How to write a hypothesis

A hypothesis is nothing more than a verifiable statement to find an answer to a specific question; A formalized hypothesis forces you to think about what results to expect in an experiment. 

Therefore, a hypothesis can be used for almost everything, such as testing different results in everyday tasks, identifying a possible ending in an investigation, forming the basis of a scientific experiment, etc.

In this article, you’ll learn the reasoning behind it, the different types of hypotheses, as well as how to write a hypothesis more clearly.

What is a hypothesis?

A hypothesis is a method of forecasting, an attempt to find an answer to something that has not yet been proven, an idea or a proposal based on limited evidence. 

In most cases, it is about proposing relationships between two (or more) variables: the independent variable (the change made) and the dependent variable (the measure). For example, suppose you are used to studying all night before an exam, but you are always too tired to understand the subject clearly, which causes you to get bad grades.

Therefore, the hypothesis is that if you study during the day, you will understand the subject and, consequently, you will get a good grade. In this example, the independent variable is the study time and the dependent variables are the understanding of the subject and the grade. 

As you can see, a hypothesis can be used in almost any situation, but it is most commonly to find it in research papers or scientific experiments. 

When writing a hypothesis, it is essential to be careful and thorough before starting to write it down. Since any hypothesis must be proven by facts, direct evidence and data evidence, even small flaws or misunderstandings in the construction of the hypothesis can have a negative impact on the quality of your research and its subsequent results. 

Types of research hypotheses and examples

There are several types of hypotheses depending on the nature or purpose of your hypothesis, whether it is for research or a scientific experiment. 

Before we get into how to write a hypothesis If there is no security system, let’s go over the different types to see which one is the most suitable for you. 

simple hypothesis

A simple hypothesis will only test and test the relationship between two variables: the independent variable and the dependent variable. As we have previously exemplified using study time and grades.

complex hypothesis

A more complex hypothesis involves a relationship between more than two variables, say: two independent variables and one dependent variable or vice versa. 

Example: The greater the poverty, the greater the illiteracy in society, the higher the crime rate.

null hypothesis

A null hypothesis, abbreviated as H0, is one in which there is no relationship between the variables. 

For example, poverty has nothing to do with the crime rate of a society.

alternative hypothesis

Along with a null hypothesis, an alternative hypothesis (H1 or HA) is used. It states the inverse of the null hypothesis, which implies that only one must be true. 

For example, poverty is the cause of society’s crime rate.

compound hypothesis

A compound hypothesis is one that does not predict the exact parameters, distribution, or range of the dependent variable. 

We often predict an exact outcome. “23-year-old men measure 189 cm on average”, for example. Here we provide an exact parameter. Consequently, the hypothesis is not composite. 

However, we cannot always formulate a precise hypothesis. In these cases, we could say: “On average, 23-year-old men are not 189 cm tall.” We have not established a distribution range or precise parameters for the mean height of 23-year-old men. Consequently, we have introduced a composite hypothesis instead of an exact hypothesis. 

An alternative hypothesis (as discussed above) is usually composite because it is defined as anything other than the null hypothesis. Since this “everything but” does not specify the parameters or the distribution, it is an example of a compound hypothesis.

logical hypothesis

A hypothesis that can be logically verified is known as a logical hypothesis. Thus, without actual evidence, a logical hypothesis suggests a relationship between variables. 

Example: Alligators have green scales, so it’s very likely that closely related dinosaurs had them too. However, since they are all extinct, we must rely on logic and not empirical data.

empirical hypothesis

An empirical hypothesis is the opposite of a logical hypothesis. It is a hypothesis that is being tested through scientific research, it is based on concrete data. It is also known as a “working hypothesis”.

Example: The life of cows is reduced by feeding them 1 pound of corn per day.

statistical hypothesis

A statistical hypothesis uses representative statistical models to draw conclusions about broader populations. Instead of testing everything, a subset is tested and the rest generalized based on previously collected data. 

Example: Naturally red hair is found in about 2% of the world’s population.

Directional hypothesis

A directional hypothesis predicts whether the effect of an intervention will be positive or negative before the test itself. 

Example: Does rain affect the amount of moderate to high intensity exercise people do per week? Positively, the rain reduces the amount of moderate to intense exercise that people do per week.

How to write a hypothesis in six steps

1. Ask a question

Writing a hypothesis implies having a question to answer. The question should be direct, concrete and specific. To help identify it, frame this question with the six classic ones: who, what, where, when, why or how. But remember that a hypothesis must be a statement and not a question.

2. Gather primary research

Gathering background information on the topic may require reading various books, academic journals, experiments, and observations, or it may be as simple as an Internet search.

Remember to consider your questions from multiple perspectives; conflicting research can be extremely helpful in developing a hypothesis; you can use your conclusions as possible rebuttals and frame your study to address these concerns.

3. Define your variables

Once you have determined what the question will be, you need to identify the independent and dependent variables, as well as the type of assumptions that apply.

4. Put it in the form of an if-then statement

When constructing a hypothesis, it can be helpful to use an “if-then” format. For example: “If I exercise more, I will lose more weight.” This format can be tricky when dealing with multiple variables, but in general it is a reliable way of expressing the cause-and-effect relationship that is being tested.

5. Collect more data to prove your hypothesis

The priority over a hypothesis is to answer the question and prove that it is correct or incorrect. Once you have established your hypothesis and determined your variables, you can begin your experiments. Ideally, you should gather data that supports your hypothesis.

6. Write it down

Finally, once you have written your hypothesis, analyze all the data you have collected and draw your conclusions in the form of a research paper.

Unleash the power of infographics with Mind the Graph

Take this opportunity to include a visual tool in your research paper to help clarify your hypothesis. Mind The Graph transforms scientists into designers to increase the visual impact of your research with scientific images and infographic templates.