Exam 15: A:nonparametric Statistics

The Friedman test is employed to compare two or more populations when the data are generated from a matched pairs experiment and are either ordinal or interval, but not normally distributed.

The sign test is a nonparametric test that (1) uses the directions of differences observed in a matched pairs sample to determine whether the relative frequency distributions of two statistical populations are identical to or different from one another, and (2) determines whether a sample comes from a population with a specified median.

In a normal approximation to the Wilcoxon rank sum test, the standardized test statistic is calculated as z = 1.80. In this case, what would the p-value be for a two-tailed test?

The Wilcoxon rank sum test is a nonparametric test that uses two independent simple random samples to determine whether the relative frequency distributions of two statistical populations of continuous values are identical to or different from one another.

The Friedman test is the nonparametric counterpart to the randomized block design of the analysis of variance.

To which of the following tests does a randomized block design analysis of variance test correspond?

In a normal approximation to the Wilcoxon rank sum test, the standardized test statistic is calculated as z = 1.96. For a two-tailed test, the p-value of the test is 0.025.

Given sample size and specified significance level , the probability of a Type II error is larger for a nonparametric test.

Which of the following is a characteristic of the Kruskal-Wallis test?

In a normal approximation to the sign test, the standardized test statistic is calculated as z = 2.17. If the alternative hypothesis states that the location of population 1 is to the right of the location of population 2, then the p-value of the test is 0.015.

A one-sample t test corresponds to a Kruskal-Wallis test.

If the Friedman test is applied to a data set that are generated from a randomized block experiment with three treatments and five blocks, then the rejection region at the 2.5% significance level is > 12.8325.

Under which of the following conditions is the rank correlation coefficient used?

The Mann-Whitney U test is a nonparametric test that measures the degree of association between two variables for which only rank-order data are available.

In a Wilcoxon rank sum test for independent samples, the two sample sizes are 4 and 6, and the value of the Wilcoxon test statistic is T = 25. If the test is a two-tail and the level of significance is 0.05, then the null hypothesis will be rejected.

Which of the following is a nonparametric method to compare two populations when the samples are matched pairs and the data are ordinal?

A parametric test is a hypothesis test that depends on certain specific assumptions about the probability distribution of population values or the sizes of population parameters.

In the case of the sign test, which of the following is the best formulation of the null hypothesis?

Which of the following is characteristic of the Friedman test?