I. Paired-sample t test
A. A researcher administered a depression scale to a random sample to get pretest scores. He then administered an anti-depression drug. Next he administered the scale again to determine posttest scores. Input the data as follows:
Participant Number / Pretest / Posttest1 / 10 / 9
2 / 12 / 9
3 / 9 / 10
4 / 15 / 15
5 / 11 / 8
6 / 14 / 10
7 / 8 / 9
8 / 13 / 10
9 / 12 / 7
1. Copy and paste into a spread sheet
2. What is the researcher’s hypothesis?
3. What is the null hypothesis?
4. What is the Pretest mean?
5. What is the Posttest mean?
6. What is the Difference?
7. What is the t test Probability?
8. Is it significant? At What level?
9. Write a statement of results.
B. A researcher administered a Self-Esteem scale to a random sample to get pretest scores. He then provided counseling. Next he administered the scale again to determine posttest scores. Input the data as follows:
Participant Number / Pretest / Posttest1 / 30 / 28
2 / 33 / 29
3 / 29 / 30
4 / 27 / 31
5 / 26 / 29
6 / 37 / 37
7 / 40 / 41
8 / 35 / 40
9 / 36 / 37
10 / 35 / 38
10. Copy and paste into a spread sheet
11. What is the researcher’s hypothesis?
12. What is the null hypothesis?
13. What is the Pretest mean?
14. What is the Posttest mean?
15. What is the Difference?
16. What is the t test Probability?
17. Is it significant? At What level?
18. Write a statement of results.
II. Independent-sample t-test
A. An experimental group received Calculus over the Internet while the control group took the course in a traditional classroom. Final examination scores are listed below:
Participant Number / Group* / Calculus Exam scores1 / 1 / 30
2 / 2 / 28
3 / 2 / 33
4 / 1 / 26
5 / 1 / 34
6 / 2 / 34
7 / 1 / 37
8 / 2 / 33
9 / 1 / 26
10 / 2 / 26
*1- Experimental , 2-Control
19. Insert the data into a spread sheet
20. What is the researcher’s hypothesis?
21. What is the null hypothesis?
22. What is the Experimental mean?
23. What is the Control mean?
24. What is the Difference?
25. What is the t test Probability?
26. Is it significant? At What level?
27. Write a statement of results.
B. Kean High School administered the same test to a random sample of students in the traditional math course and to a random sample of students in “Math – Who needs It.” The results for the experimental group (“Math- Who Needs It”) were recorded in grade distribution Test 1. The results of the control group were recorded in grade distribution Test 2.
28. Open the results for grade distribution test 1 and test 2.
29. What is the researcher’s hypothesis?
30. What is the null hypothesis?
31. What is the Experimental mean?
32. What is the Control mean?
33. What is the Difference?
34. What is the t test Probability?
35. Is it significant? At What level?
36. Write a statement of results.
37. What would you recommend as principal.
III. Scattergram & Correlation
A. Is there a correlation between SAT Verbal Scores and Freshmen GPA?
38. Copy and paste the following data into Excel:
Participant Number / Verbal SAT / GPA1 / 650.00 / 3.20
2 / 525.00 / 2.30
3 / 480.00 / 1.50
4 / 680.00 / 3.00
5 / 500.00 / 2.70
6 / 490.00 / 1.10
7 / 590.00 / 3.50
8 / 440.00 / 2.00
9 / 400.00 / .95
10 / 700.00 / 3.90
11 / 370.00 / 1.75
12 / 460.00 / 1.00
39. Construct a scattergram
40. Determine the correlation of the 2 variables
41. What is the Pearson r Correlation?
42. What statement can you make about Verbal SAT’s as a predictor of Freshman GPA?
B. Is there a correlation between attitude toward school and attendance?
43. Copy and paste the following data into Excel:
Participant Number / Attitude Toward School / Days Absent1 / 8 / 4
2 / 9 / 3
3 / 10 / 3
4 / 2 / 12
5 / 5 / 13
6 / 6 / 6
7 / 6 / 7
8 / 7 / 9
9 / 6 / 8
11 / 2 / 11
12 / 1 / 8
13 / 6 / 4
14 / 9 / 0
15 / 4 / 5
16 / 6 / 7
17 / 6 / 6
18 / 5 / 5
19 / 6 / 6
20 / 10 / 2
21 / 0 / 9
44. Construct a scattergram
45. Determine the correlation of the 2 variables
46. What is the Pearson r Correlation?
47. What statement can you make about attitude toward school as a predictor of school attendance?
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