A hypothesis is an educated guess that's formed at the beginning of a science experiment, but it can be used in almost every field and offer insight into your expectations and why they may or may not have been met after taking certain actions. Knowing the full definition of a hypothesis and learning how to plan and follow one can help you in any stage of your career. In this article, we define what a hypothesis is and offer examples that provide more context about how to use and interpret hypotheses.
What is a hypothesis?
A hypothesis is a potential explanation for something that happens or that you observe and think to be true. It can also be used to determine the relationship between two or more variables that you think might be related to each other.
Hypotheses are usually written as if/then statements, such as if someone eats a lot of sugar, then they will develop cavities in their teeth. These statements identify specific variables (in this case, eating a large amount of sugar) and propose a result (in this case, teeth developing cavities).
When creating a hypothesis, it's best to make it as strong as possible before conducting experiments or making further observations. This can be achieved by asking questions and brainstorming, being specific in the language you use and being logical and making sure the hypothesis is testable within constraints.
A scientific hypothesis must be about something that can be proved or disproved through experimenting or observation. Scientific hypotheses require extensive research and experimentation as well as the controlling of dependent and independent variables in order to produce an expected result, whether it supports the hypothesis as true or proves that it's incorrect.
Types of hypotheses
Hypotheses are used in science experiments, but they can also be helpful in identifying patterns, finding solutions or improving relationships in the workplace. When making an educated guess about an observed phenomenon, there are many different types of hypotheses to can consider using and learning from, such as:
- Simple hypothesis: A simple hypothesis predicts a relationship between an independent and a dependent variable.
- Complex hypothesis: A complex hypothesis looks at the relationship between two or more independent variables and two or more dependent variables.
- Empirical hypothesis: An empirical hypothesis can also be called a working hypothesis and is accepted as a basis for future research in order to formulate a theory for testing.
- Null hypothesis: A null hypothesis is the default position that assumes that the variables have no relation to each other.
- Alternative hypothesis: An alternative hypothesis is created to disprove a null hypothesis and adapts its method and prediction according to its results.
- Logical hypothesis: A logical hypothesis offers an explanation without extensive evidence.
- Statistical hypothesis: A statistical hypothesis evaluates a limited portion of a population and uses statistics to assess the results.
How to test a hypothesis
Here are five steps for testing a hypothesis:
1. Formulate a hypothesis
To test a hypothesis, it is important to take all the necessary steps to form an effective one. Follow these steps to do:
- Make an observation.
- Ask a question based on that observation.
- Research possible outcomes of your question.
- Consider all variables that impact or relate to your question.
- Make sure the hypothesis is testable and able to be proved or disproved.
2. Identify the null hypothesis
Identify one possible result of the experiment that shows no connection between any variables. Then, write this out as a statement. For example, someone whose original hypothesis is if an office provides food for snacks, employees will take fewer off-site breaks might reach the null hypothesis of the number of off-site breaks employees take is not related to the availability of food.
3. Specify the alternative hypothesis
Determine the alternative outcome of the null hypothesis that disproves it. The alternative hypothesis differs from both the null hypothesis and the original hypothesis. Considering the previous example, if the original hypothesis is: i**f an office provides food for snacks, employees will take fewer off-site breaks, and the null hypothesis is: the number of off-site breaks employees take is not related to the availability of food, then a potential alternative hypothesis would be: if an office provides food for snacks, employees will take more off-site breaks to obtain different food they prefer.
4. Conduct an experiment
Gather any materials that are necessary to complete the testing and make a plan for conducting the experiment. Include steps for gathering resources, observing, taking notes and stages of the experiment to ensure it's progressing. Then, follow that plan closely to ensure the hypothesis is tested thoroughly.
Consider the example hypothesis of: i**f an office provides food for snacks, employees will take fewer off-site breaks. An experiment for this hypothesis might look like this:
- Gather materials such as snacks for the office and a pen and paper or computer spreadsheet to keep tallies on.
- Keep track of how many employees take breaks off-site during one week.
- Set up snacks in an office every day for the next week.
- Observe and record how many employees choose the provided office snacks and how many still take an off-site break.
5. Evaluate the results
Look over the results of the completed results and compare them to the predictions made in your original hypothesis. This step helps to determine whether the original hypothesis was correct or whether the experiment proved the null hypothesis or the alternative hypothesis instead. Regardless of the results, the information from testing a hypothesis can be used to make new observations and, perhaps, form another hypothesis.
Examples of hypotheses
Here are a few examples of hypothesis with explanations of why they classify as certain types:
- If an office provides food for snacks, employees will take fewer off-site breaks: This is an example of a simple hypothesis, as the independent variable is providing snacks at the office, and the dependent variable is whether fewer employees choose to take an off-site break.
- If the company has a holiday party and everyone in the office attends, then morale will rise and so will productivity: This is an example of a complex hypothesis, as a high number of variables would be involved in its testing, such as whether the company has a holiday party, how many employees attend, whether attendees experience a rise in morale and how company productivity is affected.
- If Susan doesn't like math, she will not want to work in accounting: This is an example of a logical hypothesis, as there may not be much factual evidence to support it. At this point, there is no indication of what kind of math Susan doesn't enjoy or whether accounting will involve that kind of math.
- Employees are not affected by the temperature in an office: This is an example of a null hypothesis, as it assumes no correlation between the two variables, which are the physical comfort of employees and the temperature inside the office where they work.
- If someone is friendly at work, then we can be friends outside of work: This is an example of an if/then statement that is not a hypothesis, as it contains vague language and no strong basis for controlled experimentation.