anova-two-way-variables (dv iv1 iv2)
Calculates the analysis of variance when there are two factors that may
affect the dependent variable, specifically iv1' and iv2.' 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; that
is, the same number of values (of the dependent variable) for each combination
of the independent factors.
The result of the analysis is an anova-table, as described in the manual. This
function differs from anova-two-way-groups' only in its input representation.<br> See the manual for further discussion of analysis of variance. <br> The row effect is iv1' and the column effect is `iv2.'