Individuals in four different age groups are asked to rate, on a scale of 1 to 10, three flavors of ice creams. Each group has the same number of individuals. Median ratings by the individuals are grouped by the flavor of ice cream and by age group. Which nonparametric test could be used to see if there is a difference in median ratings among the four age groups and three flavors?
A)Wilcoxon signed-rank test
B)Friedman test
C)Mann-Whitney test
D)Kruskal-Wallis test

Question

Quizplus · Accepted Answer

The Friedman test is used to determine if there are differences in medians among three or more related groups. In this case, the three flavors of ice creams are the related groups, and the four age groups are the independent variables. Therefore, the Friedman test is appropriate for this scenario. The Wilcoxon signed-rank test and Mann-Whitney test are used for comparing two related or independent groups, respectively. The Kruskal-Wallis test is used to compare the medians of two or more independent groups.

Individuals in Four Different Age Groups Are Asked to Rate