A company has 2,100 employees belonging to the following groups: production, 1,200; marketing, 600; management, 100; other, 200. The company president wants to obtain an estimate of the views of all employees about a certain impending executive decision. The president knows that the management employees' views are most variable, along with employees in the "other" category, while the marketing and production people have rather uniform views within their groups. The production people are the most costly to sample, because of the time required to find them at their different jobs, and the management people are easiest to sample.
a. Suppose that a total sample of 100 employees is required. What are the sample sizes in the different strata under proportional allocation?
b. Discuss how you would design an optimum allocation in this case.