Hypothesis in Research? (Elsevier)
  • Hypothesis brochure from Penn State/Berks

  • << Previous: Step 2: RESEARCH
  • Next: Step 4: EXPERIMENT >>
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Facts, Hypotheses, Theories, and Laws: What’s the Difference?

Perhaps no topic in science garners more confusion among the general public than the distinction between a theory and a hypothesis. This confusion is highly regrettable, because the distinction is one of the most fundamental concepts in science, and a lack of understanding about these definitions leads to a great deal of confusion. Therefore, I will attempt to alleviate the maelstrom of nonsense and bewilderment surrounding these terms and endow my readers with a proper understanding of their meanings.

Let’s begin with the definition of “fact.” This is actually the hardest of these terms to define. Basically, it’s just something that has been observed and tested and shown to be true. Importantly, facts generally don’t offer explanations, they are just how things are. If we want an explanation of why things are the way that they are, we have to turn to hypotheses and theories.

This is where most people mess up. In the common vernacular, a theory is “an educated guess,” but in science, an educated guess is a hypothesis, not a theory. Further, when I ask my students to define a theory, I often get answers like, “something that we think is true, but haven’t tested,” or even worse, “an idea that can’t be tested.” Television further reinforces these misconceptions, by constantly misusing “theory.” In virtually every episode of shows like “House M.D.” and “Bones” someone says, “my theory is that…” The reality is that in science, a theory is much, much more than just an educated guess. In fact, theories are the highest form of scientific certainty. They have been rigorously test over and over again and they have been shown to have a very high predictive power. In other words, they consistently and accurately predict the outcomes of experiments.

For example, suppose that I am currently holding a pen in the air. What will happen if I release my hand? Hopefully, you all thought, “the pen will drop,” but why did you make that prediction? In fact, you were simply applying the theory of universal gravity. This is the theory that all bodies produce gravity and are acted upon by the gravity of other bodies. Also note that by dropping the pen, I would demonstrate the fact of gravity. In other words, it is a fact that gravity took hold of the pen and caused it to fall. To explain that fact, we apply the theory of universal gravity which tells us that the earth produces a field of gravity which attracted the pen (in reality of course the theory also tells us the exact rate of acceleration of the pen). So you see, we use theories to explain facts. As such, they actually supersede facts in their certainty and importance.

So if a theory is an explanatory framework with a high predictive power, what then is a hypothesis? A hypothesis is basically an educated guess. It’s a possible explanation that hasn’t yet achieved the certainty of a theory. There may be experimental support behind it, but not on the level that a theory has. It is, however, entirely possible for a hypothesis to become a theory once enough evidence has been accumulated.

At this point, you all are probably wondering what a law is, because my explanation of a theory probably sounds a lot like what you expected for the definition of a law, and there is a very good reason for that. Namely, the terms “theory” and “law” are essentially synonymous. “Law” is an older term that we don’t use as much anymore, but it has the same level of certainty as a theory. For example, the law of universal gravity and the theory of universal gravity are synonyms. They mean the exact same thing and either one is equally correct.

So why does this matter? Other than scientists, who really cares if people say “theory” when they mean “hypothesis?” The reality is that this confusion leads to a great many misunderstandings and faulty arguments. The most prominent example is the argument that, “evolution shouldn’t be being taught as a fact because it’s just a theory.” As we’ve just seen, theories are actually our highest form of scientific certainty, and they actually supersede facts because they explain the facts. So saying, “evolution is just a theory” is no different from saying, “gravity is just a law.” Theories make up the cornerstones of every branch of science. For example, the germ theory of disease states that viruses, bacteria, etc. make us sick, cell theory states that all living things are made of cells, atomic theory states that all matter is made of atoms, etc. Obviously, there aren’t any outcries about people teaching the notion that matter is made of elements as a fact, even though its “just a theory.” Further, all theories contain a factual component because they explain the facts (I illustrated this previously with my gravity example). So, when it comes to evolution, the idea that life on this planet has slowly changed over millions of years is considered scientific fact. We have ample evidence for it from fossils, genetics, etc. The theory is the “theory of evolution by natural selection” which states that natural selection has been the primary driver of evolution. So the core thing that most creationists oppose (i.e., the idea that life has evolved) is not a theory, it is a fact. The theory of natural selection simply explains what caused those changes to take place.

In summary, a fact is a tested and confirmed observation or measurement. A hypothesis is basically an educated guess, and the terms theory and law synonymously describe a thoroughly tested explanatory framework which has a high predictive power and explains facts.

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Scientific Hypothesis Examples

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  • Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
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A hypothesis is an educated guess about what you think will happen in a scientific experiment, based on your observations. Before conducting the experiment, you propose a hypothesis so that you can determine if your prediction is supported.

There are several ways you can state a hypothesis, but the best hypotheses are ones you can test and easily refute. Why would you want to disprove or discard your own hypothesis? Well, it is the easiest way to demonstrate that two factors are related. Here are some good scientific hypothesis examples:

  • Hypothesis: All forks have three tines. This would be disproven if you find any fork with a different number of tines.
  • Hypothesis: There is no relationship between smoking and lung cancer. While it is difficult to establish cause and effect in health issues, you can apply statistics to data to discredit or support this hypothesis.
  • Hypothesis: Plants require liquid water to survive. This would be disproven if you find a plant that doesn't need it.
  • Hypothesis: Cats do not show a paw preference (equivalent to being right- or left-handed). You could gather data around the number of times cats bat at a toy with either paw and analyze the data to determine whether cats, on the whole, favor one paw over the other. Be careful here, because individual cats, like people, might (or might not) express a preference. A large sample size would be helpful.
  • Hypothesis: If plants are watered with a 10% detergent solution, their growth will be negatively affected. Some people prefer to state a hypothesis in an "If, then" format. An alternate hypothesis might be: Plant growth will be unaffected by water with a 10% detergent solution.
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The Craft of Writing a Strong Hypothesis

Deeptanshu D

Table of Contents

Writing a hypothesis is one of the essential elements of a scientific research paper. It needs to be to the point, clearly communicating what your research is trying to accomplish. A blurry, drawn-out, or complexly-structured hypothesis can confuse your readers. Or worse, the editor and peer reviewers.

A captivating hypothesis is not too intricate. This blog will take you through the process so that, by the end of it, you have a better idea of how to convey your research paper's intent in just one sentence.

What is a Hypothesis?

The first step in your scientific endeavor, a hypothesis, is a strong, concise statement that forms the basis of your research. It is not the same as a thesis statement , which is a brief summary of your research paper .

The sole purpose of a hypothesis is to predict your paper's findings, data, and conclusion. It comes from a place of curiosity and intuition . When you write a hypothesis, you're essentially making an educated guess based on scientific prejudices and evidence, which is further proven or disproven through the scientific method.

The reason for undertaking research is to observe a specific phenomenon. A hypothesis, therefore, lays out what the said phenomenon is. And it does so through two variables, an independent and dependent variable.

The independent variable is the cause behind the observation, while the dependent variable is the effect of the cause. A good example of this is “mixing red and blue forms purple.” In this hypothesis, mixing red and blue is the independent variable as you're combining the two colors at your own will. The formation of purple is the dependent variable as, in this case, it is conditional to the independent variable.

Different Types of Hypotheses‌

Types-of-hypotheses

Types of hypotheses

Some would stand by the notion that there are only two types of hypotheses: a Null hypothesis and an Alternative hypothesis. While that may have some truth to it, it would be better to fully distinguish the most common forms as these terms come up so often, which might leave you out of context.

Apart from Null and Alternative, there are Complex, Simple, Directional, Non-Directional, Statistical, and Associative and casual hypotheses. They don't necessarily have to be exclusive, as one hypothesis can tick many boxes, but knowing the distinctions between them will make it easier for you to construct your own.

1. Null hypothesis

A null hypothesis proposes no relationship between two variables. Denoted by H 0 , it is a negative statement like “Attending physiotherapy sessions does not affect athletes' on-field performance.” Here, the author claims physiotherapy sessions have no effect on on-field performances. Even if there is, it's only a coincidence.

2. Alternative hypothesis

Considered to be the opposite of a null hypothesis, an alternative hypothesis is donated as H1 or Ha. It explicitly states that the dependent variable affects the independent variable. A good  alternative hypothesis example is “Attending physiotherapy sessions improves athletes' on-field performance.” or “Water evaporates at 100 °C. ” The alternative hypothesis further branches into directional and non-directional.

  • Directional hypothesis: A hypothesis that states the result would be either positive or negative is called directional hypothesis. It accompanies H1 with either the ‘<' or ‘>' sign.
  • Non-directional hypothesis: A non-directional hypothesis only claims an effect on the dependent variable. It does not clarify whether the result would be positive or negative. The sign for a non-directional hypothesis is ‘≠.'

3. Simple hypothesis

A simple hypothesis is a statement made to reflect the relation between exactly two variables. One independent and one dependent. Consider the example, “Smoking is a prominent cause of lung cancer." The dependent variable, lung cancer, is dependent on the independent variable, smoking.

4. Complex hypothesis

In contrast to a simple hypothesis, a complex hypothesis implies the relationship between multiple independent and dependent variables. For instance, “Individuals who eat more fruits tend to have higher immunity, lesser cholesterol, and high metabolism.” The independent variable is eating more fruits, while the dependent variables are higher immunity, lesser cholesterol, and high metabolism.

5. Associative and casual hypothesis

Associative and casual hypotheses don't exhibit how many variables there will be. They define the relationship between the variables. In an associative hypothesis, changing any one variable, dependent or independent, affects others. In a casual hypothesis, the independent variable directly affects the dependent.

6. Empirical hypothesis

Also referred to as the working hypothesis, an empirical hypothesis claims a theory's validation via experiments and observation. This way, the statement appears justifiable and different from a wild guess.

Say, the hypothesis is “Women who take iron tablets face a lesser risk of anemia than those who take vitamin B12.” This is an example of an empirical hypothesis where the researcher  the statement after assessing a group of women who take iron tablets and charting the findings.

7. Statistical hypothesis

The point of a statistical hypothesis is to test an already existing hypothesis by studying a population sample. Hypothesis like “44% of the Indian population belong in the age group of 22-27.” leverage evidence to prove or disprove a particular statement.

