This document discusses nonparametric tests based on ranks, including the Wilcoxon signed-rank test for paired samples, the Wilcoxon rank-sum test for two independent samples, the Kruskal-Wallis H test for comparing more than two independent samples, and the Friedman test for comparing treatments across multiple test attempts. Examples are provided to illustrate how to perform each test and interpret the results.

1. 12. Nonparametric test based on ranks

4. Supporting Area Rejection Area Rejection Area

10. T + =24.5; T - =41.5

19. (5) P -value and conclusion —— Compare with critical value of H ( C 7 ) or k : Number of samples Example 12.7: Conclusion: The weights are not all at an equal level.

20. 12.3.2 Friedman test for the data from a randomized block design Example 12.4 The riboflavin were tested for 3 samples of cabbage under four test conditions (A, B, C and D). The results are listed in Table 12.9. Now the question is if the test results are different in different kinds of test conditions.