preceded by has_specified_input has_specified_output achieves_planned_objective multiple testing correction objective data transformation multiple testing correction method false positive rate Kruskal Wallis test between group comparison objective between group comparison statistical test Conover-Iman test of multiple comparisons using rank sums Conover, W. J. and Iman, R. L. (1979). On multiple-comparisons procedures. Technical Report LA-7677-MS, Los Alamos Scientific Laboratory. Conover-Iman test for stochastic dominance is a stastical test for multiple group comparisons and reports the results among multiple pairwise comparisons after a Kruskal-Wallis test for stochastic dominance among k groups (Kruskal and Wallis, 1952). The interpretation of stochastic dominance requires an assumption that the CDF of one group does not cross the CDF of the other. The null hypothesis for each pairwise comparison is that the probability of observing a randomly selected value from the first group that is larger than a randomly selected value from the second group equals one half; this null hypothesis corresponds to that of the Wilcoxon-Mann-Whitney rank-sum test. Like the rank-sum test, if the data can be assumed to be continuous, and the distributions are assumed identical except for a difference in location, Conover-Iman test may be understood as a test for median difference. conover.test accounts for tied ranks. The Conover-Iman test is strictly valid if and only if the corresponding Kruskal-Wallis null hypothesis is rejected. Philippe Rocca-Serra posthoc.kruskal.conover.test(x, …) # S3 method for default posthoc.kruskal.conover.test( x, g, p.adjust.method = p.adjust.methods, …) # S3 method for formula posthoc.kruskal.conover.test(formula, data, subset, na.action, p.adjust.method = p.adjust.methods, …) https://www.rdocumentation.org/packages/PMCMR/versions/4.2/topics/posthoc.kruskal.conover.test conover.test makes k(k-1)/2 multiple pairwise comparisons based on Conover-Iman t-test-statistic of the rank differences. p-value ready for release