Exam 17: Introduction to Nonparametric Statistics

Assume that you are conducting a small sample Mann-Whitney U test where n₁ = 14 and n₂ = 16 and that U₁ = 98.Assuming that U1 has been found correctly,what is the value of U₂?

The makers of furnace filters recently conducted a test to determine whether the median number of particulates that would pass through their four leading filters was the same.A random sample of 6 of each type of filter was used with the following data being recorded: If the Kruskal-Wallis test is used with an alpha = .01,the null hypothesis should be rejected and the managers should conclude that the four filters do not allow an equal median number of particulates.

Which of the following tests would not be an example of nonparametric method?

The logic behind the Mann-Whitney U test is that if the hypothesis is true that the populations have equal central locations,then the sum of the ranks from each population will be approximately equal.

The distribution of T-values in the Wilcoxon Matched-Pairs Signed Rank test is approximately normal if the sample size (number of matched pairs)exceeds 25.

Which of the following is not a step involved in the Wilcoxon signed rank test?

In employing the Mann-Whitney U test,the sample data from the two populations are first combined and the ranks of the data are determined,but we keep track of which population each ranked item came from.

If a Mann-Whitney U test was performed and U₁ = 50 and U₂ = 40,if the sample from population 1 was 10,the sample size from population 2 was:

In the finding the critical value for the Wilcoxon signed rank test,what does "n" represent?

The makers of furnace filters recently conducted a test to determine whether the median number of particulates that would pass through their four leading filters was the same.A random sample of 6 of each type of filter was used with the following data being recorded: If the Kruskal-Wallis test is used,the test statistic is approximately H = 7.814.

Consider the situation in which a human resources manager wishes to determine whether the median number of days of sick leave per year is greater for female employees than for male employees.The following data represent random samples of males and females: If the manager is unwilling to assume that the populations are normally distributed,which of the following is the correct conclusion to reach if the test is conducted using a .05 level of significance?

Recently,a study was done to determine whether the median speed on a section of highway is the same for cars versus trucks.A sample of 12 cars (n₁ = 12)and 15 trucks (n₂ = 15)was collected.If the Mann-Whitney U test is to be performed using an alpha = .05 and if the U test statistic is calculated to be 68,the null hypothesis should be rejected.

The General Electric service department believes that the median time for a service call should be 30 or fewer minutes.To test this,the following random sample of service times was collected: Given that the managers do not wish to make the assumption that the population is normally distributed,the appropriate statistical test for testing about service times is:

Assume that a Kruskal-Wallis test is being conducted to determine whether or not the medians of three populations are equal.The sum of rankings and the sample size for each group are below. The value of the test statistic is H = 0.68.

In the Wilcoxon signed rank test for testing about a single population median,if the sample size is large (n > 20),the test statistic can be approximated by the standard normal distribution.

Assume that a Kruskal-Wallis test is being conducted to determine whether or not the medians of three populations are equal.The sum of rankings and the sample size for each group are below. What is the critical value for this test using a 0.10 level of significance?

In order to determine whether the median distance for the X-Special golf ball exceeds the median distance for the best-selling golf ball,six golfers were selected and asked to hit each ball with their driver.The distance was recorded.The following data were observed. Based on these data,and testing at an alpha = 0.025 level,the critical value for the Wilcoxon Matched Pairs Signed Rank test is 2.

The Wilcoxon signed rank test is used for testing hypotheses about a population median if the data are at nominal level.

Nonparametric statistical tests are used when:

The Wilcoxon signed rank test is used to test hypotheses about the population median.