Final answer:
In two-way between-subjects ANOVA, the degrees of freedom for factor A (dfA) are calculated as df = a - 1, where a is the number of levels of factor A.
Step-by-step explanation:
In a two-way between-subjects ANOVA, the degrees of freedom for factor A (dfA) is calculated based on the number of levels of factor A minus one. The correct formula to calculate this is df = a - 1, where a represents the number of levels of factor A. This formula is fundamental in the ANOVA table as it helps determine the within-group and between-group variability and consequently aids in the assessment of the statistical significance of the variation caused by the factor being analyzed.
For instance, if factor A has 5 levels, the degrees of freedom for factor A would be 5 - 1 = 4. The degrees of freedom are used to calculate various sum of squares in the ANOVA, which are critical for determining the mean squares and ultimately the F statistic for the ANOVA. Understanding the calculation of degrees of freedom is essential for interpreting the results of an ANOVA correctly.