Characteristics of a Good Hypothesis

Writing a hypothesis is essential as it can make or break your research for you. That includes your chances of getting published in a journal. So when you're designing one, keep an eye out for these pointers:

  • A research hypothesis has to be simple yet clear to look justifiable enough.
  • It has to be testable — your research would be rendered pointless if too far-fetched into reality or limited by technology.
  • It has to be precise about the results —what you are trying to do and achieve through it should come out in your hypothesis.
  • A research hypothesis should be self-explanatory, leaving no doubt in the reader's mind.
  • If you are developing a relational hypothesis, you need to include the variables and establish an appropriate relationship among them.
  • A hypothesis must keep and reflect the scope for further investigations and experiments.

Separating a Hypothesis from a Prediction

Outside of academia, hypothesis and prediction are often used interchangeably. In research writing, this is not only confusing but also incorrect. And although a hypothesis and prediction are guesses at their core, there are many differences between them.

A hypothesis is an educated guess or even a testable prediction validated through research. It aims to analyze the gathered evidence and facts to define a relationship between variables and put forth a logical explanation behind the nature of events.

Predictions are assumptions or expected outcomes made without any backing evidence. They are more fictionally inclined regardless of where they originate from.

For this reason, a hypothesis holds much more weight than a prediction. It sticks to the scientific method rather than pure guesswork. "Planets revolve around the Sun." is an example of a hypothesis as it is previous knowledge and observed trends. Additionally, we can test it through the scientific method.

Whereas "COVID-19 will be eradicated by 2030." is a prediction. Even though it results from past trends, we can't prove or disprove it. So, the only way this gets validated is to wait and watch if COVID-19 cases end by 2030.

Finally, How to Write a Hypothesis

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Quick tips on writing a hypothesis

1.  Be clear about your research question

A hypothesis should instantly address the research question or the problem statement. To do so, you need to ask a question. Understand the constraints of your undertaken research topic and then formulate a simple and topic-centric problem. Only after that can you develop a hypothesis and further test for evidence.

2. Carry out a recce

Once you have your research's foundation laid out, it would be best to conduct preliminary research. Go through previous theories, academic papers, data, and experiments before you start curating your research hypothesis. It will give you an idea of your hypothesis's viability or originality.

Making use of references from relevant research papers helps draft a good research hypothesis. SciSpace Discover offers a repository of over 270 million research papers to browse through and gain a deeper understanding of related studies on a particular topic. Additionally, you can use SciSpace Copilot , your AI research assistant, for reading any lengthy research paper and getting a more summarized context of it. A hypothesis can be formed after evaluating many such summarized research papers. Copilot also offers explanations for theories and equations, explains paper in simplified version, allows you to highlight any text in the paper or clip math equations and tables and provides a deeper, clear understanding of what is being said. This can improve the hypothesis by helping you identify potential research gaps.

3. Create a 3-dimensional hypothesis

Variables are an essential part of any reasonable hypothesis. So, identify your independent and dependent variable(s) and form a correlation between them. The ideal way to do this is to write the hypothetical assumption in the ‘if-then' form. If you use this form, make sure that you state the predefined relationship between the variables.

In another way, you can choose to present your hypothesis as a comparison between two variables. Here, you must specify the difference you expect to observe in the results.

4. Write the first draft

Now that everything is in place, it's time to write your hypothesis. For starters, create the first draft. In this version, write what you expect to find from your research.

Clearly separate your independent and dependent variables and the link between them. Don't fixate on syntax at this stage. The goal is to ensure your hypothesis addresses the issue.

5. Proof your hypothesis

After preparing the first draft of your hypothesis, you need to inspect it thoroughly. It should tick all the boxes, like being concise, straightforward, relevant, and accurate. Your final hypothesis has to be well-structured as well.

Research projects are an exciting and crucial part of being a scholar. And once you have your research question, you need a great hypothesis to begin conducting research. Thus, knowing how to write a hypothesis is very important.

Now that you have a firmer grasp on what a good hypothesis constitutes, the different kinds there are, and what process to follow, you will find it much easier to write your hypothesis, which ultimately helps your research.

Now it's easier than ever to streamline your research workflow with SciSpace Discover . Its integrated, comprehensive end-to-end platform for research allows scholars to easily discover, write and publish their research and fosters collaboration.

It includes everything you need, including a repository of over 270 million research papers across disciplines, SEO-optimized summaries and public profiles to show your expertise and experience.

If you found these tips on writing a research hypothesis useful, head over to our blog on Statistical Hypothesis Testing to learn about the top researchers, papers, and institutions in this domain.

Frequently Asked Questions (FAQs)

1. what is the definition of hypothesis.

According to the Oxford dictionary, a hypothesis is defined as “An idea or explanation of something that is based on a few known facts, but that has not yet been proved to be true or correct”.

2. What is an example of hypothesis?

The hypothesis is a statement that proposes a relationship between two or more variables. An example: "If we increase the number of new users who join our platform by 25%, then we will see an increase in revenue."

3. What is an example of null hypothesis?

A null hypothesis is a statement that there is no relationship between two variables. The null hypothesis is written as H0. The null hypothesis states that there is no effect. For example, if you're studying whether or not a particular type of exercise increases strength, your null hypothesis will be "there is no difference in strength between people who exercise and people who don't."

4. What are the types of research?

• Fundamental research

• Applied research

• Qualitative research

• Quantitative research

• Mixed research

• Exploratory research

• Longitudinal research

• Cross-sectional research

• Field research

• Laboratory research

• Fixed research

• Flexible research

• Action research

• Policy research

• Classification research

• Comparative research

• Causal research

• Inductive research

• Deductive research

5. How to write a hypothesis?

• Your hypothesis should be able to predict the relationship and outcome.

• Avoid wordiness by keeping it simple and brief.

• Your hypothesis should contain observable and testable outcomes.

• Your hypothesis should be relevant to the research question.

6. What are the 2 types of hypothesis?

• Null hypotheses are used to test the claim that "there is no difference between two groups of data".

• Alternative hypotheses test the claim that "there is a difference between two data groups".

7. Difference between research question and research hypothesis?

A research question is a broad, open-ended question you will try to answer through your research. A hypothesis is a statement based on prior research or theory that you expect to be true due to your study. Example - Research question: What are the factors that influence the adoption of the new technology? Research hypothesis: There is a positive relationship between age, education and income level with the adoption of the new technology.

8. What is plural for hypothesis?

The plural of hypothesis is hypotheses. Here's an example of how it would be used in a statement, "Numerous well-considered hypotheses are presented in this part, and they are supported by tables and figures that are well-illustrated."

9. What is the red queen hypothesis?

The red queen hypothesis in evolutionary biology states that species must constantly evolve to avoid extinction because if they don't, they will be outcompeted by other species that are evolving. Leigh Van Valen first proposed it in 1973; since then, it has been tested and substantiated many times.

10. Who is known as the father of null hypothesis?

The father of the null hypothesis is Sir Ronald Fisher. He published a paper in 1925 that introduced the concept of null hypothesis testing, and he was also the first to use the term itself.

11. When to reject null hypothesis?

You need to find a significant difference between your two populations to reject the null hypothesis. You can determine that by running statistical tests such as an independent sample t-test or a dependent sample t-test. You should reject the null hypothesis if the p-value is less than 0.05.

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What Is a Hypothesis and How Do I Write One?

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General Education

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Think about something strange and unexplainable in your life. Maybe you get a headache right before it rains, or maybe you think your favorite sports team wins when you wear a certain color. If you wanted to see whether these are just coincidences or scientific fact, you would form a hypothesis, then create an experiment to see whether that hypothesis is true or not.

But what is a hypothesis, anyway? If you’re not sure about what a hypothesis is--or how to test for one!--you’re in the right place. This article will teach you everything you need to know about hypotheses, including: 

  • Defining the term “hypothesis” 
  • Providing hypothesis examples 
  • Giving you tips for how to write your own hypothesis

So let’s get started!

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What Is a Hypothesis?

Merriam Webster defines a hypothesis as “an assumption or concession made for the sake of argument.” In other words, a hypothesis is an educated guess . Scientists make a reasonable assumption--or a hypothesis--then design an experiment to test whether it’s true or not. Keep in mind that in science, a hypothesis should be testable. You have to be able to design an experiment that tests your hypothesis in order for it to be valid. 

As you could assume from that statement, it’s easy to make a bad hypothesis. But when you’re holding an experiment, it’s even more important that your guesses be good...after all, you’re spending time (and maybe money!) to figure out more about your observation. That’s why we refer to a hypothesis as an educated guess--good hypotheses are based on existing data and research to make them as sound as possible.

Hypotheses are one part of what’s called the scientific method .  Every (good) experiment or study is based in the scientific method. The scientific method gives order and structure to experiments and ensures that interference from scientists or outside influences does not skew the results. It’s important that you understand the concepts of the scientific method before holding your own experiment. Though it may vary among scientists, the scientific method is generally made up of six steps (in order):

  • Observation
  • Asking questions
  • Forming a hypothesis
  • Analyze the data
  • Communicate your results

You’ll notice that the hypothesis comes pretty early on when conducting an experiment. That’s because experiments work best when they’re trying to answer one specific question. And you can’t conduct an experiment until you know what you’re trying to prove!

Independent and Dependent Variables 

After doing your research, you’re ready for another important step in forming your hypothesis: identifying variables. Variables are basically any factor that could influence the outcome of your experiment . Variables have to be measurable and related to the topic being studied.

There are two types of variables:  independent variables and dependent variables. I ndependent variables remain constant . For example, age is an independent variable; it will stay the same, and researchers can look at different ages to see if it has an effect on the dependent variable. 

Speaking of dependent variables... dependent variables are subject to the influence of the independent variable , meaning that they are not constant. Let’s say you want to test whether a person’s age affects how much sleep they need. In that case, the independent variable is age (like we mentioned above), and the dependent variable is how much sleep a person gets. 

Variables will be crucial in writing your hypothesis. You need to be able to identify which variable is which, as both the independent and dependent variables will be written into your hypothesis. For instance, in a study about exercise, the independent variable might be the speed at which the respondents walk for thirty minutes, and the dependent variable would be their heart rate. In your study and in your hypothesis, you’re trying to understand the relationship between the two variables.

