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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!

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.

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.  

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. 

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. 

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?

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 ).

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.

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

Ashley Sufflé Robinson has a Ph.D. in 19th Century English Literature. As a content writer for PrepScholar, Ashley is passionate about giving college-bound students the in-depth information they need to get into the school of their dreams.

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• How to Write a Strong Hypothesis | Guide & Examples

How to Write a Strong Hypothesis | Guide & Examples

Published on 6 May 2022 by Shona McCombes .

A hypothesis is a statement that can be tested by scientific research. If you want to test a relationship between two or more variables, you need to write hypotheses before you start your experiment or data collection.

Table of contents

What is a hypothesis, developing a hypothesis (with example), hypothesis examples, frequently asked questions about writing hypotheses.

A hypothesis states your predictions about what your research will find. It is a tentative answer to your research question that has not yet been tested. For some research projects, you might have to write several hypotheses that address different aspects of your research question.

A hypothesis is not just a guess – it should be based on existing theories and knowledge. It also has to be testable, which means you can support or refute it through scientific research methods (such as experiments, observations, and statistical analysis of data).

Variables in hypotheses

Hypotheses propose a relationship between two or more variables . An independent variable is something the researcher changes or controls. A dependent variable is something the researcher observes and measures.

In this example, the independent variable is exposure to the sun – the assumed cause . The dependent variable is the level of happiness – the assumed effect .

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Step 1: ask a question.

Writing a hypothesis begins with a research question that you want to answer. The question should be focused, specific, and researchable within the constraints of your project.

Step 2: Do some preliminary research

Your initial answer to the question should be based on what is already known about the topic. Look for theories and previous studies to help you form educated assumptions about what your research will find.

At this stage, you might construct a conceptual framework to identify which variables you will study and what you think the relationships are between them. Sometimes, you’ll have to operationalise more complex constructs.

Step 3: Formulate your hypothesis

Now you should have some idea of what you expect to find. Write your initial answer to the question in a clear, concise sentence.

Step 4: Refine your hypothesis

You need to make sure your hypothesis is specific and testable. There are various ways of phrasing a hypothesis, but all the terms you use should have clear definitions, and the hypothesis should contain:

• The relevant variables
• The specific group being studied
• The predicted outcome of the experiment or analysis

Step 5: Phrase your hypothesis in three ways

To identify the variables, you can write a simple prediction in if … then form. The first part of the sentence states the independent variable and the second part states the dependent variable.

In academic research, hypotheses are more commonly phrased in terms of correlations or effects, where you directly state the predicted relationship between variables.

If you are comparing two groups, the hypothesis can state what difference you expect to find between them.

Step 6. Write a null hypothesis

If your research involves statistical hypothesis testing , you will also have to write a null hypothesis. The null hypothesis is the default position that there is no association between the variables. The null hypothesis is written as H 0 , while the alternative hypothesis is H 1 or H a .

Hypothesis testing is a formal procedure for investigating our ideas about the world using statistics. It is used by scientists to test specific predictions, called hypotheses , by calculating how likely it is that a pattern or relationship between variables could have arisen by chance.

A hypothesis is not just a guess. It should be based on existing theories and knowledge. It also has to be testable, which means you can support or refute it through scientific research methods (such as experiments, observations, and statistical analysis of data).

A research hypothesis is your proposed answer to your research question. The research hypothesis usually includes an explanation (‘ x affects y because …’).

A statistical hypothesis, on the other hand, is a mathematical statement about a population parameter. Statistical hypotheses always come in pairs: the null and alternative hypotheses. In a well-designed study , the statistical hypotheses correspond logically to the research hypothesis.

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Definition of hypothesis

Did you know.

The Difference Between Hypothesis and Theory

A hypothesis is an assumption, an idea that is proposed for the sake of argument so that it can be tested to see if it might be true.

In the scientific method, the hypothesis is constructed before any applicable research has been done, apart from a basic background review. You ask a question, read up on what has been studied before, and then form a hypothesis.

A hypothesis is usually tentative; it's an assumption or suggestion made strictly for the objective of being tested.

A theory , in contrast, is a principle that has been formed as an attempt to explain things that have already been substantiated by data. It is used in the names of a number of principles accepted in the scientific community, such as the Big Bang Theory . Because of the rigors of experimentation and control, it is understood to be more likely to be true than a hypothesis is.

