Calculates the analysis of variance when there are two factors that may affect the dependent variable. Because the input is represented as an array, we can refer to these two factors as the row-effect and the column effect. Unlike the one-way ANOVA, there are mathematical difficulties with the two-way ANOVA if there are unequal cell sizes; therefore, we require all cells to be the same size, and so the input is a three-dimensional array. The result of the analysis is an anova-table, as described in the manual. This function differs from `anova-two-way-variables' only in its input representation. See the manual for further discussion of analysis of variance.