Elements of a Good Hypothesis

The best hypotheses start by asking the right questions . For instance, if you’ve observed that the grass is greener when it rains twice a week, you could ask what kind of grass it is, what elevation it’s at, and if the grass across the street responds to rain in the same way. Any of these questions could become the backbone of experiments to test why the grass gets greener when it rains fairly frequently.

As you’re asking more questions about your first observation, make sure you’re also making more observations . If it doesn’t rain for two weeks and the grass still looks green, that’s an important observation that could influence your hypothesis. You'll continue observing all throughout your experiment, but until the hypothesis is finalized, every observation should be noted.

Finally, you should consult secondary research before writing your hypothesis . Secondary research is comprised of results found and published by other people. You can usually find this information online or at your library. Additionally, m ake sure the research you find is credible and related to your topic. If you’re studying the correlation between rain and grass growth, it would help you to research rain patterns over the past twenty years for your county, published by a local agricultural association. You should also research the types of grass common in your area, the type of grass in your lawn, and whether anyone else has conducted experiments about your hypothesis. Also be sure you’re checking the quality of your research . Research done by a middle school student about what minerals can be found in rainwater would be less useful than an article published by a local university.

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Writing Your Hypothesis

Once you’ve considered all of the factors above, you’re ready to start writing your hypothesis. Hypotheses usually take a certain form when they’re written out in a research report.

When you boil down your hypothesis statement, you are writing down your best guess and not the question at hand . This means that your statement should be written as if it is fact already, even though you are simply testing it.

The reason for this is that, after you have completed your study, you'll either accept or reject your if-then or your null hypothesis. All hypothesis testing examples should be measurable and able to be confirmed or denied. You cannot confirm a question, only a statement! 

In fact, you come up with hypothesis examples all the time! For instance, when you guess on the outcome of a basketball game, you don’t say, “Will the Miami Heat beat the Boston Celtics?” but instead, “I think the Miami Heat will beat the Boston Celtics.” You state it as if it is already true, even if it turns out you’re wrong. You do the same thing when writing your hypothesis.

Additionally, keep in mind that hypotheses can range from very specific to very broad.  These hypotheses can be specific, but if your hypothesis testing examples involve a broad range of causes and effects, your hypothesis can also be broad.  

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The Two Types of Hypotheses

Now that you understand what goes into a hypothesis, it’s time to look more closely at the two most common types of hypothesis: the if-then hypothesis and the null hypothesis.

#1: If-Then Hypotheses

First of all, if-then hypotheses typically follow this formula:

If ____ happens, then ____ will happen.

The goal of this type of hypothesis is to test the causal relationship between the independent and dependent variable. It’s fairly simple, and each hypothesis can vary in how detailed it can be. We create if-then hypotheses all the time with our daily predictions. Here are some examples of hypotheses that use an if-then structure from daily life: 

  • If I get enough sleep, I’ll be able to get more work done tomorrow.
  • If the bus is on time, I can make it to my friend’s birthday party. 
  • If I study every night this week, I’ll get a better grade on my exam. 

In each of these situations, you’re making a guess on how an independent variable (sleep, time, or studying) will affect a dependent variable (the amount of work you can do, making it to a party on time, or getting better grades). 

You may still be asking, “What is an example of a hypothesis used in scientific research?” Take one of the hypothesis examples from a real-world study on whether using technology before bed affects children’s sleep patterns. The hypothesis read s:

“We hypothesized that increased hours of tablet- and phone-based screen time at bedtime would be inversely correlated with sleep quality and child attention.”

It might not look like it, but this is an if-then statement. The researchers basically said, “If children have more screen usage at bedtime, then their quality of sleep and attention will be worse.” The sleep quality and attention are the dependent variables and the screen usage is the independent variable. (Usually, the independent variable comes after the “if” and the dependent variable comes after the “then,” as it is the independent variable that affects the dependent variable.) This is an excellent example of how flexible hypothesis statements can be, as long as the general idea of “if-then” and the independent and dependent variables are present.

#2: Null Hypotheses

Your if-then hypothesis is not the only one needed to complete a successful experiment, however. You also need a null hypothesis to test it against. In its most basic form, the null hypothesis is the opposite of your if-then hypothesis . When you write your null hypothesis, you are writing a hypothesis that suggests that your guess is not true, and that the independent and dependent variables have no relationship .

One null hypothesis for the cell phone and sleep study from the last section might say: 

“If children have more screen usage at bedtime, their quality of sleep and attention will not be worse.” 

In this case, this is a null hypothesis because it’s asking the opposite of the original thesis! 

Conversely, if your if-then hypothesis suggests that your two variables have no relationship, then your null hypothesis would suggest that there is one. So, pretend that there is a study that is asking the question, “Does the amount of followers on Instagram influence how long people spend on the app?” The independent variable is the amount of followers, and the dependent variable is the time spent. But if you, as the researcher, don’t think there is a relationship between the number of followers and time spent, you might write an if-then hypothesis that reads:

“If people have many followers on Instagram, they will not spend more time on the app than people who have less.”

In this case, the if-then suggests there isn’t a relationship between the variables. In that case, one of the null hypothesis examples might say:

“If people have many followers on Instagram, they will spend more time on the app than people who have less.”

You then test both the if-then and the null hypothesis to gauge if there is a relationship between the variables, and if so, how much of a relationship. 

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4 Tips to Write the Best Hypothesis

If you’re going to take the time to hold an experiment, whether in school or by yourself, you’re also going to want to take the time to make sure your hypothesis is a good one. The best hypotheses have four major elements in common: plausibility, defined concepts, observability, and general explanation.

#1: Plausibility

At first glance, this quality of a hypothesis might seem obvious. When your hypothesis is plausible, that means it’s possible given what we know about science and general common sense. However, improbable hypotheses are more common than you might think. 

Imagine you’re studying weight gain and television watching habits. If you hypothesize that people who watch more than  twenty hours of television a week will gain two hundred pounds or more over the course of a year, this might be improbable (though it’s potentially possible). Consequently, c ommon sense can tell us the results of the study before the study even begins.

Improbable hypotheses generally go against  science, as well. Take this hypothesis example: 

“If a person smokes one cigarette a day, then they will have lungs just as healthy as the average person’s.” 

This hypothesis is obviously untrue, as studies have shown again and again that cigarettes negatively affect lung health. You must be careful that your hypotheses do not reflect your own personal opinion more than they do scientifically-supported findings. This plausibility points to the necessity of research before the hypothesis is written to make sure that your hypothesis has not already been disproven.

#2: Defined Concepts

The more advanced you are in your studies, the more likely that the terms you’re using in your hypothesis are specific to a limited set of knowledge. One of the hypothesis testing examples might include the readability of printed text in newspapers, where you might use words like “kerning” and “x-height.” Unless your readers have a background in graphic design, it’s likely that they won’t know what you mean by these terms. Thus, it’s important to either write what they mean in the hypothesis itself or in the report before the hypothesis.

Here’s what we mean. Which of the following sentences makes more sense to the common person?

If the kerning is greater than average, more words will be read per minute.

If the space between letters is greater than average, more words will be read per minute.

For people reading your report that are not experts in typography, simply adding a few more words will be helpful in clarifying exactly what the experiment is all about. It’s always a good idea to make your research and findings as accessible as possible. 

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Good hypotheses ensure that you can observe the results. 

#3: Observability

In order to measure the truth or falsity of your hypothesis, you must be able to see your variables and the way they interact. For instance, if your hypothesis is that the flight patterns of satellites affect the strength of certain television signals, yet you don’t have a telescope to view the satellites or a television to monitor the signal strength, you cannot properly observe your hypothesis and thus cannot continue your study.

Some variables may seem easy to observe, but if you do not have a system of measurement in place, you cannot observe your hypothesis properly. Here’s an example: if you’re experimenting on the effect of healthy food on overall happiness, but you don’t have a way to monitor and measure what “overall happiness” means, your results will not reflect the truth. Monitoring how often someone smiles for a whole day is not reasonably observable, but having the participants state how happy they feel on a scale of one to ten is more observable. 

In writing your hypothesis, always keep in mind how you'll execute the experiment.

#4: Generalizability 

Perhaps you’d like to study what color your best friend wears the most often by observing and documenting the colors she wears each day of the week. This might be fun information for her and you to know, but beyond you two, there aren’t many people who could benefit from this experiment. When you start an experiment, you should note how generalizable your findings may be if they are confirmed. Generalizability is basically how common a particular phenomenon is to other people’s everyday life.

Let’s say you’re asking a question about the health benefits of eating an apple for one day only, you need to realize that the experiment may be too specific to be helpful. It does not help to explain a phenomenon that many people experience. If you find yourself with too specific of a hypothesis, go back to asking the big question: what is it that you want to know, and what do you think will happen between your two variables?

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Hypothesis Testing Examples

We know it can be hard to write a good hypothesis unless you’ve seen some good hypothesis examples. We’ve included four hypothesis examples based on some made-up experiments. Use these as templates or launch pads for coming up with your own hypotheses.

Experiment #1: Students Studying Outside (Writing a Hypothesis)

You are a student at PrepScholar University. When you walk around campus, you notice that, when the temperature is above 60 degrees, more students study in the quad. You want to know when your fellow students are more likely to study outside. With this information, how do you make the best hypothesis possible?

You must remember to make additional observations and do secondary research before writing your hypothesis. In doing so, you notice that no one studies outside when it’s 75 degrees and raining, so this should be included in your experiment. Also, studies done on the topic beforehand suggested that students are more likely to study in temperatures less than 85 degrees. With this in mind, you feel confident that you can identify your variables and write your hypotheses:

If-then: “If the temperature in Fahrenheit is less than 60 degrees, significantly fewer students will study outside.”

Null: “If the temperature in Fahrenheit is less than 60 degrees, the same number of students will study outside as when it is more than 60 degrees.”

These hypotheses are plausible, as the temperatures are reasonably within the bounds of what is possible. The number of people in the quad is also easily observable. It is also not a phenomenon specific to only one person or at one time, but instead can explain a phenomenon for a broader group of people.

To complete this experiment, you pick the month of October to observe the quad. Every day (except on the days where it’s raining)from 3 to 4 PM, when most classes have released for the day, you observe how many people are on the quad. You measure how many people come  and how many leave. You also write down the temperature on the hour. 

After writing down all of your observations and putting them on a graph, you find that the most students study on the quad when it is 70 degrees outside, and that the number of students drops a lot once the temperature reaches 60 degrees or below. In this case, your research report would state that you accept or “failed to reject” your first hypothesis with your findings.