In non-scientific use, however, hypothesis and theory are often used interchangeably to mean simply an idea, speculation, or hunch, with theory being the more common choice.

Since this casual use does away with the distinctions upheld by the scientific community, hypothesis and theory are prone to being wrongly interpreted even when they are encountered in scientific contexts—or at least, contexts that allude to scientific study without making the critical distinction that scientists employ when weighing hypotheses and theories.

The most common occurrence is when theory is interpreted—and sometimes even gleefully seized upon—to mean something having less truth value than other scientific principles. (The word law applies to principles so firmly established that they are almost never questioned, such as the law of gravity.)

This mistake is one of projection: since we use theory in general to mean something lightly speculated, then it's implied that scientists must be talking about the same level of uncertainty when they use theory to refer to their well-tested and reasoned principles.

The distinction has come to the forefront particularly on occasions when the content of science curricula in schools has been challenged—notably, when a school board in Georgia put stickers on textbooks stating that evolution was "a theory, not a fact, regarding the origin of living things." As Kenneth R. Miller, a cell biologist at Brown University, has said , a theory "doesn’t mean a hunch or a guess. A theory is a system of explanations that ties together a whole bunch of facts. It not only explains those facts, but predicts what you ought to find from other observations and experiments.”

While theories are never completely infallible, they form the basis of scientific reasoning because, as Miller said "to the best of our ability, we’ve tested them, and they’ve held up."

• proposition
• supposition

hypothesis , theory , law mean a formula derived by inference from scientific data that explains a principle operating in nature.

hypothesis implies insufficient evidence to provide more than a tentative explanation.

theory implies a greater range of evidence and greater likelihood of truth.

law implies a statement of order and relation in nature that has been found to be invariable under the same conditions.

Examples of hypothesis in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'hypothesis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Greek, from hypotithenai to put under, suppose, from hypo- + tithenai to put — more at do

1641, in the meaning defined at sense 1a

Phrases Containing hypothesis

• counter - hypothesis
• nebular hypothesis
• null hypothesis
• planetesimal hypothesis
• Whorfian hypothesis

Articles Related to hypothesis

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This is the Difference Between a Hypothesis and a Theory

In scientific reasoning, they're two completely different things

Dictionary Entries Near hypothesis

hypothermia

hypothesize

Cite this Entry

“Hypothesis.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/hypothesis. Accessed 2 May. 2024.

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A hypothesis is an explanation for a set of observations. Here are examples of a scientific hypothesis.

Although you could state a scientific hypothesis in various ways, most hypotheses are either "If, then" statements or forms of the null hypothesis . The null hypothesis is sometimes called the "no difference" hypothesis. The null hypothesis is good for experimentation because it's simple to disprove. If you disprove a null hypothesis, that is evidence for a relationship between the variables you are examining.

Examples of Null Hypotheses

• Hyperactivity is unrelated to eating sugar.
• All daisies have the same number of petals.
• The number of pets in a household is unrelated to the number of people living in it.
• A person's preference for a shirt is unrelated to its color.

Examples of If, Then Hypotheses

• If you get at least 6 hours of sleep, you will do better on tests than if you get less sleep.
• If you drop a ball, it will fall toward the ground.
• If you drink coffee before going to bed, then it will take longer to fall asleep.
• If you cover a wound with a bandage, then it will heal with less scarring.

Improving a Hypothesis to Make It Testable

You may wish to revise your first hypothesis in order to make it easier to design an experiment to test. For example, let's say you have a bad breakout the morning after eating a lot of greasy food. You may wonder if there is a correlation between eating greasy food and getting pimples. You propose the hypothesis:

Eating greasy food causes pimples.

Next, you need to design an experiment to test this hypothesis. Let's say you decide to eat greasy food every day for a week and record the effect on your face. Then, as a control, you'll avoid greasy food for the next week and see what happens. Now, this is not a good experiment because it does not take into account other factors such as hormone levels, stress, sun exposure, exercise, or any number of other variables that might conceivably affect your skin.

The problem is that you cannot assign cause to your effect . If you eat french fries for a week and suffer a breakout, can you definitely say it was the grease in the food that caused it? Maybe it was the salt. Maybe it was the potato. Maybe it was unrelated to diet. You can't prove your hypothesis. It's much easier to disprove a hypothesis.

So, let's restate the hypothesis to make it easier to evaluate the data:

Getting pimples is unaffected by eating greasy food.

