India - Housing Condition and Migration Survey: NSS 49th Round, Schedule 1.2, January - June 1993 

A two-stage stratified design was adopted for the 49th round survey. The first-stage units(fsu) were census villages in the rural sector and U.F.S. (Urban Frame Survey) blocks in the urban sector (However, for some of the newly declared towns of 1991 census for which UFS frames were not available, census EBs were first-stage units). The second-stage units were households in both the sectors. In the central sample altogether 5072 sample villages and 2928 urban sample blocks at all-India level were selected. Sixteen households were selected per sample village/block in each of which the schedule of enquiry was canvassed. The number of
sample households actually surveyed for the enquiry was 119403.


Sample frame for fsus : Mostly the 1981 census lists of villages constituted the sampling frame for rural sector. For Nagaland, the villages located within 5 kms. of a bus route constituted the sampling frame. For Andaman and Nicobar Islands, the list of accessible villages was used as the sampling frame. For the Urban sector, the lists of NSS Urban Frame Survey (UFS) blocks have been considered as the sampling frame in most cases. However, 1991 house listing EBs (Enumeration blocks) were considered as the sampling frame for some of the new towns of 1991 census, for which UFS frames were not available.


Stratification for rural sector : States have been divided into NSS regions by grouping contiguous districts similar in respect of population density and crop pattern. In Gujarat, however, some districts have been split for the purpose of region formation, considering the location of dry areas and distribution of tribal population in the state. In the rural sector, each district with 1981 / 1991 census rural population less than, 1.8 million/2 million formed a separate stratum. Districts with larger population were divided into two or more strata, by grouping contiguous tehsils.

Stratification for urban sector : In the urban sector, strata were formed, within the NSS region, according to census population size classes of towns. Each city with population 10 lakhs or more formed a separate stratum. Further, within each region, the different towns were grouped to form three different strata on the basis of their respective census population as follows : all towns with population less than 50,000 as stratum 1, those with population 50,000 to 1,99,999 as stratum-2 and those with population 2,00,000 to 9,99,999 as stratum-3.

Sample size for fsu's : The central sample comprised of 5072 villages and 2928 blocks.

Selection of first stage units : The sample villages have been selected with probability proportional to population with replacement and the sample blocks by simple random sampling without replacement. Selection was done in both the sectors in the form of two independent sub-samples.

There was no deviation from the original sample deviation.

Sample weights were calculated and included in each of the data files
Variable 'Wgt_SS' refers to Multiplier for each Subsample.
Variable 'Wgt_Combined' refers to Combined Multiplier.