Estimate the mean amount as well as obtain the bound for the estimate.
A definite firm specializing in the manufacture and sale of leisure clothing has 80 retail stores in Florida and 140 in California. With each state as a stratum the firm wishes to estimate average sick-leave time per employee for the past year. Each channel can be viewed as a cluster of employees, and total sick leave time for each store can be determined from records. Simple arbitrary samples of 8 stores from Florida and 10 from California gave the results shown in the table below (mi - # of employees, yi - total days sick leave for the i-th store).
Evaluation the average amount of sick leave per employee and obtain the bound for the estimate.
Florida
|
California
|
mi
|
yi
|
mi
|
yi
|
16
|
40
|
16
|
50
|
20
|
51
|
8
|
32
|
8
|
30
|
4
|
11
|
12
|
36
|
5
|
10
|
22
|
68
|
12
|
32
|
15
|
50
|
17
|
37
|
11
|
39
|
22
|
61
|
7
|
23
|
30
|
39
|
|
|
24
|
40
|
|
|
10
|
41
|