nce ratings of a sample of 15 electrical repairmen employed by the company. An aptitude test is required by the human resources department to become an electrical repairman. The manager was able to get the score for each repairman in the sample. In addition, he determined which of the repairmen were union members (code = 1) and which were not (code = 0). The sample information is reported below.
Worker Job Performance Score Aptitude Test Score Union Membership
Abbott 58 5 0
Anderson 53 4 0
Bender 33 10 0
Bush 97 10 0
Center 36 2 0
Coombs 83 7 0
Eckstine 67 6 0
Gloss 84 9 0
Herd 98 9 1
Householder 45 2 1
Iori 97 8 1
Lindstrom 90 6 1
Mason 96 7 1
Pierse 66 3 1
Rohde 82 6 1
1. Use a statistical software package to develop a multiple regression equation using the job performance score as the dependent variable and aptitude test score and union membership as independent variables. (Round your answers to 3 decimal places.)
Performance = ____ + _____ aptitude + _____ union
2. Complete the table. (Round your answers to 3 decimal places.)
Predictor Coefficients Standard Error t p-value
Constant
Aptitude
Union
3. Find the Standard error, R2 and R2(adj).
S
R2 %
R-Sq(adj) %
4. Complete the ANOVA table
Analysis of Variance
Source DF SS MS F p-value
Constant 3
Aptitude 11
Union 14
5. How effective are these two variables in explaining the variation in job performance? (Round your answer to 1 decimal place.)
Adjusting for the number of independent variables, these variables explain _____ percent of the variation in performance
6. Compute the test statistic for union membership. (Round your answer to 3 decimal places.)
Value of test statistic _____
7. What is the effect of union membership on job performance?
On average, union membership increases the job performance score by _____
8. If you include an interaction, what is the regression equation? (Negative amounts should be indicated by a minus sign. Round your answers to 2 decimal places.)
Performance = _____ + ______ aptitude + ____ union + ____ x1 x2
9. Complete the following table. (Negative amounts should be indicated by a minus sign. Round your answers to 3 decimal places.)
Predictor Coefficient SE Coefficient t p-value
Constant
Aptitude
Union
X1X2
10. Compute the value of the test statistic for the interaction term.
Value of the test statistic ______