So, if you eat fatty food every day for a week and suffer breakouts and then don't break out the week that you avoid greasy food, you can be pretty sure something is up. Can you disprove the hypothesis? Probably not, since it is so hard to assign cause and effect. However, you can make a strong case that there is some relationship between diet and acne.

If your skin stays clear for the entire test, you may decide to accept your hypothesis . Again, you didn't prove or disprove anything, which is fine

• Null Hypothesis Definition and Examples
• What Is a Hypothesis? (Science)
• What Are the Elements of a Good Hypothesis?
• Understanding Simple vs Controlled Experiments
• What Is a Testable Hypothesis?
• What 'Fail to Reject' Means in a Hypothesis Test
• Null Hypothesis Examples
• How To Design a Science Fair Experiment
• Scientific Method Vocabulary Terms
• Scientific Hypothesis Examples
• Six Steps of the Scientific Method
• An Example of a Hypothesis Test
• Definition of a Hypothesis
• Scientific Method Flow Chart
• Null Hypothesis and Alternative Hypothesis

HYPOTHESIS in a Sentence Examples: 21 Ways to Use Hypothesis

Have you ever wondered what a “hypothesis” is and how it fits into the scientific method? A hypothesis is a proposed explanation or educated guess that can be tested through research and experimentation to determine its validity.

In scientific inquiry, a hypothesis serves as the foundation for the study, guiding the direction of the research and helping to form conclusions based on the results. By formulating clear hypotheses, researchers can systematically investigate phenomena and gather evidence to support their claims.

Table of Contents

7 Examples Of Hypothesis Used In a Sentence For Kids

• Hypothesis is a guess we can test.
• We can make a hypothesis about what will happen.
• Our hypothesis will help us learn new things.
• Let’s think of a hypothesis to investigate.
• We can use our hypothesis to solve a problem.
• A good hypothesis can help us understand the world.
• Remember, our hypothesis is just a starting point.

14 Sentences with Hypothesis Examples

• Hypothesis : Students who study for at least 3 hours every day are likely to perform better in their exams.
• It is important for college students to form a hypothesis before conducting any research project.
• Hypothesis : Attending lectures regularly can significantly improve academic performance.
• College students can test their hypothesis through interactive experiments and surveys.
• Hypothesis : Using different study methods can have varied effects on information retention.
• It is necessary for students to critically analyze data to support or reject their hypothesis .
• Hypothesis : Students who engage in extracurricular activities may have a better overall college experience.
• In a scientific study, researchers must clearly define their hypothesis before proceeding with the experiment.
• Hypothesis : Regular exercise can positively impact a student’s mental health and academic performance.
• It is crucial for college students to document their hypothesis and research findings accurately.
• Hypothesis : Students who limit their social media usage may experience improved focus and productivity.
• College projects often require students to brainstorm and formulate a solid hypothesis .
• It is common for students to revise their hypothesis based on new information or research outcomes.
• Hypothesis : Implementing study breaks can enhance retention and understanding of complex subjects.

How To Use Hypothesis in Sentences?

Hypothesis is an educated guess or prediction that can be tested through observation or experimentation. When incorporating this term into a sentence, it is important to clearly identify it so readers can understand its significance.

Here are some tips on how to use hypothesis effectively in a sentence:

Clearly state your hypothesis in a simple and concise manner. For example, “The scientist’s hypothesis is that plants will grow faster with added sunlight.”

Use the word hypothesis to introduce your prediction or expectation before testing it. For instance, “Our hypothesis is that students who study regularly will perform better on the exam.”

Make sure to refer back to your hypothesis when discussing the results of your experiment. For example, “The data supported our initial hypothesis that exercise leads to improved cardiovascular health.”

You can also use the word hypothesis when comparing multiple predictions. For instance, “There are several hypotheses about the cause of the mysterious illness, but more research is needed to determine the correct one.”

By following these guidelines, you can effectively incorporate hypothesis into your writing to communicate your predictions or expectations clearly and accurately.

In conclusion, sentences with the keyword “hypothesis” often express a proposed explanation or prediction that can be tested through research or observation. These sentences play a crucial role in scientific inquiry by guiding investigations and exploring relationships between variables. For example, “The researchers formulated a hypothesis to predict the effect of sunlight on plant growth” demonstrates how hypotheses are used to frame a study’s objectives and outcomes.

