Wilcoxon Rank Sum

This statistic uses the Wilcoxon rank sum test to evaluate whether the difference between the median of the data in the survey unit and the median in the reference area is above or below the DCGLW. This test is used if contamination is present in the background.

Select Wilcoxon Rank Sum from the Statistics menu -> Number of Samples. SADA asks the user for a decision criteria, depending on the analysis type. Then, SADA presents the following window.


Compare survey unit concentration data with reference area data adjusted by adding the DCGL. Each survey unit measurement below an adjusted reference area measurement contributes evidence that the survey unit is clean and the null hypothesis should be rejected.

If the human health risk or ecological risk assessment module has been setup, then the table separates radionuclides, nonradionuclides, and unregistered contaminants.