Chapter 11 Problem 5

In a study of the effect of fatigue on performance of simple tasks, volunteers were instructed to perform a data entry task as rapidly and as accurately as possible. The number of errors committed during four 15-minute time periods was recorded. Did fatigue influence performance? Use the LSD test to make all pairwise comparisons after a significant F ratio.

Person	1st 15 Minutes	2nd 15 Minutes	3rd 15 Minutes	4th 15 Minutes
1	4	2	8	10
2	5	5	12	10
3	11	11	14	20
4	16	18	15	23
5	4	4	11	17

How many dependent variables are there? What is(are) it(they)? ( point)

How many independent variables are there? What is(are) it(they)? How many levels are there for each IV? ( point)

Hypothesis Testing

Step 1: ( point)

Step 2: ( point)

Step 3: = 0.05

Step 4: ( point)

Reject H₀ if

Step 5: (4 points, 2.5 for hand calculation and 1.5 for SPSS output)

F_comp =

Include your calculations on a separate sheet of paper. Also, cut and paste the SPSS Output table below. Again, be sure to circle the F-ratio and p-value. If you obtain a significant F-ratio, be sure to include your Fisher's LSD calculation and table of mean differences.

Step 6: Circle your decision below: ( point)

1. Reject H₀
2. Fail to reject H₀

Step 7: Conclusion: Was the number of errors the same during the four time periods? ( point)

1. Yes, the number of errors was the same during the four time periods.
2. No, the number of errors was not the same during the four time periods.

Conclusion continued: Which of the following time periods were significantly different with regard to the number of errors? (Circle all that apply.) ( point)

1. First 15 Minutes and Second 15 Minutes
2. First 15 Minutes and Third 15 Minutes
3. First 15 Minutes and Fourth 15 Minutes
4. Second 15 Minutes and Third 15 Minutes
5. Second 15 Minutes and Fourth 15 Minutes
6. Third 15 Minutes and Fourth 15 Minutes
7. None of the above
8. Please compare the groups using a one-way repeated measures ANOVA and type your responses below. Please show the seven steps for hypothesis testing and include the ANOVA summary table. If obtain a significant F-ratio, use Fisher's LSD to determine which groups differ. Please show the LSD calculation and the table of mean differences. Please provide the analyses in SPSS. Provide the SPSS output table and circle or highlight the F-ratio and p-value