Clear and concise sentences with hypotheses are essential for building a solid foundation for scientific exploration and discovery. They provide a starting point for experiments, helping researchers to structure their methodologies and draw meaningful conclusions. By carefully crafting hypotheses, scientists can effectively test their theories, gather evidence, and contribute to the advancement of knowledge in various fields.

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Examples of “Hypothesis” In A Sentence

The hypothesis is a very important part of doing science and thinking carefully. It is like the strong supporting structure of a building for the process of research. A hypothesis is a clever guess or idea that can be tested to see if it is true or not. It helps us understand things or predict what might happen. In this article, we will look at many examples of ‘hypothesis’ in sentences .

Table of Contents

Sentences with Hypothesis

• Hypothesis : The sun rises in the east.
• They formulated a null hypothesis to compare against the alternative.
• We need to revise the original hypothesis .
• They discussed the hypothesis with colleagues in their field.
• They formulated competing hypotheses to compare and contrast the findings.
• The students generated multiple hypotheses for their investigation.
• The hypothesis was generated from observations.
• The hypothesis is the starting point of scientific investigation.
• The researchers tested the hypothesis using various methodologies.
• We need to investigate the hypothesis
• The hypothesis needs more evidence to be proven.
• The hypothesis was rejected due to flaws in the experimental design.
• They tested the hypothesis using computer simulations.
• The team tested the hypothesis using advanced technology.
• The hypothesis was derived from logical reasoning.
• They conducted surveys to gather data for their hypotheses .
• They proposed alternative hypotheses for further exploration.
• The hypothesis was consistent with data from other studies.
• The hypothesis was based on logical reasoning.
• The hypothesis was supported by the statistical analysis.

Sentences with “Hypothesis”

• The hypothesis was proven incorrect.
• The hypothesis was rejected due to lack of evidence.
• They discussed the hypothesis with their peers.
• The hypothesis was proposed based on logical deductions.
• The hypothesis was validated through rigorous peer review.
• The team discussed potential hypotheses during brainstorming sessions.
• They discussed the limitations of their hypothesis
• The students proposed various hypotheses for the investigation.
• The hypothesis was confirmed by independent replication studies.
• The students formed testable hypotheses for their projects.
• They used a control group to test their hypothesis .
• The hypothesis was formulated as a cause-and-effect relationship.
• The hypothesis was supported by the literature review.
• Scientists test their hypotheses through experiments.
• The hypothesis was proposed based on observations in nature.
• They analyzed the data to validate the hypothesis .
• They designed the experiment to test the hypothesis
• The hypothesis was based on previous research findings.
• They revised the hypothesis based on constructive feedback.
• They presented their hypotheses at a research symposium.
• They conducted experiments to test their hypotheses .
• The hypothesis was supported by a large and diverse sample.
• The researchers tested the hypothesis using a variety of methodologies.
• They conducted surveys to gather data that supported their hypothesis .
• The team formulated new hypotheses for future investigations.
• The hypothesis was consistent with experimental results.

“Hypothesis” Use in Sentence

• They discussed the implications of the hypothesis on their field.
• The researchers discussed the implications of their hypotheses .
• The hypothesis was derived from careful observation and analysis.
• The team developed alternative hypotheses for further investigation.
• They presented their hypotheses to the research community.
• The hypothesis was based on a comprehensive review of the literature.
• The hypothesis was supported by strong logical reasoning.
• They discussed the implications of their hypothesis for future research.
• The hypothesis was based on a well-established scientific theory.
• The researchers tested their hypotheses using different methodologies.
• The hypothesis was supported by empirical evidence.
• The researchers evaluated their hypotheses
• The hypothesis was disproven by contradictory evidence.
• The researchers discussed the limitations of their hypotheses .
• The hypothesis was based on a well-established theory.
• The hypothesis was supported by a large sample size.
• The hypothesis was consistent with patterns observed in nature.
• They proposed new hypotheses for future investigation.
• The hypothesis was confirmed by the results of the study.
• The hypothesis guided the research process.
• The hypothesis was supported by strong scientific consensus.
• The hypothesis was rejected due to methodological limitations.
• The researchers proposed several hypotheses to explain the phenomenon.
• The hypothesis was confirmed by multiple researchers in the field.
• The hypothesis was validated through multiple studies.

