Nonparametric Tests

Nonparametric tests involve testing whether the sampled data are from the same population when the population is not normally distributed or the underlying distribution is not known. Whether the population follows any kind of distribution is irrelevant, since the test does not depend on the underlying distribution. In fact, this testing method is not based on the comparison of parameters, but on the distributions. Therefore, nonparametric statistics make fewer assumptions about the nature of the underlying distributions. Furthermore, the statistical procedure of this method is both easy and convenient. As a result, nonparametric statistics are widely used, especially when there is not enough information.