Microsoft Word - AMICS-29Jan2013 - Childinfo.org

Since the estimated number of households in each EA in the sampling frame used for the first stage
selection and the updated number of households in the EA from the listing were different, individual
sampling fractions for households in each sample EA (cluster) were calculated. The sampling fractions
for households in each EA therefore included a first stage probability of selection of the EA in that
particular sampling stratum and a second stage probability of selection of a household within the
sample EA. Based on the sample design for the Afghanistan MICS4, the resulting basic weight for the
sample households can be expressed as follows:
W
hi
M h
=
nh
M
hi
M '
m
hi
hi
,
where:
W hi = basic weight for the sample households in the i-th sample EA in stratum h
M h =
total number of households in the sampling frame of EAs for stratum h
n h = number of sample EAs selected in stratum h for MICS 4
M hi = total population in the frame for the i-th sample EA in stratum h
M' hi = total number of households listed in the i-th sample EA in stratum h
m hi = 30 = number of sample households selected in the i-th sample EA in stratum h
Another component in the calculation of sample weights takes into account the level of non-response
for the household and individual interviews. The response rate for sample households in stratum h is
defined as follows:
RR h = Number of interviewed households in stratum h/ Number of occupied households listed in stratum h
The weight adjustment for household non-response is equal to the inverse of this response rate.
After the completion of fieldwork, response rates were calculated for each sampling stratum. These
were used to adjust the sample weights calculated for each cluster. Response rates for the
Afghanistan MICS4 are shown in Table 3.1 in this report.
Similarly, the adjustment for non-response at the individual level (women and under-5 children) for
each stratum is equal to the inverse value of:
RR h = Completed womens (or under-5 s) questionnaires in statum h / Eligible women (or under-5s) in stratum
h
The non-response adjustment factors for women's and under-5's questionnaires are applied to the
adjusted household weights. Numbers of eligible women and under-5 children were obtained from
the roster of household members in the Household Questionnaire for households where interviews
were completed.
152