The test scores for selected samples of sociology students w

The test scores for selected samples of sociology students who took the course from three different instructors are shown below.

                        Instructor A           Instructor B        Instructor C

                                83                            90                         85

                                60                            55                         90

                                80                            84                         90

                                85                            91                         95

                                71                            85                         80

At a = 0.05, test to see if there is a significant difference among the averages of the three groups.

Solution

Null hypothesis: there is no significant difference among the averages of the three groups.

Alternative hypothesis: there is a significant difference among the averages of the three groups.

The test statistic is

F=1.56

The p-value= 0.2493 (from F table)

Since the p-value is larger than 0.05, we do not reject Ho.

So we can not conclude that there is a significant difference among the averages of the three groups.