Groups and subjects

By performing a leveneTest(), you can check whether or not the homogeneity of variance assumption holds for a given dataset. The assumption must hold for the results of an ANOVA analysis to be valid.

Recall from the first chapter that ANOVA makes use of F-statistics, or F-ratios, in which two types of degrees of freedom are involved. These degrees of freedom are defined as

$$df_a = a - 1$$

$$df_{s/a} = a(n - 1)$$

where the values $a$ and $n$ represent the number of groups and the number of subjects in each group, respectively.

Can you tell based on the output from leveneTest() how many groups and how many subjects are involved in our experiment?

Possible answers

There are 5 groups and 114 subjects.

There are 5 groups and 120 subjects.

There are 6 groups and 114 subjects.

There are 6 groups and 120 subjects.

Exercise

Groups and subjects

Instructions

Possible answers