Exam 15: A:nonparametric Statistics

A Wilcoxon rank sum test for comparing two populations involves two independent samples of sizes 15 and 20. The nonstandardized test statistic (that is, the rank sum) is T = 210. Under these circumstances, what is the value of the standardized test statistic z?

What is the appropriate nonparametric method to compare two populations when the samples are independent and where the normality requirement necessary to perform the parametric test is NOT satisfied?

We can conduct nonparametric tests even with nominal and ordinal data.

How is the alternative hypothesis to be tested always stated in all applications of the Kruskal-Wallis test?

The nonparametric tests discussed in your text (Wilcoxon rank sum test, sign test, Wilcoxon signed-rank test, Kruskal-Wallis test, and Friedman test) all require that the probability distributions have which of the following properties?

We can conduct nonparametric tests only with data of a higher order than nominal or ordinal.

Nonparametric tests are methods of inference that make no assumptions whatsoever about the nature of underlying population distributions or their parameters.

The Spearman rank correlation 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.

Consider the following data set: 2.2, 2.3, 2.3, 2.5, 2.6, 2.7, 2.8, 2.8, 2.8, 2.9, 3.1, 3.2, and 3.5. What is the rank assigned to the three observations of value 2.8?

To use the Wilcoxon rank sum test as a test for location, which of the following conditions must we assume?

The Friedman test is a nonparametric test that can be used to compare more than two dependent samples when the assumptions for an analysis of variance are invalid.

Nonparametric procedures are often, and perhaps more accurately, called free-agent statistics.

Which of these tests is the nonparametric counterpart of the parametric t test of for matched pairs?

Which of the following statements correctly describes the Wilcoxon signed-rank test?

A Wilcoxon rank sum test for comparing two independent samples involves two samples of sizes 6 and 10. The alternative hypothesis is that the location of population 1 is different from the location of population 2. Using a 0.05 significance level, the appropriate critical value is 32.

Which of the following is a nonparametric method that is equivalent to the Wilcoxon rank sum test?

Which of the following techniques are statistical methods that require, among other assumptions, that the populations be normally distributed?

In the Wilcoxon signed-rank test, if two or more measurements have the same non-zero difference, signs ignored, then what would be the logical next step?

The Kruskal-Wallis test can be conducted as one- or two-tailed tests.

The Wilcoxon signed-rank test for matched pairs is the nonparametric counterpart of the paired two-sample t test of .