Which of the following distributions approximates the Kruskal-Wallis test statistic H when the problem objective is to compare k distributions and the sample sizes are greater than or equal to 5?
A) Normal.
B) Chi-squared distribution with k - 1 degrees of freedom.
C) Student t-distribution with k - 2 degrees of freedom.
D) Either chi-squared distribution with k - 5 degrees of freedom or Student t-distribution with k + 5 degrees of freedom.

Question

Quizplus · Accepted Answer

The Kruskal-Wallis test statistic H approximately follows a chi-squared distribution with k - 1 degrees of freedom when the sample sizes are greater than or equal to 5. Therefore, option B is the best choice. The normal distribution is not appropriate for non-parametric tests like Kruskal-Wallis. The Student t-distribution is used for parametric tests and is not appropriate for the Kruskal-Wallis test, which is non-parametric. Option D is incorrect because the degrees of freedom for the chi-squared and t-distributions are not correct.

Which of the Following Distributions Approximates the Kruskal-Wallis Test Statistic