Experiment #2: The Cupcake Store (Forming a Simple Experiment)

Let’s say that you work at a bakery. You specialize in cupcakes, and you make only two colors of frosting: yellow and purple. You want to know what kind of customers are more likely to buy what kind of cupcake, so you set up an experiment. Your independent variable is the customer’s gender, and the dependent variable is the color of the frosting. What is an example of a hypothesis that might answer the question of this study?

Here’s what your hypotheses might look like: 

If-then: “If customers’ gender is female, then they will buy more yellow cupcakes than purple cupcakes.”

Null: “If customers’ gender is female, then they will be just as likely to buy purple cupcakes as yellow cupcakes.”

This is a pretty simple experiment! It passes the test of plausibility (there could easily be a difference), defined concepts (there’s nothing complicated about cupcakes!), observability (both color and gender can be easily observed), and general explanation ( this would potentially help you make better business decisions ).

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Experiment #3: Backyard Bird Feeders (Integrating Multiple Variables and Rejecting the If-Then Hypothesis)

While watching your backyard bird feeder, you realized that different birds come on the days when you change the types of seeds. You decide that you want to see more cardinals in your backyard, so you decide to see what type of food they like the best and set up an experiment. 

However, one morning, you notice that, while some cardinals are present, blue jays are eating out of your backyard feeder filled with millet. You decide that, of all of the other birds, you would like to see the blue jays the least. This means you'll have more than one variable in your hypothesis. Your new hypotheses might look like this: 

If-then: “If sunflower seeds are placed in the bird feeders, then more cardinals will come than blue jays. If millet is placed in the bird feeders, then more blue jays will come than cardinals.”

Null: “If either sunflower seeds or millet are placed in the bird, equal numbers of cardinals and blue jays will come.”

Through simple observation, you actually find that cardinals come as often as blue jays when sunflower seeds or millet is in the bird feeder. In this case, you would reject your “if-then” hypothesis and “fail to reject” your null hypothesis . You cannot accept your first hypothesis, because it’s clearly not true. Instead you found that there was actually no relation between your different variables. Consequently, you would need to run more experiments with different variables to see if the new variables impact the results.

Experiment #4: In-Class Survey (Including an Alternative Hypothesis)

You’re about to give a speech in one of your classes about the importance of paying attention. You want to take this opportunity to test a hypothesis you’ve had for a while: 

If-then: If students sit in the first two rows of the classroom, then they will listen better than students who do not.

Null: If students sit in the first two rows of the classroom, then they will not listen better or worse than students who do not.

You give your speech and then ask your teacher if you can hand out a short survey to the class. On the survey, you’ve included questions about some of the topics you talked about. When you get back the results, you’re surprised to see that not only do the students in the first two rows not pay better attention, but they also scored worse than students in other parts of the classroom! Here, both your if-then and your null hypotheses are not representative of your findings. What do you do?

This is when you reject both your if-then and null hypotheses and instead create an alternative hypothesis . This type of hypothesis is used in the rare circumstance that neither of your hypotheses is able to capture your findings . Now you can use what you’ve learned to draft new hypotheses and test again! 

Key Takeaways: Hypothesis Writing

The more comfortable you become with writing hypotheses, the better they will become. The structure of hypotheses is flexible and may need to be changed depending on what topic you are studying. The most important thing to remember is the purpose of your hypothesis and the difference between the if-then and the null . From there, in forming your hypothesis, you should constantly be asking questions, making observations, doing secondary research, and considering your variables. After you have written your hypothesis, be sure to edit it so that it is plausible, clearly defined, observable, and helpful in explaining a general phenomenon.

Writing a hypothesis is something that everyone, from elementary school children competing in a science fair to professional scientists in a lab, needs to know how to do. Hypotheses are vital in experiments and in properly executing the scientific method . When done correctly, hypotheses will set up your studies for success and help you to understand the world a little better, one experiment at a time.

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What’s Next?

If you’re studying for the science portion of the ACT, there’s definitely a lot you need to know. We’ve got the tools to help, though! Start by checking out our ultimate study guide for the ACT Science subject test. Once you read through that, be sure to download our recommended ACT Science practice tests , since they’re one of the most foolproof ways to improve your score. (And don’t forget to check out our expert guide book , too.)

If you love science and want to major in a scientific field, you should start preparing in high school . Here are the science classes you should take to set yourself up for success.

If you’re trying to think of science experiments you can do for class (or for a science fair!), here’s a list of 37 awesome science experiments you can do at home

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How to Write a Great Hypothesis

Hypothesis Definition, Format, Examples, and Tips

Verywell / Alex Dos Diaz

  • The Scientific Method

Hypothesis Format

Falsifiability of a hypothesis.

  • Operationalization

Hypothesis Types

Hypotheses examples.

  • Collecting Data

A hypothesis is a tentative statement about the relationship between two or more variables. It is a specific, testable prediction about what you expect to happen in a study. It is a preliminary answer to your question that helps guide the research process.

Consider a study designed to examine the relationship between sleep deprivation and test performance. The hypothesis might be: "This study is designed to assess the hypothesis that sleep-deprived people will perform worse on a test than individuals who are not sleep-deprived."

At a Glance

A hypothesis is crucial to scientific research because it offers a clear direction for what the researchers are looking to find. This allows them to design experiments to test their predictions and add to our scientific knowledge about the world. This article explores how a hypothesis is used in psychology research, how to write a good hypothesis, and the different types of hypotheses you might use.

The Hypothesis in the Scientific Method

In the scientific method , whether it involves research in psychology, biology, or some other area, a hypothesis represents what the researchers think will happen in an experiment. The scientific method involves the following steps:

  • Forming a question
  • Performing background research
  • Creating a hypothesis
  • Designing an experiment
  • Collecting data
  • Analyzing the results
  • Drawing conclusions
  • Communicating the results

The hypothesis is a prediction, but it involves more than a guess. Most of the time, the hypothesis begins with a question which is then explored through background research. At this point, researchers then begin to develop a testable hypothesis.

Unless you are creating an exploratory study, your hypothesis should always explain what you  expect  to happen.

In a study exploring the effects of a particular drug, the hypothesis might be that researchers expect the drug to have some type of effect on the symptoms of a specific illness. In psychology, the hypothesis might focus on how a certain aspect of the environment might influence a particular behavior.

Remember, a hypothesis does not have to be correct. While the hypothesis predicts what the researchers expect to see, the goal of the research is to determine whether this guess is right or wrong. When conducting an experiment, researchers might explore numerous factors to determine which ones might contribute to the ultimate outcome.

In many cases, researchers may find that the results of an experiment  do not  support the original hypothesis. When writing up these results, the researchers might suggest other options that should be explored in future studies.

In many cases, researchers might draw a hypothesis from a specific theory or build on previous research. For example, prior research has shown that stress can impact the immune system. So a researcher might hypothesize: "People with high-stress levels will be more likely to contract a common cold after being exposed to the virus than people who have low-stress levels."

In other instances, researchers might look at commonly held beliefs or folk wisdom. "Birds of a feather flock together" is one example of folk adage that a psychologist might try to investigate. The researcher might pose a specific hypothesis that "People tend to select romantic partners who are similar to them in interests and educational level."

Elements of a Good Hypothesis

So how do you write a good hypothesis? When trying to come up with a hypothesis for your research or experiments, ask yourself the following questions:

  • Is your hypothesis based on your research on a topic?
  • Can your hypothesis be tested?
  • Does your hypothesis include independent and dependent variables?

Before you come up with a specific hypothesis, spend some time doing background research. Once you have completed a literature review, start thinking about potential questions you still have. Pay attention to the discussion section in the  journal articles you read . Many authors will suggest questions that still need to be explored.

How to Formulate a Good Hypothesis

To form a hypothesis, you should take these steps:

  • Collect as many observations about a topic or problem as you can.
  • Evaluate these observations and look for possible causes of the problem.
  • Create a list of possible explanations that you might want to explore.
  • After you have developed some possible hypotheses, think of ways that you could confirm or disprove each hypothesis through experimentation. This is known as falsifiability.

In the scientific method ,  falsifiability is an important part of any valid hypothesis. In order to test a claim scientifically, it must be possible that the claim could be proven false.

Students sometimes confuse the idea of falsifiability with the idea that it means that something is false, which is not the case. What falsifiability means is that  if  something was false, then it is possible to demonstrate that it is false.

One of the hallmarks of pseudoscience is that it makes claims that cannot be refuted or proven false.

The Importance of Operational Definitions

A variable is a factor or element that can be changed and manipulated in ways that are observable and measurable. However, the researcher must also define how the variable will be manipulated and measured in the study.

Operational definitions are specific definitions for all relevant factors in a study. This process helps make vague or ambiguous concepts detailed and measurable.

For example, a researcher might operationally define the variable " test anxiety " as the results of a self-report measure of anxiety experienced during an exam. A "study habits" variable might be defined by the amount of studying that actually occurs as measured by time.

These precise descriptions are important because many things can be measured in various ways. Clearly defining these variables and how they are measured helps ensure that other researchers can replicate your results.

Replicability

One of the basic principles of any type of scientific research is that the results must be replicable.

Replication means repeating an experiment in the same way to produce the same results. By clearly detailing the specifics of how the variables were measured and manipulated, other researchers can better understand the results and repeat the study if needed.

Some variables are more difficult than others to define. For example, how would you operationally define a variable such as aggression ? For obvious ethical reasons, researchers cannot create a situation in which a person behaves aggressively toward others.

To measure this variable, the researcher must devise a measurement that assesses aggressive behavior without harming others. The researcher might utilize a simulated task to measure aggressiveness in this situation.

Hypothesis Checklist

  • Does your hypothesis focus on something that you can actually test?
  • Does your hypothesis include both an independent and dependent variable?
  • Can you manipulate the variables?
  • Can your hypothesis be tested without violating ethical standards?

The hypothesis you use will depend on what you are investigating and hoping to find. Some of the main types of hypotheses that you might use include:

  • Simple hypothesis : This type of hypothesis suggests there is a relationship between one independent variable and one dependent variable.
  • Complex hypothesis : This type suggests a relationship between three or more variables, such as two independent and dependent variables.
  • Null hypothesis : This hypothesis suggests no relationship exists between two or more variables.
  • Alternative hypothesis : This hypothesis states the opposite of the null hypothesis.
  • Statistical hypothesis : This hypothesis uses statistical analysis to evaluate a representative population sample and then generalizes the findings to the larger group.
  • Logical hypothesis : This hypothesis assumes a relationship between variables without collecting data or evidence.

