A senior accounting major at Midsouth State University has job offers from four CPA firms. To explore the offers further, she asked a sample of recent trainees how many months each worked for the firm before receiving a raise in salary. The sample information is submitted to Minitab with the following results:
anaylsis of variance:
source DF SS MS F P
Factor 3 32.33 10.78 2.36 0.133
Error 10 45.67 4.57
total 13 78.00
At the .05 level of significance, is there a difference in the mean number of months before a raise was granted among the four CPA firms?