The last of our four statistical tests, the Wilcoxon T test, is used for repeated measures and matched pairs designs. It is used when the hypothesis predicts a difference between two sets of data and when the data are ordinal or interval.
For Wilcoxon, the observed value must be less than or equal to the critical value for significance to be shown. This is the same procedure as the Mann-Whitney test. For X-squared and Spearman's rank, the observed value must be greater than or equal to the critical value for significance. I think that it is likely that you would be told this information as part of an exam question, but as this is always a dangerous thing to assume it is worth knowing the difference - especially as looking up critical values in a table has been a fairly common task in this question in recent years.
The step-by-step worksheet for Wilcoxon's test is here and the second worksheet is here. The 1-slide powerpoint explaining when to use Wilcoxon is here.
We also attempted an entire RM question from June 2010 which is here. The mark scheme is here.
For Wilcoxon, the observed value must be less than or equal to the critical value for significance to be shown. This is the same procedure as the Mann-Whitney test. For X-squared and Spearman's rank, the observed value must be greater than or equal to the critical value for significance. I think that it is likely that you would be told this information as part of an exam question, but as this is always a dangerous thing to assume it is worth knowing the difference - especially as looking up critical values in a table has been a fairly common task in this question in recent years.
The step-by-step worksheet for Wilcoxon's test is here and the second worksheet is here. The 1-slide powerpoint explaining when to use Wilcoxon is here.
We also attempted an entire RM question from June 2010 which is here. The mark scheme is here.
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