In a stopwatch time study, the number of cycles that must be timed is a function of:
(I) the variability of observed times.
(II) the desired accuracy for the estimated job time.
(III) the desired confidence for the estimated job time.
A) I only
B) I and II only
C) II and III only
D) I, II, and III
E) I and III only

Question

Quizplus · Accepted Answer

All three factors mentioned have an impact on the number of cycles that should be timed in a stopwatch time study.

- Variability of observed times: If there is high variability in the observed times, then more cycles need to be timed to capture the full range of possible values. This ensures that the average time calculated is representative of typical performance. 
- Desired accuracy: If a high degree of accuracy is desired, then more cycles should be timed to reduce the level of uncertainty around the average time. 
- Desired confidence: If a higher level of confidence is desired in the estimated job time, then more cycles should be timed to reduce the margin of error around the average time.

Therefore, the best choice is D, which addresses all three factors.

In a Stopwatch Time Study, the Number of Cycles That