<P> Nonparametric statistics is the branch of statistics that is not based solely on parameterized families of probability distributions (common examples of parameters are the mean and variance). Nonparametric statistics is based on either being distribution - free or having a specified distribution but with the distribution's parameters unspecified . Nonparametric statistics includes both descriptive statistics and statistical inference . </P> <P> The statistician Larry Wasserman has said that "it is difficult to give a precise definition of nonparametric inference". The term "nonparametric statistics" has been imprecisely defined in the following two ways, among others . </P>

Which of the following is not a characteristic of a nonparametric test