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A company that sponsors LSAT prep courses would like to be able to claim that their courses improve scores. To test this, they take a sample of 20 people, have each take an initial diagnostic test, then take the prep course, and then take a post-test after the course. The test results are below (scores are out of 100%):
Person1234567891011121314151617181920Initial Test7368707979606880637865687367606277647069Post-Test7075767493566987778170817377637578706766
Is there evidence, at an α=0.01α=0.01 level of significance, to conclude that the prep course improves scores? Carry out a Wilcoxon signed rank test, filling in the information requested. (Arrange your data so that the standardized test statistic is for the change from the initial test to the post-test.)
(a) The value of the test statistic:
(b) The rejection region for the standardized test statistic:
(c) Your decision for the hypothesis test:
A. Reject HaHa.
B. Reject H0H0.
C. Do Not Reject H0H0.
D. Do Not Reject HaHa.
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