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The Kruskal–Wallis test by ranks, Kruskal–Wallis test (named after William Kruskal and W. Allen Wallis), or one-way ANOVA on ranks is a non-parametric statistical test for testing whether samples originate from the same distribution.
The test statistic, F, assumes independence of observations, homogeneous variances, and population normality. ANOVA on ranks is a statistic designed for situations when the normality assumption has been violated.
The critical value is the number that the test statistic must exceed to reject the test. In this case, F crit (2,15) = 3.68 at α = 0.05. Since F=9.3 > 3.68, the results are significant at the 5% significance level. One would not accept the null hypothesis, concluding that there is strong evidence that the expected values in the three groups ...
Kruskal-Wallis assumes that the errors in observations are i.i.d. (in the same way that parametric ANOVA assumes i.i.d. (,) errors; Kruskal-Wallis drops only the normality assumption). The test is designed to detect simple shifts in location (mean or median - same thing here) among the populations.
Test name Scaling Assumptions Data Samples Exact Special case of Application conditions ... Kruskal-Wallis test [11] Wilcoxon signed-rank test: interval: non-parametric:
Kruskal–Wallis one-way analysis of variance by ranks: tests whether > 2 independent samples are drawn from the same distribution. Kuiper's test: tests whether a sample is drawn from a given distribution, sensitive to cyclic variations such as day of the week. Logrank test: compares survival distributions of two right-skewed, censored samples.
The most common non-parametric test for the one-factor model is the Kruskal-Wallis test. The Kruskal-Wallis test is based on the ranks of the data. The advantage of the Van Der Waerden test is that it provides the high efficiency of the standard ANOVA analysis when the normality assumptions are in fact satisfied, but it also provides the ...
There are some alternatives to conventional one-way analysis of variance, e.g.: Welch's heteroscedastic F test, Welch's heteroscedastic F test with trimmed means and Winsorized variances, Brown-Forsythe test, Alexander-Govern test, James second order test and Kruskal-Wallis test, available in onewaytests R