A hypothesis often follows a basic format of "If {this happens} then {this will happen}." One way to structure your hypothesis is to describe what will happen to the  dependent variable  if you change the  independent variable .

The basic format might be: "If {these changes are made to a certain independent variable}, then we will observe {a change in a specific dependent variable}."

A few examples of simple hypotheses:

  • "Students who eat breakfast will perform better on a math exam than students who do not eat breakfast."
  • "Students who experience test anxiety before an English exam will get lower scores than students who do not experience test anxiety."​
  • "Motorists who talk on the phone while driving will be more likely to make errors on a driving course than those who do not talk on the phone."
  • "Children who receive a new reading intervention will have higher reading scores than students who do not receive the intervention."

Examples of a complex hypothesis include:

  • "People with high-sugar diets and sedentary activity levels are more likely to develop depression."
  • "Younger people who are regularly exposed to green, outdoor areas have better subjective well-being than older adults who have limited exposure to green spaces."

Examples of a null hypothesis include:

  • "There is no difference in anxiety levels between people who take St. John's wort supplements and those who do not."
  • "There is no difference in scores on a memory recall task between children and adults."
  • "There is no difference in aggression levels between children who play first-person shooter games and those who do not."

Examples of an alternative hypothesis:

  • "People who take St. John's wort supplements will have less anxiety than those who do not."
  • "Adults will perform better on a memory task than children."
  • "Children who play first-person shooter games will show higher levels of aggression than children who do not." 

Collecting Data on Your Hypothesis

Once a researcher has formed a testable hypothesis, the next step is to select a research design and start collecting data. The research method depends largely on exactly what they are studying. There are two basic types of research methods: descriptive research and experimental research.

Descriptive Research Methods

Descriptive research such as  case studies ,  naturalistic observations , and surveys are often used when  conducting an experiment is difficult or impossible. These methods are best used to describe different aspects of a behavior or psychological phenomenon.

Once a researcher has collected data using descriptive methods, a  correlational study  can examine how the variables are related. This research method might be used to investigate a hypothesis that is difficult to test experimentally.

Experimental Research Methods

Experimental methods  are used to demonstrate causal relationships between variables. In an experiment, the researcher systematically manipulates a variable of interest (known as the independent variable) and measures the effect on another variable (known as the dependent variable).

Unlike correlational studies, which can only be used to determine if there is a relationship between two variables, experimental methods can be used to determine the actual nature of the relationship—whether changes in one variable actually  cause  another to change.

The hypothesis is a critical part of any scientific exploration. It represents what researchers expect to find in a study or experiment. In situations where the hypothesis is unsupported by the research, the research still has value. Such research helps us better understand how different aspects of the natural world relate to one another. It also helps us develop new hypotheses that can then be tested in the future.

Thompson WH, Skau S. On the scope of scientific hypotheses .  R Soc Open Sci . 2023;10(8):230607. doi:10.1098/rsos.230607

Taran S, Adhikari NKJ, Fan E. Falsifiability in medicine: what clinicians can learn from Karl Popper [published correction appears in Intensive Care Med. 2021 Jun 17;:].  Intensive Care Med . 2021;47(9):1054-1056. doi:10.1007/s00134-021-06432-z

Eyler AA. Research Methods for Public Health . 1st ed. Springer Publishing Company; 2020. doi:10.1891/9780826182067.0004

Nosek BA, Errington TM. What is replication ?  PLoS Biol . 2020;18(3):e3000691. doi:10.1371/journal.pbio.3000691

Aggarwal R, Ranganathan P. Study designs: Part 2 - Descriptive studies .  Perspect Clin Res . 2019;10(1):34-36. doi:10.4103/picr.PICR_154_18

Nevid J. Psychology: Concepts and Applications. Wadworth, 2013.

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Educational resources and simple solutions for your research journey

Research hypothesis: What it is, how to write it, types, and examples

What is a Research Hypothesis: How to Write it, Types, and Examples

hypothesis is an educated guess

Any research begins with a research question and a research hypothesis . A research question alone may not suffice to design the experiment(s) needed to answer it. A hypothesis is central to the scientific method. But what is a hypothesis ? A hypothesis is a testable statement that proposes a possible explanation to a phenomenon, and it may include a prediction. Next, you may ask what is a research hypothesis ? Simply put, a research hypothesis is a prediction or educated guess about the relationship between the variables that you want to investigate.  

It is important to be thorough when developing your research hypothesis. Shortcomings in the framing of a hypothesis can affect the study design and the results. A better understanding of the research hypothesis definition and characteristics of a good hypothesis will make it easier for you to develop your own hypothesis for your research. Let’s dive in to know more about the types of research hypothesis , how to write a research hypothesis , and some research hypothesis examples .  

Table of Contents

What is a hypothesis ?  

A hypothesis is based on the existing body of knowledge in a study area. Framed before the data are collected, a hypothesis states the tentative relationship between independent and dependent variables, along with a prediction of the outcome.  

What is a research hypothesis ?  

Young researchers starting out their journey are usually brimming with questions like “ What is a hypothesis ?” “ What is a research hypothesis ?” “How can I write a good research hypothesis ?”   

A research hypothesis is a statement that proposes a possible explanation for an observable phenomenon or pattern. It guides the direction of a study and predicts the outcome of the investigation. A research hypothesis is testable, i.e., it can be supported or disproven through experimentation or observation.     

hypothesis is an educated guess

Characteristics of a good hypothesis  

Here are the characteristics of a good hypothesis :  

  • Clearly formulated and free of language errors and ambiguity  
  • Concise and not unnecessarily verbose  
  • Has clearly defined variables  
  • Testable and stated in a way that allows for it to be disproven  
  • Can be tested using a research design that is feasible, ethical, and practical   
  • Specific and relevant to the research problem  
  • Rooted in a thorough literature search  
  • Can generate new knowledge or understanding.  

How to create an effective research hypothesis  

A study begins with the formulation of a research question. A researcher then performs background research. This background information forms the basis for building a good research hypothesis . The researcher then performs experiments, collects, and analyzes the data, interprets the findings, and ultimately, determines if the findings support or negate the original hypothesis.  

Let’s look at each step for creating an effective, testable, and good research hypothesis :  

  • Identify a research problem or question: Start by identifying a specific research problem.   
  • Review the literature: Conduct an in-depth review of the existing literature related to the research problem to grasp the current knowledge and gaps in the field.   
  • Formulate a clear and testable hypothesis : Based on the research question, use existing knowledge to form a clear and testable hypothesis . The hypothesis should state a predicted relationship between two or more variables that can be measured and manipulated. Improve the original draft till it is clear and meaningful.  
  • State the null hypothesis: The null hypothesis is a statement that there is no relationship between the variables you are studying.   
  • Define the population and sample: Clearly define the population you are studying and the sample you will be using for your research.  
  • Select appropriate methods for testing the hypothesis: Select appropriate research methods, such as experiments, surveys, or observational studies, which will allow you to test your research hypothesis .  

Remember that creating a research hypothesis is an iterative process, i.e., you might have to revise it based on the data you collect. You may need to test and reject several hypotheses before answering the research problem.  

How to write a research hypothesis  

When you start writing a research hypothesis , you use an “if–then” statement format, which states the predicted relationship between two or more variables. Clearly identify the independent variables (the variables being changed) and the dependent variables (the variables being measured), as well as the population you are studying. Review and revise your hypothesis as needed.  

An example of a research hypothesis in this format is as follows:  

“ If [athletes] follow [cold water showers daily], then their [endurance] increases.”  

Population: athletes  

Independent variable: daily cold water showers  

Dependent variable: endurance  

You may have understood the characteristics of a good hypothesis . But note that a research hypothesis is not always confirmed; a researcher should be prepared to accept or reject the hypothesis based on the study findings.  

hypothesis is an educated guess

Research hypothesis checklist  

Following from above, here is a 10-point checklist for a good research hypothesis :  

  • Testable: A research hypothesis should be able to be tested via experimentation or observation.  
  • Specific: A research hypothesis should clearly state the relationship between the variables being studied.  
  • Based on prior research: A research hypothesis should be based on existing knowledge and previous research in the field.  
  • Falsifiable: A research hypothesis should be able to be disproven through testing.  
  • Clear and concise: A research hypothesis should be stated in a clear and concise manner.  
  • Logical: A research hypothesis should be logical and consistent with current understanding of the subject.  
  • Relevant: A research hypothesis should be relevant to the research question and objectives.  
  • Feasible: A research hypothesis should be feasible to test within the scope of the study.  
  • Reflects the population: A research hypothesis should consider the population or sample being studied.  
  • Uncomplicated: A good research hypothesis is written in a way that is easy for the target audience to understand.  

By following this research hypothesis checklist , you will be able to create a research hypothesis that is strong, well-constructed, and more likely to yield meaningful results.  

Research hypothesis: What it is, how to write it, types, and examples

Types of research hypothesis  

Different types of research hypothesis are used in scientific research:  

1. Null hypothesis:

A null hypothesis states that there is no change in the dependent variable due to changes to the independent variable. This means that the results are due to chance and are not significant. A null hypothesis is denoted as H0 and is stated as the opposite of what the alternative hypothesis states.   

Example: “ The newly identified virus is not zoonotic .”  

2. Alternative hypothesis:

This states that there is a significant difference or relationship between the variables being studied. It is denoted as H1 or Ha and is usually accepted or rejected in favor of the null hypothesis.  

Example: “ The newly identified virus is zoonotic .”  

3. Directional hypothesis :

This specifies the direction of the relationship or difference between variables; therefore, it tends to use terms like increase, decrease, positive, negative, more, or less.   

Example: “ The inclusion of intervention X decreases infant mortality compared to the original treatment .”   

4. Non-directional hypothesis:

While it does not predict the exact direction or nature of the relationship between the two variables, a non-directional hypothesis states the existence of a relationship or difference between variables but not the direction, nature, or magnitude of the relationship. A non-directional hypothesis may be used when there is no underlying theory or when findings contradict previous research.  

