An industrial safety program was recently instituted in the computer chip indust
ID: 3024466 • Letter: A
Question
An industrial safety program was recently instituted in the computer chip industry. The average weekly loss (averaged over one month) in man-hours due to accidents in 10 similar plants both before and after the program are as follows:
Plant Before After
1 30.5 23
2 18.5 21
3 24.5 22
4 32 28.5
5 16 14.5
6 15 15.5
7 23.5 24.5
8 25.5 21
9 28 23.5
10 18 16.5
Determine at the 5 percent level of significance, whether the safety program has been proven to be effective.
Explanation / Answer
At 5% level the p-value is 0.0248 <0.05, hence, do not reject the null and conclude that the safety program has not been effective at 5% los
t-Test: Paired Two Sample for Means Before After Mean 23.15 21 Variance 36.55833333 19.16666667 Observations 10 10 Pearson Correlation 0.882524978 Hypothesized Mean Difference 0 df 9 t Stat 2.265949333 P(T<=t) one-tail 0.024845515 t Critical one-tail 1.833112933 P(T<=t) two-tail 0.049691031 t Critical two-tail 2.262157163