Sentences Using “Hypothesis”

• The researchers conducted experiments to test their hypotheses .
• The hypothesis was based on observations from nature.
• The hypothesis was supported by a wide range of evidence.
• They formed competing hypotheses to compare.
• Scientists often revise their hypotheses based on new data.
• They conducted experiments to support their hypotheses .
• The team discussed their hypothesis during the meeting.
• The students discussed their hypotheses in class.
• They developed a new hypothesis based on recent findings.
• They discussed the hypothesis with other experts in the field.
• The hypothesis was supported by a significant p-value.
• The hypothesis was generated from real-world observations.
• Mary’s hypothesis was supported by the data.
• They tested their hypotheses across different populations.
• The researchers tested multiple hypotheses to find the answer.
• They presented their hypothesis at a scientific conference.
• The hypothesis was supported by strong evidence.
• They presented their hypotheses in a clear and concise manner.
• The researchers proposed a working hypothesis to start their study.
• The team discussed the hypothesis during the brainstorming session.
• The researchers proposed different hypotheses for the observed behavior.
• The hypothesis is a crucial part of any scientific study.
• The hypothesis was refuted by the experimental results.

“Hypothesis” Sentences Examples

• We need to gather more data to test the hypothesis .
• The hypothesis was consistent with existing theories.
• The hypothesis was supported by a strong theoretical framework.
• The hypothesis was based on previous studies.
• They formulated a null hypothesis as the default assumption.
• The hypothesis was consistent with theoretical predictions.
• The hypothesis was based on prior knowledge.
• The hypothesis was supported by strong experimental data.
• The team formed a new hypothesis after analyzing the data.
• The hypothesis was consistent with the findings of previous studies.
• The hypothesis was rejected due to methodological flaws.
• The hypothesis was proven right after extensive testing.
• The hypothesis was consistent with real-world observations.
• The team tested their hypothesis in different conditions.
• The hypothesis was consistent with the predictions.
• The students generated their hypotheses for the experiment.
• The hypothesis was confirmed by multiple independent studies.
• The hypothesis was tested using a randomized controlled trial.
• They formulated a null hypothesis to compare against.
• The hypothesis was based on inductive reasoning.
• The hypothesis was validated through repeated experiments.
• The hypothesis guided the design of the experiment.
• They used statistical analysis to validate the hypothesis .
• The researchers discussed the implications of their hypothesis on society.
• They revised the hypothesis based on feedback from experts.
• The hypothesis was confirmed by expert analysis.
• Hypotheses are essential in the scientific method.
• Lisa proposed an interesting hypothesis for her project.
• They analyzed the data to support their hypothesis .
• The hypothesis was supported by compelling arguments.
• They conducted interviews to explore their hypotheses .

Use “Hypothesis” In A Sentence

• Sarah formulated a new hypothesis for her research.
• The hypothesis was confirmed by the experiment.
• The hypothesis was generated from prior observations.
• They conducted surveys to test their hypotheses .
• The hypothesis was supported by well-documented experimental results.
• The hypothesis was supported by strong correlations.
• The hypothesis was proposed after reviewing the literature.
• They proposed a working hypothesis to guide their study.
• The hypothesis was consistent with the observed results.
• They proposed alternative hypotheses for future exploration.
• The hypothesis was validated through rigorous statistical methods.
• The researchers tested their hypotheses
• John’s hypothesis led to groundbreaking discoveries.
• The hypothesis was supported by statistical significance.
• The researchers formulated a null hypothesis to compare against.
• The hypothesis was supported by theoretical predictions.
• They formed competing hypotheses to compare and contrast.
• The hypothesis was consistent with historical data.
• The hypothesis was supported by multiple lines of evidence.
• The hypothesis was revised based on feedback from reviewers.
• The scientists formulated a specific hypothesis to test.
• The hypothesis was based on empirical data.

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Hypothesis in a Sentence  🔊

Definition of Hypothesis

a proposed explanation or theory that is studied through scientific testing

Examples of Hypothesis in a sentence

The scientist’s hypothesis did not stand up, since research data was inconsistent with his guess.  🔊

Each student gave a hypothesis and theorized which plant would grow the tallest during the study.  🔊

A hypothesis was presented by the panel, giving a likely explanation for why the trial medicine didn’t seem to have much of an effect on the patients.  🔊

During the study, the researcher changed her hypothesis to a new assumption that fit with current data.  🔊

To confirm his hypothesis on why the dolphin wasn’t eating, the marine biologists did several tests over a week’s time.  🔊

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The Horrible Truth About Shaken Baby Syndrome Cases

About 20 years ago, at the beginning of my prison stint, I was double-bunked with a fella who was in for shaking a baby to death. When you’re locked in a cell with a guy, there’s an initial bonding phase. You do pushups together. You talk about your past lives. My story ended with what led me to prison. I was a drug dealer. Shot and killed a man in Brooklyn. My bunkie wasn’t criminal—he was a square. He never mentioned his crime. So, I asked. He hadn’t shaken his girlfriend’s baby to death, he told me, and the science behind “shaken baby syndrome,” the theory that violent shaking causes fatal brain injuries, was unreliable.

