Advanced topic: In a two-way analysis of variance,the degrees of freedom for each main effect are
A)the number of cells minus the number of variables.
B)the number of variables minus the total scores within the column or row.
C)the number of levels of the variable minus 1.
D)the total number of scores in that row or column minus 2.

Question

Quizplus · Accepted Answer

For each main effect in a two-way analysis of variance, the degrees of freedom are equal to the number of levels of the variable minus 1. This is because one degree of freedom is lost when estimating the mean of the variable from the data, and there are (number of levels - 1) observations left to estimate the variation within that variable. The other choices listed are not correct for determining the degrees of freedom in a two-way ANOVA.

Advanced Topic: in a Two-Way Analysis of Variance,the Degrees of Freedom