What is the difference between nonparametric and parametric statistics?

Answer) Parametric statistics is more common as compare to nonparametric statistics, it is called distribution free tests as well as it don’t assume that a specific distribution is being followed by the data. Nonparametric statistics is useful when assumptions of parametric statistics are not met, especially the assumption regarding data that is normally distributed. Parametric statistics is useful to test the group means and nonparametric statistics is useful to test group medians. In a parametric statistics, it is assumed that the variables of interest’s measurement is done on ratio or interval level. As opposed to the nonparametric statistics, wherein the interest variables are measured on ordinal or nominal scale.