A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expense among three industries rejected the null hypothesis. The mean square error (MSE)was 195. The following table summarized the results: Based on the comparison between the mean annual computer technology expense for companies in the education and tax services industries,________.
A)a confidence interval shows that the mean annual computer technology expenses are not significantly different
B)the ANOVA results show that the mean annual computer technology expenses are significantly different
C)a confidence interval shows that the mean annual computer technology expenses are significantly different
D)the ANOVA results show that the mean annual computer technology expenses are not significantly different

Question

A random sample of 40 companies with assets over $10 million was surveyed and asked to indicate their industry and annual computer technology expense. The ANOVA comparing the average computer technology expense among three industries rejected the null hypothesis. The mean square error (MSE)was 195. The following table summarized the results:  Based on the comparison between the mean annual computer technology expense for companies in the education and tax services industries,________.
A)a confidence interval shows that the mean annual computer technology expenses are not significantly different 
B)the ANOVA results show that the mean annual computer technology expenses are significantly different 
C)a confidence interval shows that the mean annual computer technology expenses are significantly different 
D)the ANOVA results show that the mean annual computer technology expenses are not significantly different

Quizplus · Accepted Answer

Since the ANOVA rejected the null hypothesis, we know that at least one of the mean annual computer technology expenses for the three industries is significantly different. To compare the education and tax services industries, we need to conduct a separate hypothesis test or calculate a confidence interval. Based on the information given, it is not possible to conduct a hypothesis test, but we can calculate a confidence interval. If the confidence interval does not include zero, then the mean annual computer technology expenses for the two industries are significantly different.

A Random Sample of 40 Companies with Assets Over $10