Page 209 - Contributed Paper Session (CPS) - Volume 2

CPS1824 Sanggi L.
Table-3 shows estimation results of net addition of population by birth in
shared weights method and direct calculation method. There is no significant
difference in the 0 years old by 2016, but the difference is significant in the 0-
1 years old by 2017. Direct calculation method includes 99.3% of the
population, but shared weights method includes only 84.1%. Also in shared
weights method, weights less than 1 occur.
Table-3 : estimation results
(unit : persons, %)
Reference shared weights direct calculations
year classification pop.(A)
est.(B) B/A min max est.(C) C/A min max
2016 0 years old 410,052 402,203 98.1 1.0 99.0 403,140 98.3 2.0 104.6
2017 0-1 years 771,317 648,560 84.1 0.7 111.2 765,758 99.3 2.1 104.2
old

3.5. Examples
Figure 2 shows that the initial weights for household with general entrants
1
who were in the population at wave 1 are assigned as (H1) = .
1−(1− 1 )(1− 2 )
And figure 3 shows that the initial weights for births or recent immigrants who
1
were not in the population at wave 1 are assigned as (H1) = .
1

Figure-2: General entry Figure-3: Birth, Recent immigrants

1
Those for household split are calculated as (H2) = . For
1−(1− 1 )(1− 2 )
1
household merge, the initial weights are computed as (H1) = .
1−(1− 1 )(1− 2 )
As a result in the method of directly calculating the selection probability and
assigning the initial weight, the only wave 1 selection probability is important
regardless of the type of variation of the household composition such as
household split, merging household, birth, etc.

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