COMPARISON OF POST HOC TEST ON NON-COMMUNICABLE DISEASES DATA
Keywords:
Kruskal Wallis test, Post hoc tests, Nemenyi test, Dunn's test, Pairwise Mann-Whitney testAbstract
The Kruskal-Wallis test is a nonparametric statistical test that compares three or more independent sampling groups on a single continuous variable with non-normal distribution. When the Kruskal-Wallis test produces a significant result, it shows that at least one of the samples is different but the test does not show where or how the differences exist. So, post hoc tests are performed to find the significant differences among the sampling groups. This study aims to perform three different post hoc tests on the secondary data sets, identify the significant difference, and compare the performance of the post hoc tests. The post hoc tests namely the Nemenyi test, Dunn’s test, and Pairwise Mann-Whitney test are used in this study. The secondary data involved kidney disease, breast cancer, and heart failure. When comparing the performance of the post hoc tests, all three post hoc tests yield the same results for kidney disease and breast cancer data whereas the Pairwise Mann-Whitney test yielded different results compared to the other two post hoc tests for heart failure data. Dunn’s test is suitable to be used as the post hoc test as it yields a smaller p-value compared to other tests.
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