A pharmaceutical company has developed a new drug that they believe increases focus and attention. To test this hypothesis, the company obtains 27 volunteers and randomly assigns 9 to each of three groups. The first group receives a placebo. The second group receives 50 mg of the drug. The third group receives 100 mg of the drug. After taking the treatment, participants complete a computerized focus task to measure their level of focus and attention. The percentage accuracy for each participant is shown in the table below:
Placebo
50 mg
100 mg
81
92
86
80
86
93
72
87
97
82
76
81
83
80
94
89
87
89
76
92
98
88
83
90
83
84
91
State the null and alternative hypotheses
Perform a one-way ANOVA (give the completed table)
At α=0.05, what do you conclude (give the value for F*)? Interpret your result.
If you rejected the null hypothesis, follow up with Tukey’s HSD. Interpret your results.