Exam 15: A:nonparametric Statistics

In a Friedman test for comparing three populations, provided that there are five blocks, the test statistic is calculated as = 6.594. In this case, what is the most accurate statement that can be made about the p-value?

When the relationship between two variables is monotonically decreasing, what might the size of Spearman's rank correlation coefficient be?

In a Wilcoxon signed-rank test, the test statistic is calculated as T = 75. If there are n = 15 observations for which the difference is not 0, and a two-tailed test is performed at the 5% significance level, what is an appropriate conclusion?

The Wilcoxon rank sum test is used to compare two populations when the samples are independent but not normally distributed.

Which one of the following is NOT a reason for using a sign test to make a comparison between two populations?

A nonparametric test is one that makes no assumptions about the specific shape of the population from which a sample is drawn.

Given that n = 37, and the value of sample Spearman rank correlation coefficient = 0.35, then the value of the test statistic for testing is z = 2.10.

To apply the Wilcoxon rank sum test to determine whether the location of population 1 is different from the location of population 2, what kind of samples must be used?

Which of the following correctly states the difference between parametric and nonparametric statistical methods?

To apply the Friedman test to determine whether the locations of two or more populations are the same, what is a necessary property of the samples drawn?

The sign test is a nonparametric procedure for testing which of the following situations?

The first step in a Wilcoxon rank sum test is to combine the data values in the two samples and assign a rank of 1 to which of the following observations?

You are performing the Wilcoxon rank sum test. The 14th through 16th values in an ordered array of pooled sample data all equal $160 (while the 13th value is less and the 17th value is more). What are the appropriate ranks for the three $160 values?

Which of the following correctly describes the Wilcoxon rank sum test?

A paired sample, two-sample t test corresponds to which of the following tests?

The z-test approximation to the Wilcoxon rank sum test for two independent samples requires that both sample sizes are smaller than 10.

Which of these tests is a nonparametric method to compare two or more populations when the samples are independent and the data are either ordinal or interval but not normal?

The Spearman rank correlation test is a nonparametric test that 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.

In a Kruskal-Wallis test, there are five samples and the value of the test statistic is calculated as H = 12.32. Then the most accurate statement that can be made about the p-value of the test is that it is greater than 0.025 but smaller than 0.05.

Kruskal-Wallis test is a nonparametric test that can be used to compare more than two independent samples when the assumptions for an analysis of variance are invalid.