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Ho: probability distribution of populationl is identical to probability distribution of population 2
Ha: probability dist of populationl is to the right of probability distribution of population 2
Test statistic = T. = sum of negative ranks
Rejection region: Reject Hoif T. 5 To (Tram 0 ICING)
Ha: probability dist of populationl is to the left of probability distribution of population 2
Test statistic = T+ = sum of positive ranks
Rejection region: Reject HD if T+ 3 To
Ha: probability dist of populationl is different than probability distribution of population 2
Test statistic = smaller of T and T+ = T
Rejection region: Reject HQ if T 5 To
\ 1. Take differences 2. Take absolute value of diffs 3. Rank as before 4. Sum ranks n = # of onzero differences 0 (main qm tmhchJhN/W it out Ex: Recall the PARS ﬁle (govt agency evaluation scores). A random sample of 5 agencies was
taken. Assuming the differences in scores between 2008 and 2007 come from a nonnormal
#2 population, can you conclude the distribution of scores in 2008 is shifted above he distribution '2 O ofscores in 2007 atthe 5'? Si niﬁcance level? L” hl
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 Spring '13
 Leffakis

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