The Best Tasting Ice Creams Are Generally High in Fat

Essay

The best tasting ice creams are generally high in fat content, which gives them a creamy texture. Four brands of ice cream were tested by consumers who graded their level of creaminess (A = very creamy to F = not creamy). Each brand was rated by a different group of consumers (the data are shown below). Are there differences in perceived creaminess among the four brands?
a. What nonparametric method is appropriate for analyzing these data?
b. State the null and alternative hypotheses.
c. Perform the test and state your conclusion at α = 0.10.
d. If these data did satisfy the assumptions for performing ANOVA, what are the disadvantages of using this nonparametric method instead?