A guide to constructing a hypothesis

An hypothesis is an argument that one variable will or will not change in response to another. The argument is then tested or answered by conducting a scientific investigation or further research.

Part A: Research a topic so you can make an educated guess

1. Do some research into the topic.

Ask yourself - What do I already know? What further information do I need?

2. Analyse your current knowledge and that in the field.

Ask yourself - Are there gaps in what is known that your research might fill?

3. Generate some questions that you might be interested in knowing more about.

Think about some particular directions for your investigation, especially ones that interest you.

4. Look for information about what the answer might be.

Are there clues to help you make an educated guess?


Part B: Determining the structure of your hypothesis

5. Determine your independent variable.

This is the factor you will be deliberately changing. This is the cause.

6. Determine your dependent variable.

This is the factor you think will change in response to changing the independent variable. It will be measured and this is the effect.

7. Generate a simple hypothesis.

This is a statement about how you think the variables might be related. Use the structure below as a guide.

If          (I do this)          then         (this)         will happen

8. Ask yourself if you can make your statement directional?

A directional statement gives information about how one variable will affect the other. For instance, if I increase the intensity of light provided to a plant then the rate of photosynthesis will increase.

9. Be explicit.

Let the reader know exactly what ideas you are testing, in what population (age, sex, etc.) and what will provide evidence of the relationship between variables.

10. Ensure that you can test your hypothesis.

Ask yourself whether you can observe and measure the variables through scientific investigation.

11. Write a formal hypothesis.

Draw upon all previous points to write your hypothesis. Leave out any personal comment.