Estimation the mean amount and obtain the bound for the estimate.
A certain firm specializing in the manufacture and sale of free time 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 outlet can be viewed as a cluster of employees, and total sick leave time for each store can be determined from records. Simple random 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).
Estimate an 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
|