The 3 Rules:
choosing a statistical test

1. What type of data do you have?

• Normally distributed, OR

• Not normally distributed, OR

• Categorical data

​​

2. What questions are you asking?

• Differences of means/medians between groups of data

       OR​

• Relationships between variables

​

3. What is the experimental design?

• How many factors and groups?

       AND​

• Is the data in each group independent or related (or paired or repeated)?