I didn’t believe him. I just figured he couldn’t admit to killing a kid. As you can imagine, baby killers don’t do well in prison. I figured experts wouldn’t testify to things they were uncertain about. I think most people, including jurors, figure that. I began to question this in 2022, when I started working with Yale Law School’s Prison Letters Project , an initiative that responds to letters we receive from prisoners telling us about injustices. I noticed that many of these letter writers claimed that they had been wrongfully convicted under the SBS theory.

“I was facing allegations of child abuse and first-degree murder of my 5-month-old son,” Tom Imschweiler wrote to PLP from a North Carolina prison. He explained that his case was like others “sent to prison based on the hypothesis of shaken baby syndrome. What sets me apart is the support of professionals in the field and the unwavering dedication my family and friends have for me.”

In July 2018, Tom, a 31-year-old landscaper, and his 29-year-old girlfriend, Laura Michael, who worked in finance, took their 5-month-old son Franklin on a trip from their home in Harrisburg, Pennsylvania, to the Outer Banks in North Carolina. A week earlier, Franklin had been sick, running a 104-degree fever, but his doctor signed off on the trip. Laura’s mother, sister, and brother-in law drove down too. They all rented a beach house.

In the middle of the night, Franklin started whimpering. Tom woke up and carried his son to the living room. He propped Franklin between two pillows on the couch, he says, while he went to the kitchen to warm a bottle of formula. “Minutes later, I returned and found him facedown in the pillow,” Tom later wrote.

Tom yelled for help, and the whole family woke up, frantic. Tom and his brother-in-law, a medic, did CPR. Laura called for an ambulance. Franklin was rushed to the hospital, where he died days later. Doctors discovered a triad of internal symptoms—subdural and retinal hemorrhage and brain swelling—that some doctors say can be explained only by shaken baby syndrome, a diagnosis that criminally implicates the child’s last caregiver as an abuser. Soon after Franklin’s death, Tom was arrested and charged with murder for killing his baby. He is now in prison after taking a plea deal that significantly reduced the possible sentence, though he has not admitted guilt and maintains his innocence.

Tom’s story is not unusual. For nearly two decades, shaken baby syndrome has divided the medical community. Some doctors believe that the triad of symptoms used for the diagnosis cannot be explained by a fall or an accident. Others say that there can be alternate explanations—including accidental suffocation, underlying illnesses, viral infections, or bleeding disorders.

The result is a split screen of legal rulings in cases like Tom’s. Back in 2008, the Wisconsin Court of Appeals became the first to overturn an SBS conviction, writing that there was “fierce disagreement” among doctors and “a shift in mainstream medical opinion” about the certainty of the diagnosis. Last year, a New Jersey appeals court barred the admission of evidence about shaken baby syndrome, calling it “junk science.” Yet elsewhere, hundreds of parents and caregivers continue to be prosecuted based on the same medical theory. A review of more than 1,400 appellate rulings between 2008 and 2018 found that only 3 percent of SBS convictions were overturned, a far lower rate than in other types of cases.

The reality is that in parts of the country, evidence of the telltale triad of symptoms won’t warrant an arrest—but in other parts, it can literally amount to a death sentence.

This is the case for 56-year-old Robert Roberson. He is on death row in Texas for an SBS conviction. In 2002 he carried his 2-year-old daughter, Nikki Curtis, limp and blue, into an East Texas hospital. She died the next day. After doctors diagnosed shaken baby syndrome, Roberson was arrested. The detective who questioned him, Brian Wharton, noted his lack of emotion—Roberson didn’t seem defensive, angry, or sad. In 2003 a jury convicted Roberson and sentenced him to death.

