Rank sum test
A test of the homogeneity of two samples and based on the rank statistic — the sum of the ranks of the random variables in the joint series of order statistics (cf. Order statistic) of and (the elements of the two samples are mutually independent and come from continuous distributions). It is a variant of the Wilcoxon test.
Rank sum test. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Rank_sum_test&oldid=12062