Suppose a research uses the Mann-Whitney U test to determine if there is a difference in the volume of text messages sent by a high school student living in a rural area versus an urban area during the month of December.Eight rural high school students and 9 urban high school students were included in the study.If, among all 17, the sum of the ranks W₂ produced from the urban high school is 88, the U₂ test statistic is _____________ A)29 B)45 C)90 D)43 E)20

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Quizplus · Accepted Answer

The Mann-Whitney U statistic is calculated using the formula U = n1*n2 + (n2*(n2+1))/2 - W2, where n1 and n2 are the sample sizes of the two groups, and W2 is the sum of ranks for the second group. Here, n1 = 8, n2 = 9, and W2 = 88. So, U = 8*9 + (9*(9+1))/2 - 88 = 72 + 45 - 88 = 29.

Suppose a Research Uses the Mann-Whitney U Test to Determine