Page 148 - Contributed Paper Session (CPS) - Volume 6
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CPS1851 Hee Young Chung et al.
where = ( | ) = + . Thus, the sample distribution ( | ) is a
1
0
linear combination of population distributions ( | ) and ( | ) .
∗
Therefore, we have the following result:
0 1 2
1
1
2
2
( | ) = + + + ( + ) = + +
0
0
1
0
1
1
Now, if we use 1 2 ≈ 1 2 to simplify the calculation and let
0 + 1 0 + 1 ()
( | ) = () , then the corrected estimator is as follows.
2
1
()
( | ) = = − () (10)
+
0
1
b. Parameter estimation of linear response rate model
The parameters of linear response rate model are estimated by using
the following model similarly used in the exponential response rate parameter
estimation.
1
= + + (11)
1
0
Therefore, , can be estimated whenever we have the weight and the
1
0
data obtained from the substrata. Here it is assumed that is independent
and identically distributed.
c. The proposed estimator for a given stratum mean
(1) Simple mean estimator
Since the weight of a given stratum is constant, = = is used and
ℎ
the following equation is obtained for mean estimator
ℎ 1 ℎ
1
̅ ̂
= ∑ ∑ = ∑ ∑ = ̅ (12)
ℎ=1 =1 ℎ=1 =1
(2) Stratified weighted mean estimator
Since the weights of the substrata are different, the following mean
estimator is used.
ℎ
̅ ̂
= 1 ∑ ∑ (13)
ℎ ℎ
ℎ=1 =1
(3) Bias corrected estimator
̂
̂
The expected value () obtained from () = + and
1
0
̂ ̂
, obtained from the response rate model (11) are used. The
1
0
proposed estimator is as follows.
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