An industrial safety program was recently instituted in the

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.

Solution

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