ABSTRACT
Probability distributions are described by specific mathematical functions with a few parameters that adjust the location and scale of the curve. Parametric tests are to test the values of the distribution coefficients (parameters) such as mean, standard deviation, or probability. Nonparametric tests are used when the population distribution is either not known or cannot be assumed. The sign test is used to compare the median (not mean) values of either paired data or data and their corresponding estimates. The Wilcoxon signed-rank test uses the relative magnitudes of the “+” and “-” deviations as additional information to include in a sign type of test. The statements will be dependent on the tests used, the level of significance for rejection, the hypothesis, the choice of the number of data, and number of bins in a histogram.