Example, “ Cats and dogs differ in the amount of affection they express .”  

5. Simple hypothesis :

A simple hypothesis only predicts the relationship between one independent and another independent variable.  

Example: “ Applying sunscreen every day slows skin aging .”  

6 . Complex hypothesis :

A complex hypothesis states the relationship or difference between two or more independent and dependent variables.   

Example: “ Applying sunscreen every day slows skin aging, reduces sun burn, and reduces the chances of skin cancer .” (Here, the three dependent variables are slowing skin aging, reducing sun burn, and reducing the chances of skin cancer.)  

7. Associative hypothesis:  

An associative hypothesis states that a change in one variable results in the change of the other variable. The associative hypothesis defines interdependency between variables.  

Example: “ There is a positive association between physical activity levels and overall health .”  

8 . Causal hypothesis:

A causal hypothesis proposes a cause-and-effect interaction between variables.  

Example: “ Long-term alcohol use causes liver damage .”  

Note that some of the types of research hypothesis mentioned above might overlap. The types of hypothesis chosen will depend on the research question and the objective of the study.  

hypothesis is an educated guess

Research hypothesis examples  

Here are some good research hypothesis examples :  

“The use of a specific type of therapy will lead to a reduction in symptoms of depression in individuals with a history of major depressive disorder.”  

“Providing educational interventions on healthy eating habits will result in weight loss in overweight individuals.”  

“Plants that are exposed to certain types of music will grow taller than those that are not exposed to music.”  

“The use of the plant growth regulator X will lead to an increase in the number of flowers produced by plants.”  

Characteristics that make a research hypothesis weak are unclear variables, unoriginality, being too general or too vague, and being untestable. A weak hypothesis leads to weak research and improper methods.   

Some bad research hypothesis examples (and the reasons why they are “bad”) are as follows:  

“This study will show that treatment X is better than any other treatment . ” (This statement is not testable, too broad, and does not consider other treatments that may be effective.)  

“This study will prove that this type of therapy is effective for all mental disorders . ” (This statement is too broad and not testable as mental disorders are complex and different disorders may respond differently to different types of therapy.)  

“Plants can communicate with each other through telepathy . ” (This statement is not testable and lacks a scientific basis.)  

Importance of testable hypothesis  

If a research hypothesis is not testable, the results will not prove or disprove anything meaningful. The conclusions will be vague at best. A testable hypothesis helps a researcher focus on the study outcome and understand the implication of the question and the different variables involved. A testable hypothesis helps a researcher make precise predictions based on prior research.  

To be considered testable, there must be a way to prove that the hypothesis is true or false; further, the results of the hypothesis must be reproducible.  

Research hypothesis: What it is, how to write it, types, and examples

Frequently Asked Questions (FAQs) on research hypothesis  

1. What is the difference between research question and research hypothesis ?  

A research question defines the problem and helps outline the study objective(s). It is an open-ended statement that is exploratory or probing in nature. Therefore, it does not make predictions or assumptions. It helps a researcher identify what information to collect. A research hypothesis , however, is a specific, testable prediction about the relationship between variables. Accordingly, it guides the study design and data analysis approach.

2. When to reject null hypothesis ?

A null hypothesis should be rejected when the evidence from a statistical test shows that it is unlikely to be true. This happens when the test statistic (e.g., p -value) is less than the defined significance level (e.g., 0.05). Rejecting the null hypothesis does not necessarily mean that the alternative hypothesis is true; it simply means that the evidence found is not compatible with the null hypothesis.  

3. How can I be sure my hypothesis is testable?  

A testable hypothesis should be specific and measurable, and it should state a clear relationship between variables that can be tested with data. To ensure that your hypothesis is testable, consider the following:  

  • Clearly define the key variables in your hypothesis. You should be able to measure and manipulate these variables in a way that allows you to test the hypothesis.  
  • The hypothesis should predict a specific outcome or relationship between variables that can be measured or quantified.   
  • You should be able to collect the necessary data within the constraints of your study.  
  • It should be possible for other researchers to replicate your study, using the same methods and variables.   
  • Your hypothesis should be testable by using appropriate statistical analysis techniques, so you can draw conclusions, and make inferences about the population from the sample data.  
  • The hypothesis should be able to be disproven or rejected through the collection of data.  

4. How do I revise my research hypothesis if my data does not support it?  

If your data does not support your research hypothesis , you will need to revise it or develop a new one. You should examine your data carefully and identify any patterns or anomalies, re-examine your research question, and/or revisit your theory to look for any alternative explanations for your results. Based on your review of the data, literature, and theories, modify your research hypothesis to better align it with the results you obtained. Use your revised hypothesis to guide your research design and data collection. It is important to remain objective throughout the process.  

5. I am performing exploratory research. Do I need to formulate a research hypothesis?  

As opposed to “confirmatory” research, where a researcher has some idea about the relationship between the variables under investigation, exploratory research (or hypothesis-generating research) looks into a completely new topic about which limited information is available. Therefore, the researcher will not have any prior hypotheses. In such cases, a researcher will need to develop a post-hoc hypothesis. A post-hoc research hypothesis is generated after these results are known.  

6. How is a research hypothesis different from a research question?

A research question is an inquiry about a specific topic or phenomenon, typically expressed as a question. It seeks to explore and understand a particular aspect of the research subject. In contrast, a research hypothesis is a specific statement or prediction that suggests an expected relationship between variables. It is formulated based on existing knowledge or theories and guides the research design and data analysis.

7. Can a research hypothesis change during the research process?

Yes, research hypotheses can change during the research process. As researchers collect and analyze data, new insights and information may emerge that require modification or refinement of the initial hypotheses. This can be due to unexpected findings, limitations in the original hypotheses, or the need to explore additional dimensions of the research topic. Flexibility is crucial in research, allowing for adaptation and adjustment of hypotheses to align with the evolving understanding of the subject matter.

8. How many hypotheses should be included in a research study?

The number of research hypotheses in a research study varies depending on the nature and scope of the research. It is not necessary to have multiple hypotheses in every study. Some studies may have only one primary hypothesis, while others may have several related hypotheses. The number of hypotheses should be determined based on the research objectives, research questions, and the complexity of the research topic. It is important to ensure that the hypotheses are focused, testable, and directly related to the research aims.

9. Can research hypotheses be used in qualitative research?

Yes, research hypotheses can be used in qualitative research, although they are more commonly associated with quantitative research. In qualitative research, hypotheses may be formulated as tentative or exploratory statements that guide the investigation. Instead of testing hypotheses through statistical analysis, qualitative researchers may use the hypotheses to guide data collection and analysis, seeking to uncover patterns, themes, or relationships within the qualitative data. The emphasis in qualitative research is often on generating insights and understanding rather than confirming or rejecting specific research hypotheses through statistical testing.

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NOTIFICATIONS

Myths of the nature of science.

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People have ideas about science based on personal experiences, previous education, popular media and peer culture . Many of these ideas are commonly held misconceptions or myths about the nature of science. Here are some of the more common myths that are problematic in science education.

Myth: The scientific method Myth: Experiments are the main route to scientific knowledge Myth: Science and its methods can answer all questions Myth: Science proves ideas Myth: Science ideas are absolute and unchanging Myth: Science is a solitary pursuit Myth: Science is procedural more than creative Myth: Scientists are particularly objective Myth: Scientific conclusions are reviewed by others for accuracy Myth: Acceptance of new scientific knowledge is straightforward Myth: Science models ‘are real’ Myth: A hypothesis is an educated guess Myth: Hypotheses become theories that, in turn, become laws

Myth: The scientific method

Perhaps the most commonly held myth about the nature of science is that there is a universal scientific method, with a common series of steps that scientists follow. The steps usually include defining the problem, forming a hypothesis, making observations, testing the hypothesis, drawing conclusions and reporting results. In classrooms, students can be seen writing up the aim, hypothesis, method, results and conclusion.

In reality there is no single method of science. Scientific inquiry is not a matter of following a set of rules. It is fluid, reflexive, context dependent and unpredictable. Scientists approach and solve problems in lots of different ways using imagination, creativity, prior knowledge and perseverance.

See examples on the Hub

Scientists use a range of research methods:

  • Producing commercial quanitites of nanofibre
  • Carbon dioxide and the oceans
  • Volcanology methods

Myth: Experiments are the main route to scientific knowledge

Experiments are certainly a useful tool in science but they are not the main route to knowledge. True experiments involve a range of carefully controlled procedures accompanied by control and test groups and usually have as a primary goal the establishment of a cause and effect relationship.

Science does involve investigation of some sort, but experiments are just one of many different approaches used. In a number of science disciplines, such as geology, cosmology or medicine, experiments are either not possible, insufficient, unnecessary or unethical, So science also relies on approaches such as basic observations (such as astronomy) and historical exploration (such as paleontology and evolutionary biology.

Scientists use many diverse approaches other than experiments within the broad disciplines of science:

  • Monitoring kōura
  • From the smallest bones come the biggest secrets
  • Date a dinosaur
  • Developing the New Zealand geologic timescale
  • Planet hunting

Myth: Science and its methods can answer all questions

Science has achieved many amazing things, but it is not a cure-all for all the problems in society. Although it can provide some insights that may inform debate, science cannot answer ethical, moral, aesthetic, social and metaphysical questions. For instance, science and the resulting technology may be able to clone mammals, but other knowledge is needed (cultural, sociological and philosophical) to decide whether such cloning is moral and ethical. Not all questions can be investigated in a scientific manner.

Myth: Science proves ideas

Popular media often talks about ‘scientific proof’. However, accumulated evidence can never provide absolute proof – it can only ever provide support. A single negative finding, if confirmed, is enough to overturn a scientific hypothesis or theory. Rather than being proven ‘once and for all’, a hallmark of science is that it is subject to revision when new information is presented or when existing information is viewed in a new light.

How a scientific hypothesis or theory can be overturned:

  • Icebergs and glaciation
  • Investigating our fern flora origins
  • Ruffling ancient feathers: kiwi’s Malagasy cousin

Myth: Science ideas are absolute and unchanging

Some ideas in science are so well established and reliable and so well supported by accumulated evidence that they are unlikely to be thrown out, but even these ideas may be modified by new evidence or by the reinterpretation of existing evidence. Science knowledge is durable, but not absolute or fixed – a critical feature of science is that it is self-correcting – so we say that scientific knowledge is tentative. This can be most easily seen at the cutting edge of research and in areas like health and medicine where ideas may change as scientists try to figure out which explanations are the most accurate.

