Question: System data for the job shop of Exercise 1 revealed that the average time spent by a job in the shop was approximately 4 working days. The model made the following predictions, on seven independent repli-cations, for average time spent in the shop:
3.70 4.21 4.35 4.13 3.83 4.32 4.05
(a) Is model output consistent with system behavior? Conduct a statistical test, using the level of significance α = 0.01.
(b) If it is important to detect a difference of 0.5 day, what sample size is needed to have a power of 0.90? Interpret your results in terms of model validity or invalidity. (Use a= 0.01.)