Assumptions

One way ANOVA

01 Independence of observations

• The data were collected using statistically valid sampling methods, and there are no hidden relationships among observations.
• If your data fail to meet this assumption because you have a confounding variable that you need to control for statistically, use an ANOVA with blocking variables.

02 Normally-distributed response variable

• The values of the dependent variable follow a normal distribution.

03 Homogeneity of variance

• The variation within each group being compared is similar for every group.
• If the variances are different among the groups, then ANOVA probably isn’t the right fit for the data.