The data in the following table represent the number of hour

The data in the following table represent the number of hours of relief provided by five different brands of headache tablets administered to 25 subjects experiencing fevers of 38° C or more.

Tablet

                          A               B               C               D               E

                          5.2            9.1            3.2            2.4            7.1

                          4.7            7.1            5.8            3.4            6.6

                          8.1            8.2            2.2            4.1            9.3

                          6.2            6.0            3.1            1.0            4.2

                          3.0            9.1            7.2            4.0            7.6

                  Mean:      5.44          7.90          4.30          2.98          6.96

Total mean: 5.516

Total variance: 5.748

         Carry out a 1-way ANOVA ( = .05) to test the hypothesis that the mean number of hours of relief provided by the tablets is the same for all five brands by:

Specifying the null and alternative hypothesis. (1 pt)

Specifying the decision rule. (1 pt)

Calculating the test statistic by filling in the ANOVA table below.

Source

SS (3 pts)

df (1 pt)

MS (1 pt)

F (1 pt)

Effect

Error

Total

Determining the critical value. (1 pt)

Do you reject or fail to reject the null? (1 pt)

Do post-hoc tests need to be conducted? If so, use Tukey’s test. If not, explain why not. (1 pt)

Summarize your conclusion (including the results of the post-hoc analysis, if applicable) using words of the problem. (1 pt)

Solution