Author Question: Recently, a legislative committee commissioned a study of incomes in a western state. At issue was ... (Read 54 times)

Engineer · **on:** Jun 24, 2018

Recently, a legislative committee commissioned a study of incomes in a western state. At issue was whether the ratings of the legislature's performance differed between rural citizens and city residents.

A random sample of 25 city residents and 35 rural residents was asked to rate the performance of the legislature on a scale of 1 to 100. The analysts believe that the population distribution of ratings would be highly skewed so they decided to use the Mann-Whiney U test to test whether there is a difference in median ratings by the two groups. Given this information, which of the following is the correct critical value if the test is to be conducted at the .10 level of significance?A) z = 1.96
B) t = 2.0357
C) U = 437.5
D) z = 1.645

Question 2

In a large sample Mann-Whitney U test in which the sample size from the first population is 30 and the sample size from the second population is 40, which of the following is the expected U value if the null hypothesis of equal median values is true?

A) 1,200
B) 70
C) 35
D) 600