Hello. My name is Chris O'Connor, I am a graduate student from the University of Hawaii in the meteorology department.
I am interested in performing the Wilcoxon-Mann-Whitney rank sum test (Mann-Whitney U statistic) on different variables (zonal wind, sea level pressure, sea surface temperature, etc) for La Nina events during two different epochs (1956-1982 and 1983-2010) in GrADS.
To do this I need to plot a certain variable (say SST), rank each grid point for each month during each of the La Nina seasons of the 2 epochs, and then perform the Wilcoxon-Mann-Whitney test using these ranks.
I need to perform this ranking test for each individual grid point value, and produce an image (say looking at the entire Pacific Ocean), which shows where the null hypothesis was rejected, and where the null hypothesis is kept. (The null hypothesis being that the data during two epochs are different.)
Do you know how to do this or anyone I can contact about ranking gridpoint data or preforming this stastical test in GrADS? Do you have any suggestions how I may go about performing this test?
Thank you in advance for any help!
UH Meteorology Department
Graduate Student firstname.lastname@example.org