Mann–Whitney U test

a nonparametric test of centrality for ordinal data that contrasts scores from two independent samples to assess whether there are significant differences between the two sets of rankings. The statistic obtained from this test, U, is calculated by summing the number of ranks in one group that are smaller than each of the ranks in the other group. A Mann–Whitney U test is analogous to a one-way analysis of variance, except that the former is conducted with ranked data and the latter is conducted with continuous data. See also Wilcoxon–Mann–Whitney test. [Henry Berthold Mann (1905–2000), Austrian-born U.S. mathematician; Donald Ransom Whitney (1915–2001), U.S. statistician]

Browse dictionary by letter

a b c d e f g h i j k l m n o p q r s t u v w x y z

Psychology term of the day

March 17th 2025

principled negotiation

a procedure to resolve the conflict between individuals or groups that strives for a mutually beneficial resolution while acknowledging the value of ongoing relationships. The procedure has four main components: (a) separating interpersonal problems from the more substantive issues between the parties and dealing with each issue individually, (b) focusing on the parties’ real interests rather than on what they initially say they want, (c) developing possible solutions that benefit all parties, and (d) insisting on objective criteria for the parties’ decisions. [first described in 1981 by Roger Fisher (1922–2012) and William L. Ury, U.S. experts on negotiation]