Abstract
Short-cut formulas are given which permit the exact partition of chi-square from an r x c contingency table into (r - 1) x (c - 1) individual degrees of freedom. Each single degree of freedom chi-square is computed from a formula which is a function only of the observed frequencies. A general expression is given which permits the construction of such formulas for contingency tables of any order. The method is applied to some experiments which compare the effects of X and beta radiation on mitotic rates in grasshopper neuroblasts (Chortophaga viridifaciata).