t-Tests

Mock Study 1: t-Test for Independent Samples (20 points)

1. Six months after an industrial accident, a researcher has been asked to compare the job satisfaction of employees who participated in counseling sessions with those who chose not to participate. The job satisfaction scores for both groups are reported in the table below.

Use the five steps of hypothesis testing to determine whether the job satisfaction scores of the group that participated in counseling session are statistically different from the scores of employees who chose not to participate in counseling sessions at .01 level of significance. (Alpha = .01)

Clearly list each step of hypothesis testing. As part of Step 5, indicate whether the researcher should recommend counseling as a method to improve job satisfaction following industrial accidents based on evaluation of the null hypothesis.

Data to be entered in SPSS (instructions below)

PARTICIPATED IN COUNSELING	DID NOT PARTICIPATE IN COUNSELING
35	38
39	36
41	36
36	32
37	30
36	39
37	41
39	35
42	33
38	38

Step 1: Data managing

1. Open a blank SPSS data file: File New Data
2. In the blank SPSS data file, create your SPSS data set by entering the job satisfaction scores of those who participated/did not participate in the counseling sessions (reported on previous page). Please create two columns. Column one is the test variable, where you enter ALL the 20 scores in the table. Column 2 is the grouping variable, where you use "1" to indicate if a score is from someone who participated in the counseling sessions; and "0" to indicate if a score is from someone who chose not to participate in the counseling sessions. The data set will look like this in SPSS Data View window:

35 1

39 1

..........

38 0

36 0

..........

1. After data entry, go to Variable View window, change the name of the first variable (test variable) to "JOBSAT" and the second variable (grouping variable) as "group." Set decimals for both variables to zero.

Step 2: SPSS execution

1. Click: Analyze Compare MeansIndependent-Samples T Test use arrow to move JOBSAT to "Test Variable" use arrow to move "group" to "Grouping Variable"when two (? ?) appear, click Define Groups. On the next pop up window, enter "1" for "Group 1" and "0" to "Group 2."
2. Click OK.