Estimating proportions based on observations
You have twenty-five observations of university policeman Sgt. Jack B. Nimble during his normal workday. The results are shown here. Assume that the estimated proportion is to be within 5 percent of the true proportion 95 percent of the time.
Activity Observed
Number of Times Observed
Doing paperwork 9
On the phone 3
Eating doughnuts 3
Cleaning weapon 4
Idle 2
Not in sight 4
Based on your preliminary observations, how many total observations do you need to estimate the proportion of time Sgt. Nimble spends doing paperwork?
How many total observations do you need to estimate the proportion of time Sgt. Nimble spends on the phone?