has part continuous probability distribution number of degrees of freedom Chi-square probability distribution Orlaith Burke Chi-square probability distribution with k degrees of freedom is a theoretical probability distribution which corresponds to the distribution of a sum of the squares of k independent standard normal random variables. Philippe Rocca-Serra Alejandra Gonzalez-Beltran dchisq(x, df, ncp = 0, log = FALSE) http://stat.ethz.ch/R-manual/R-patched/library/stats/html/Chisquare.html http://docs.scipy.org/doc/scipy/reference/generated/scipy.stats.chi2.html#scipy.stats.chi2 ready for release