Homework SourseLester Hollar is vice president for human resources for a la
Lester Hollar is vice president for human resources for a large manufacturing company. In recent years, he has noticed an increase in absenteeism that he thinks is related to the general health of the employees. Four years ago, in an attempt to improve the situation, he began a fitness program in which employees exercise during their lunch hour. To evaluate the program, he selected a random sample of eight participants and found the number of days each was absent in the six months before the exercise program began and in the last six months following the exercise program. Below are the results.
At the 0.10 significance level, can he conclude that the number of absences has declined? Hint: For the calculations, assume the \"Before\" data as the first sample.
| Lester Hollar is vice president for human resources for a large manufacturing company. In recent years, he has noticed an increase in absenteeism that he thinks is related to the general health of the employees. Four years ago, in an attempt to improve the situation, he began a fitness program in which employees exercise during their lunch hour. To evaluate the program, he selected a random sample of eight participants and found the number of days each was absent in the six months before the exercise program began and in the last six months following the exercise program. Below are the results. |
Solution
The degree of freedom =n-1=8-1=7
Given a=0.1, the critical value is t(0.1, df=7) =1.415 (from student t table)
Reject H0 if t > 1.415
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The test statistic is
t= mean difference/(s/vn)
=2.75/(2.375/sqrt(8))
=3.275
| 6.000 | mean Before | ||
| 3.250 | mean After | ||
| 2.750 | mean difference (Before - After) | ||
| 2.375 | std. dev. | ||
| 0.840 | std. error | ||
| 8 | n | ||
| 7 | df |
