OCR S4 2014 June — Question 6

Exam BoardOCR
ModuleS4 (Statistics 4)
Year2014
SessionJune
TopicWilcoxon tests

6 A Wilcoxon rank-sum test with samples of sizes 11 and 12 is carried out.
  1. What is the least possible value of the test statistic \(W\) ?
  2. The null hypothesis is that the two samples came from identical populations. Given that the null hypothesis was rejected at the \(1 \%\) level using a 2 -tail test, find the set of possible values of \(W\).