I run into an unexpected behaviour of the "pvalue" utility, which crashes if required to compute the pvalue of a very small number using a Chi square with a large number of degrees of freedom. For instance, setting 227 degrees of freedom the pvalue is computed only for numbers larger than about 0.165. For lower values the reply is "impossible to compute the pvalue" in the GUI and "NA" in a batch script (v. 2016b, 2016-04-14) Of course, nobody in his right mind will knowingly want to compute such a pvalue, but when running in a script it may happen and the NA output does not look good.