Humor in magazine ads. Industrial Marketing Management (1993) published the results of a study of humor in trade magazine advertisements. A sample of 665 ads were categorized according to nationality (U.S., British, or German) and industry (29 categories, ranging from accounting to travel). Then a panel of judges determined the degree of humor in each ad using a 5-point scale (where 1 = not at all humorous and 5 = very humorous). The data were analyzed using a 3 × 29 factorial ANOVA, where the factors were nationality (at three levels) and industry (at 29 levels). The results of the ANOVA are reported in the accompanying table.∗

(a) Using α = .05, interpret the ANOVA results. Comment on the order in which the ANOVA F-tests should be conducted and whether any of the tests should be ignored.

(b) According to the researchers, ‘‘British ads were more likely to be humorous than German or U.S. ads in the Graphics industry. German ads were least humorous in the Grocery and Mining industries, but funnier than U.S. ads in the Medical industry and funnier than British ads in the Packaging industry.'' Do these inferences agree or conflict with the conclusions reached in part a? Explain.