What is meant by the precision interval? What are the four factors that affect the size of the computed interval ? Calculate the precision interval, at a confidence level of 90%, for the errors in question 5-7.

Question 5-7:

What is meant by the point estimate of the total errors for difference estimation? Calculate the point estimate when there are the following client errors in a sample of 120 items from a population of 3,000 (understatements are in parentheses): 48.12, 56.11, 97.16, (41.14), 13.06, 191.67, (84.91), 1.56.