 This choice of "plotting position" (choice of quantile of the theoretical distribution) has occasioned less controversy than the choice for Q–Q plots.The resulting goodness of fit of the 45° line gives a measure of the difference between a sample set and the theoretical distribution.A P–P plot can be used as a graphical adjunct to a tests of the fit of probability distributions, with additional lines being included on the plot to indicate either specific acceptance regions or the range of expected departure from the 1