1 A college uses two assessments, \(X\) and \(Y\), when interviewing applicants for research posts at the college. These assessments have been used for a large number of applicants this year.
The scores for a random sample of 9 applicants who took assessment \(X\) are as follows.
$$\begin{array} { l l l l l l l l l }
21.4 & 24.6 & 25.3 & 22.7 & 20.8 & 21.5 & 22.9 & 21.3 & 22.3
\end{array}$$
The scores for a random sample of 10 applicants who took assessment \(Y\) are as follows.
$$\begin{array} { l l l l l l l l l l }
20.9 & 23.5 & 24.8 & 21.9 & 23.4 & 24.0 & 23.8 & 24.1 & 25.1 & 25.8
\end{array}$$
The interviewer believes that the population median score from assessment \(X\) is lower than the population median score from assessment \(Y\).
Carry out a Wilcoxon rank-sum test, at the \(1 \%\) significance level, to test whether the interviewer's belief is supported by the data.
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