Myth: Science is a solitary pursuit

This myth fits the stereotypical image of a lone scientist working alone in a laboratory. In reality, only rarely does a scientific idea arise in the mind of an individual scientist to be validated by the individual alone and then accepted by the scientific community. The process of science is much more often the result of collaboration of a group of scientists. Most research takes too long, is too expensive and needs more knowledge and expertise than an individual scientist working alone. The Science Learning Hub repeatedly shows this collaboration.

Some more examples:

  • Dairy research methodologies
  • Working as a scientist
  • Collaborating in medical research
  • Collaborating in science
  • Science over time: Standing on the shoulders of giants

The activity Scientist introduction encourages students to take a closer look at a scientist’s background and work.

Nature of science

Collaboration is the action of working with someone to produce something and has mutual benefits for both parties. Collaboration can occur between individuals working in a team. It can also describe the way in which individuals or organisations work together on a project. In this case, the collaboration may only be a small part of the individuals’ or organisations’ overall goals and responsibilities.

Myth: Science is procedural more than creative

Many students see science as following a series of steps and being dry, uninspiring and unimaginative. The opposite is true. Creativity is found in all aspects of scientific research, from coming up with a question, creating a research design, interpreting and making sense of findings or looking at old data in new ways. Creativity is absolutely critical to science.

How creativity is critical to science:

  • The Majestic Samaúma – art meets science
  • Research design
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Myth: Scientists are particularly objective

We often assume scientists are always objective, but scientists do not bring empty heads to their research. Their background knowledge, experiences and the existing concepts they hold mean they can’t be objective. Like all observers, they have a myriad of preconceptions and biases that they will bring to every observation and interpretation they make.

If we confront the world with an empty head, then our experiences will be deservedly meaningless. Experience does not give concepts meaning. If anything, concepts give experience meaning. David Theobald, 1968.

Myth: Scientific conclusions are reviewed by others for accuracy

Limited research funds and time constraints do not allow for professional scientists to be constantly reviewing each other’s experiments. If experiments are repeated, it is usually because a conclusion has been reached that is outside the current paradigm. However, ideas and methods are critiqued before and during publication and acceptance. Ideas and methods are debated and shared in the workplace, at conferences and in scientific journals

Myth: Acceptance of new scientific knowledge is straightforward

The process of building knowledge in science is often portrayed as procedural, routine and unproblematic – leading unambiguously and inevitably to ‘proven science’. The way science investigations and findings are reported can reinforce this myth. However, it is impossible to make all observations relevant to a given situation, for all time – past, present and future – and there is always a creative leap from evidence to scientific knowledge. New interpretations for evidence are not automatically accepted by the scientific community.

A new idea that is not too far from the expectations of scientists working in a particular field would probably be accepted and published in scientific journals, but if the idea appears to be a significant breakthrough or is rather radical, its acceptance is by no means straightforward. Some examples of scientific ideas that were originally rejected because they fell outside the accepted paradigm include the Sun-centred solar system , the germ theory of disease and continental drift .

Myth: Science models ‘are real’

Models are just explanations of perceived representations of reality. A good example is the particle theory of matter , which pictures atoms and molecules as tiny discrete balls that have elastic collisions. This is a model that explains a whole range of phenomena, but no one has actually ever seen these tiny balls. The model is useful and it works as a means to explain and to predict a phenomenon.

Myth: A hypothesis is an educated guess

Everyday use of the word ‘hypothesis’ means an intelligent guess. For science, it can be misunderstood to mean an assumption made before doing an experiment or an idea not yet confirmed by an experiment. A better definition of a hypothesis in science is ‘a tentative explanation for a scientific problem, based on currently accepted scientific understanding and creative thinking’. Hypotheses are supported by lines of evidence and are based on the prior experience, background knowledge and observations of the scientists.

Myth: Hypotheses become theories that, in turn, become laws

Hypothesis, theory and law are three terms that are often confused. This myth says that facts and observations produce hypotheses, which give rise to theories, which, in turn, produce laws if sufficient evidence is amassed – so laws are theories that have been proved true.

Actually, hypotheses, theories and laws are as unalike as apples, oranges and bananas. They can’t grow into each other. Theories and laws are very different types of knowledge. Laws are generalisations, principles, relationships or patterns in nature that have been established by empirical data. Theories are explanations of those generalisations (also corroborated by empirical data).

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StatAnalytica

Step-by-step guide to hypothesis testing in statistics

hypothesis testing in statistics

Hypothesis testing in statistics helps us use data to make informed decisions. It starts with an assumption or guess about a group or population—something we believe might be true. We then collect sample data to check if there is enough evidence to support or reject that guess. This method is useful in many fields, like science, business, and healthcare, where decisions need to be based on facts.

Learning how to do hypothesis testing in statistics step-by-step can help you better understand data and make smarter choices, even when things are uncertain. This guide will take you through each step, from creating your hypothesis to making sense of the results, so you can see how it works in practical situations.

What is Hypothesis Testing?

Table of Contents

Hypothesis testing is a method for determining whether data supports a certain idea or assumption about a larger group. It starts by making a guess, like an average or a proportion, and then uses a small sample of data to see if that guess seems true or not.

For example, if a company wants to know if its new product is more popular than its old one, it can use hypothesis testing. They start with a statement like “The new product is not more popular than the old one” (this is the null hypothesis) and compare it with “The new product is more popular” (this is the alternative hypothesis). Then, they look at customer feedback to see if there’s enough evidence to reject the first statement and support the second one.

Simply put, hypothesis testing is a way to use data to help make decisions and understand what the data is really telling us, even when we don’t have all the answers.

Importance Of Hypothesis Testing In Decision-Making And Data Analysis

Hypothesis testing is important because it helps us make smart choices and understand data better. Here’s why it’s useful:

  • Reduces Guesswork : It helps us see if our guesses or ideas are likely correct, even when we don’t have all the details.
  • Uses Real Data : Instead of just guessing, it checks if our ideas match up with real data, which makes our decisions more reliable.
  • Avoids Errors : It helps us avoid mistakes by carefully checking if our ideas are right so we don’t make costly errors.
  • Shows What to Do Next : It tells us if our ideas work or not, helping us decide whether to keep, change, or drop something. For example, a company might test a new ad and decide what to do based on the results.
  • Confirms Research Findings : It makes sure that research results are accurate and not just random chance so that we can trust the findings.

Here’s a simple guide to understanding hypothesis testing, with an example:

1. Set Up Your Hypotheses

Explanation: Start by defining two statements:

  • Null Hypothesis (H0): This is the idea that there is no change or effect. It’s what you assume is true.
  • Alternative Hypothesis (H1): This is what you want to test. It suggests there is a change or effect.

Example: Suppose a company says their new batteries last an average of 500 hours. To check this:

  • Null Hypothesis (H0): The average battery life is 500 hours.
  • Alternative Hypothesis (H1): The average battery life is not 500 hours.

2. Choose the Test

Explanation: Pick a statistical test that fits your data and your hypotheses. Different tests are used for various kinds of data.

Example: Since you’re comparing the average battery life, you use a one-sample t-test .

3. Set the Significance Level

Explanation: Decide how much risk you’re willing to take if you make a wrong decision. This is called the significance level, often set at 0.05 or 5%.

Example: You choose a significance level of 0.05, meaning you’re okay with a 5% chance of being wrong.

4. Gather and Analyze Data

Explanation: Collect your data and perform the test. Calculate the test statistic to see how far your sample result is from what you assumed.

Example: You test 30 batteries and find they last an average of 485 hours. You then calculate how this average compares to the claimed 500 hours using the t-test.

5. Find the p-Value

Explanation: The p-value tells you the probability of getting a result as extreme as yours if the null hypothesis is true.

Example: You find a p-value of 0.0001. This means there’s a very small chance (0.01%) of getting an average battery life of 485 hours or less if the true average is 500 hours.

6. Make Your Decision

Explanation: Compare the p-value to your significance level. If the p-value is smaller, you reject the null hypothesis. If it’s larger, you do not reject it.

Example: Since 0.0001 is much less than 0.05, you reject the null hypothesis. This means the data suggests the average battery life is different from 500 hours.

7. Report Your Findings

Explanation: Summarize what the results mean. State whether you rejected the null hypothesis and what that implies.

Example: You conclude that the average battery life is likely different from 500 hours. This suggests the company’s claim might not be accurate.

Hypothesis testing is a way to use data to check if your guesses or assumptions are likely true. By following these steps—setting up your hypotheses, choosing the right test, deciding on a significance level, analyzing your data, finding the p-value, making a decision, and reporting results—you can determine if your data supports or challenges your initial idea.

Understanding Hypothesis Testing: A Simple Explanation

Hypothesis testing is a way to use data to make decisions. Here’s a straightforward guide:

1. What is the Null and Alternative Hypotheses?

  • Null Hypothesis (H0): This is your starting assumption. It says that nothing has changed or that there is no effect. It’s what you assume to be true until your data shows otherwise. Example: If a company says their batteries last 500 hours, the null hypothesis is: “The average battery life is 500 hours.” This means you think the claim is correct unless you find evidence to prove otherwise.
  • Alternative Hypothesis (H1): This is what you want to find out. It suggests that there is an effect or a difference. It’s what you are testing to see if it might be true. Example: To test the company’s claim, you might say: “The average battery life is not 500 hours.” This means you think the average battery life might be different from what the company says.

2. One-Tailed vs. Two-Tailed Tests

  • One-Tailed Test: This test checks for an effect in only one direction. You use it when you’re only interested in finding out if something is either more or less than a specific value. Example: If you think the battery lasts longer than 500 hours, you would use a one-tailed test to see if the battery life is significantly more than 500 hours.
  • Two-Tailed Test: This test checks for an effect in both directions. Use this when you want to see if something is different from a specific value, whether it’s more or less. Example: If you want to see if the battery life is different from 500 hours, whether it’s more or less, you would use a two-tailed test. This checks for any significant difference, regardless of the direction.

