11. A 23 experiment was performed by an industrial engineer and the results are given in Table 4.16. Half of the experiment was done on one day and the remaining half on the next day. (a) Compute the main effect of task. (b) Use a half-normal plot to detect signicant factorial effects. Compare your nding with those based on the IER version of Lenth's method at an appropriate or level. {(3) With the timing mechanism operating properly, the standard deviation of the readings of average response time is known to be about 1 (o = l). Table 4.16 Task Efficiency Experiment Randomized Average Response Order in Which Inertia Time (tenths of Experiments Setup Flasher Type of Lever Task second) Were Performed Low Y 11 Low 12 High 10 High 11 DO JONWUA- DO -JOUAWN- A Low NNNN -KK 16 B Low 14 High 15 High 19 Run Part Width Filler Temperature Pull-off Force 36 40 80 50 20 45 Subsequent to carrying out this experiment, however, it was discovered that the timing device, although it had been operating properly on the first day, had not been operating properly on the second day. On that second day, the standard deviation was o = 4. Given this information, what is the variance of the main effect of task computed in part (a) above? (Hint: The derivations are similar to but more elaborate than those for (4.14).)