Non-parametric tests are statistical tests that do not rely on specific assumptions about the population's distribution or data characteristics. These tests are used when the data does not meet the requirements for parametric tests or when dealing with ordinal or non-normal data.
Related terms
Mann-Whitney U test: A non-parametric test used to compare two independent groups' medians.
Wilcoxon signed-rank test: A non-parametric test used to compare dependent samples or matched pairs.
Kruskal-Wallis test: A non-parametric alternative to one-way ANOVA used for comparing three or more independent groups.