3. Common Misunderstandings

  • Clarification: Hypothesis testing doesn’t prove that the null hypothesis is true. It just helps you decide if you should reject it. If there isn’t enough evidence against it, you don’t reject it, but that doesn’t mean it’s definitely true.
  • Clarification: A small p-value shows that your data is unlikely if the null hypothesis is true. It suggests that the alternative hypothesis might be right, but it doesn’t prove the null hypothesis is false.
  • Clarification: The significance level (alpha) is a set threshold, like 0.05, that helps you decide how much risk you’re willing to take for making a wrong decision. It should be chosen carefully, not randomly.
  • Clarification: Hypothesis testing helps you make decisions based on data, but it doesn’t guarantee your results are correct. The quality of your data and the right choice of test affect how reliable your results are.

Benefits and Limitations of Hypothesis Testing

  • Clear Decisions: Hypothesis testing helps you make clear decisions based on data. It shows whether the evidence supports or goes against your initial idea.
  • Objective Analysis: It relies on data rather than personal opinions, so your decisions are based on facts rather than feelings.
  • Concrete Numbers: You get specific numbers, like p-values, to understand how strong the evidence is against your idea.
  • Control Risk: You can set a risk level (alpha level) to manage the chance of making an error, which helps avoid incorrect conclusions.
  • Widely Used: It can be used in many areas, from science and business to social studies and engineering, making it a versatile tool.

Limitations

  • Sample Size Matters: The results can be affected by the size of the sample. Small samples might give unreliable results, while large samples might find differences that aren’t meaningful in real life.
  • Risk of Misinterpretation: A small p-value means the results are unlikely if the null hypothesis is true, but it doesn’t show how important the effect is.
  • Needs Assumptions: Hypothesis testing requires certain conditions, like data being normally distributed . If these aren’t met, the results might not be accurate.
  • Simple Decisions: It often results in a basic yes or no decision without giving detailed information about the size or impact of the effect.
  • Can Be Misused: Sometimes, people misuse hypothesis testing, tweaking data to get a desired result or focusing only on whether the result is statistically significant.
  • No Absolute Proof: Hypothesis testing doesn’t prove that your hypothesis is true. It only helps you decide if there’s enough evidence to reject the null hypothesis, so the conclusions are based on likelihood, not certainty.

Final Thoughts 

Hypothesis testing helps you make decisions based on data. It involves setting up your initial idea, picking a significance level, doing the test, and looking at the results. By following these steps, you can make sure your conclusions are based on solid information, not just guesses.

This approach lets you see if the evidence supports or contradicts your initial idea, helping you make better decisions. But remember that hypothesis testing isn’t perfect. Things like sample size and assumptions can affect the results, so it’s important to be aware of these limitations.

In simple terms, using a step-by-step guide for hypothesis testing is a great way to better understand your data. Follow the steps carefully and keep in mind the method’s limits.

What is the difference between one-tailed and two-tailed tests?

 A one-tailed test assesses the probability of the observed data in one direction (either greater than or less than a certain value). In contrast, a two-tailed test looks at both directions (greater than and less than) to detect any significant deviation from the null hypothesis.

How do you choose the appropriate test for hypothesis testing?

The choice of test depends on the type of data you have and the hypotheses you are testing. Common tests include t-tests, chi-square tests, and ANOVA. You get more details about ANOVA, you may read Complete Details on What is ANOVA in Statistics ?  It’s important to match the test to the data characteristics and the research question.

What is the role of sample size in hypothesis testing?  

Sample size affects the reliability of hypothesis testing. Larger samples provide more reliable estimates and can detect smaller effects, while smaller samples may lead to less accurate results and reduced power.

Can hypothesis testing prove that a hypothesis is true?  

Hypothesis testing cannot prove that a hypothesis is true. It can only provide evidence to support or reject the null hypothesis. A result can indicate whether the data is consistent with the null hypothesis or not, but it does not prove the alternative hypothesis with certainty.

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Hypothesis vs. Theory

A hypothesis is either a suggested explanation for an observable phenomenon, or a reasoned prediction of a possible causal correlation among multiple phenomena. In science , a theory is a tested, well-substantiated, unifying explanation for a set of verified, proven factors. A theory is always backed by evidence; a hypothesis is only a suggested possible outcome, and is testable and falsifiable.

Comparison chart

Hypothesis versus Theory comparison chart
HypothesisTheory
Definition A suggested explanation for an observable phenomenon or prediction of a possible causal correlation among multiple phenomena. In , a theory is a well-substantiated, unifying explanation for a set of verified, proven hypotheses.
Based on Suggestion, possibility, projection or prediction, but the result is uncertain. Evidence, verification, repeated testing, wide scientific consensus
Testable Yes Yes
Falsifiable Yes Yes
Is well-substantiated? No Yes
Is well-tested? No Yes
Data Usually based on very limited data Based on a very wide set of data tested under various circumstances.
Instance Specific: Hypothesis is usually based on a very specific observation and is limited to that instance. General: A theory is the establishment of a general principle through multiple tests and experiments, and this principle may apply to various specific instances.
Purpose To present an uncertain possibility that can be explored further through experiments and observations. To explain why a large set of observations are consistently made.

Examples of Theory and Hypothesis

Theory: Einstein's theory of relativity is a theory because it has been tested and verified innumerable times, with results consistently verifying Einstein's conclusion. However, simply because Einstein's conclusion has become a theory does not mean testing of this theory has stopped; all science is ongoing. See also the Big Bang theory , germ theory , and climate change .

Hypothesis: One might think that a prisoner who learns a work skill while in prison will be less likely to commit a crime when released. This is a hypothesis, an "educated guess." The scientific method can be used to test this hypothesis, to either prove it is false or prove that it warrants further study. (Note: Simply because a hypothesis is not found to be false does not mean it is true all or even most of the time. If it is consistently true after considerable time and research, it may be on its way to becoming a theory.)

This video further explains the difference between a theory and a hypothesis:

Common Misconception

People often tend to say "theory" when what they're actually talking about is a hypothesis. For instance, "Migraines are caused by drinking coffee after 2 p.m. — well, it's just a theory, not a rule."

This is actually a logically reasoned proposal based on an observation — say 2 instances of drinking coffee after 2 p.m. caused a migraine — but even if this were true, the migraine could have actually been caused by some other factors.

Because this observation is merely a reasoned possibility, it is testable and can be falsified — which makes it a hypothesis, not a theory.

  • What is a Scientific Hypothesis? - LiveScience
  • Wikipedia:Scientific theory

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Comments: Hypothesis vs Theory

Anonymous comments (2).

October 11, 2013, 1:11pm "In science, a theory is a well-substantiated, unifying explanation for a set of verified, proven hypotheses." But there's no such thing as "proven hypotheses". Hypotheses can be tested/falsified, they can't be "proven". That's just not how science works. Logical deductions based on axioms can be proven, but not scientific hypotheses. On top of that I find it somewhat strange to claim that a theory doesn't have to be testable, if it's built up from hypotheses, which DO have to be testable... — 80.✗.✗.139
May 6, 2014, 11:45pm "Evolution is a theory, not a fact, regarding the origin of living things." this statement is poorly formed because it implies that a thing is a theory until it gets proven and then it is somehow promoted to fact. this is just a misunderstanding of what the words mean, and of how science progresses generally. to say that a theory is inherently dubious because "it isn't a fact" is pretty much a meaningless statement. no expression which qualified as a mere fact could do a very good job of explaining the complicated process by which species have arisen on Earth over the last billion years. in fact, if you claimed that you could come up with such a single fact, now THAT would be dubious! everything we observe in nature supports the theory of evolution, and nothing we observe contradicts it. when you can say this about a theory, it's a pretty fair bet that the theory is correct. — 71.✗.✗.151
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  1. And now you are ready to make an educated guess

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  4. Hypothesis A Hypothesis is an educated guess of

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  5. Remember a hypothesis is an educated guess that predicts the outcome of

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VIDEO

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  1. What is a scientific hypothesis?

    What is a scientific hypothesis?

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    Hypothesis - Wikipedia ... Hypothesis

  3. What is a Hypothesis

    Definition: Hypothesis is an educated guess or proposed explanation for a phenomenon, based on some initial observations or data. It is a tentative statement that can be tested and potentially proven or disproven through further investigation and experimentation. Hypothesis is often used in scientific research to guide the design of experiments ...

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  9. What Are the Elements of a Good Hypothesis?

    A hypothesis is an educated guess or prediction of what will happen in a scientific experiment. Learn the elements of a good hypothesis, such as cause and effect, variables, and null hypothesis, with examples.

  10. The hypothesis: An educated guess

    The hypothesis: An educated guess. Susan B Shipley, RN The hypothesis: An educated guess The purpose of research or scientific in- quiry is to determine how variables are related. We do not test variables; we test the relationship between them. A re- searcher’s prediction of how the vari- ables relate to each other is called the hypothesis.

  11. Facts, Hypotheses, Theories, and Laws: What's the Difference?

    A hypothesis is basically an educated guess. It's a possible explanation that hasn't yet achieved the certainty of a theory. There may be experimental support behind it, but not on the level that a theory has. It is, however, entirely possible for a hypothesis to become a theory once enough evidence has been accumulated. Laws

  12. Scientific Hypothesis Examples

    A hypothesis is an educated guess about what you think will happen in a scientific experiment, based on your observations. Before conducting the experiment, you propose a hypothesis so that you can determine if your prediction is supported.

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  14. PDF IS NOT an educated guess. It is an un testable

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    Merriam Webster defines a hypothesis as "an assumption or concession made for the sake of argument.". In other words, a hypothesis is an educated guess. Scientists make a reasonable assumption--or a hypothesis--then design an experiment to test whether it's true or not.

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  17. A hypothesis can't be right unless it can be proven wrong

    A hypothesis is the cornerstone of the scientific method. It is an educated guess about how the world works that integrates knowledge with observation. Everyone appreciates that a hypothesis must be testable to have any value, but there is a much stronger requirement that a hypothesis must meet.

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  21. Step-by-step guide to hypothesis testing in statistics

    Hypothesis testing is a method for determining whether data supports a certain idea or assumption about a larger group. It starts by making a guess, like an average or a proportion, and then uses a small sample of data to see if that guess seems true or not.

  22. Theory vs. Hypothesis: Basics of the Scientific Method

    Level Up Your Team. See why leading organizations rely on MasterClass for learning & development. Though you may hear the terms "theory" and "hypothesis" used interchangeably, these two scientific terms have drastically different meanings in the world of science.

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