The jury didn’t know that Roberson would later receive a diagnosis for autism, which could explain his low affect. The jurors also did not learn that Nikki had suffered from chronic illness since birth. Days before she died, she had bouts of breathing apnea from undiagnosed pneumonia. She was also taking an opioid, for an unspecified respiratory illness, a treatment that can cause breathing problems. In 2018, when Roberson’s attorney, Gretchen Sween, told Wharton about Roberson’s autism and the other information about Nikki’s health, it was clear to her the detective had long been troubled by the case. Wharton agreed to testify about his initial misgivings and about how Roberson’s autism could have influenced his opinion about Roberson during the investigation.

But neither the evidence about Nikki’s health nor Wharton’s testimony made a difference. In spite of these developments, the Texas courts have denied Roberson relief, and last year the Supreme Court refused to hear the case. Roberson could receive an execution date any day now.

Doctors who defend the science behind SBS convictions point out that abusive head trauma , a term that includes shaken baby syndrome, is the third leading cause of head injury in children. They say health care providers conduct extensive evaluations before reaching a diagnosis. Robert Sege, a professor at Tufts University School of Medicine who has served on the American Academy of Pediatrics’ Committee on Child Abuse and Neglect, acknowledges that wrongful convictions occur. But he says he’s not sure how that fact “has any relevance to the issue of abusive head trauma.”

“As a doctor and experienced child abuse pediatrician, I know that abusive head trauma exists,” Sege said. “I have cared for injured children, some of whom died. I have met with their parents, who were deep in misery as the realization of what they had done seeped in.”

In some cases, prosecutors rely in part on medical evidence, separate from the SBS diagnosis, which they say points to a history of child abuse. In Franklin’s case, there was no known history of abuse, but doctors found that he had fractured ribs and a rectal tear. Tom and Laura had nonviolent explanations for those injuries. Franklin had been in a car accident months before his death, they said, which could have caused the fractures, and his temperature was taken anally while he had the high fever, soon before he died, which could account for the rectal tearing.

But the district attorney, Andrew Womble, had what he considered to be an admission of guilt. After his arrest in 2018, Tom wrote a letter to Laura from jail, which prosecutors intercepted and read. “Maybe the devil took my hand,” he wrote. “Maybe I did hurt my son.”

Tom now says he wrote the letter in a state of “absolute despair, believing that I somehow was responsible because that is all I was told from the moment I went into custody.” His defense attorney sent Franklin’s medical file to Mary Gilliland, a forensic pathologist and expert in abusive head trauma who has worked with North Carolina prosecutors for decades. Reviewing the case without payment, Gilliland concluded that Franklin’s death had been an accidental suffocation. His parents’ explanations for Franklin’s other injuries made sense to her too. “The age of the broken rib is just right for that time frame,” she said in a video presentation of her findings that prosecutors reviewed with the charges against Tom pending. “This is an older injury, and it’s unrelated.”

Womble did not drop the charges against Tom, but he offered an unusual plea deal for the alleged murder of a child: a five-year prison sentence for voluntary manslaughter.

In November 2021, Laura married Tom, who was out on bail, in a Pennsylvania courthouse. She was six months pregnant with their second child. Ten days later, they went to North Carolina, and Tom took what’s called an Alford plea, which allowed him to plead guilty to Franklin’s manslaughter while maintaining his innocence.

In a letter from prison, Tom said he took the plea “so my daughter will have her daddy before she’s old enough to have lifelong memories.” In the meantime, Laura is raising their child alone. She has posted an online petition asking North Carolina Gov. Roy Cooper to commute Tom’s sentence.

Tom lives in a dorm in Sanford Correctional Center, a low-security prison in rural North Carolina. He works off-grounds in a warehouse for $16.84 a week. Laura makes the 10-hour trip from Pennsylvania to North Carolina only a few times a year. She brings their new baby, who, Laura told me, beams when she sees her father in the visiting area. I thought about my old bunkie, the square with the SBS case, and I wondered about the pecking order part of prison, if other prisoners ostracized and judged Tom like I did my bunkie. I wondered if my bunkie really was innocent. I wondered if the knock-around guys who lived in his dorm called him a baby killer behind his back.

In the beginning, there were some guys who said things, Laura told me, but Tom has found a sense of security with others. They work, lift weights, talk about freedom. But I imagine he hasn’t shared everything with Laura. He has internalized plenty. It’s all we can do in here. What struck me about Tom and Laura was how the loss of their son, for which they were the most affected, was shadowed by this idea of justice. I asked Laura about that.

“I would want justice if my son was abused,” Laura told me. Her dog barked; her 2-year-old cried for her attention. “But he wasn’t. This was an injustice.”