India - Household Consumer Expenditure: NSS 50th Round, Schedule 1, July 1993 - June 1994

The sample design adopted for this round of survey was similar to that followed in the past surveys in its general aspects. The general scheme was a two stage stratified design with the first stage units being villages in the rural areas and urban frame survey blocks (UFS) in the urban areas. The second stage units were the households.

Sampling frame for first stage units:
The latest available lists of census villages (which are mostly the 1981 census lists) constitute the sampling frame for the rural sector. For Nagaland, the villages located within 5kms of a bus route constitute the sampling frame whereas, for Andaman & Nicobar Islands, the list of accessible villages constituted the sampling frame. For the urban sector, the lists of NSSO Urban Frame Survey (UFS) blocks have been considered as the sampling frame. However, for some of the newly declared towns of 1991 census for which UFS frame has not been received, the lists of 1991 census EBs have been considered as the sampling frame.

Region formation and stratification:
States were divided into regions by grouping contiguous districts similar in respect of population density and cropping pattern. In rural sector each district was treated a separate stratum if the population was below 2 million and where it exceeded 2 million, it was split into two or more strata. This cut off point of population was taken as 1.8 million ( in place of 2 million ) for the purpose of stratification for districts for which the 1981 census frame was used. In the urban sector, strata were formed, within each NSS region on the basis of population size class of towns. However, for towns with population of 4 lakhs or more the urban blocks were divided into two classes viz. one consisting of blocks inhabited by affluent section of the population and the other consisting of the remaining blocks.

Selection of first stage units :
Selection of sample villages was done circular systematically with probability proportional to population and sample blocks circular systematically with equal probability. Both the sample villages and the sample blocks were selected in the form of two or more independent sub-samples. In Arunachal Pradesh the procedure of cluster sampling has been followed. Further large villages/blocks having present population of 1200 or more were divided into a suitable number of hamlet- groups/ sub-blocks having equal population content. Two hamlet- groups were selected from the
larger villages while one sub-block was selected in urban sector for larger blocks.

Selection of households :
While listing the households in the selected villages, certain relatively affluent households were identified and considered as second stage stratum 1 and the rest as second stage stratum 2.

A total of 10 households were surveyed from the selected village/hamlet-groups, 2 from the first category and remaining from the second.
Further in the second stage stratum-2, the households were arranged according to the means of livelihood. The means of livelihood were identified on the basis of the major source of income as i) self-employed in non-agriculture, ii) rural labour and iii) others. The land possessed by the households was also ascertained and the frame for selection was arranged on the basis of this information.
The households were selected circular systematically from both the second stage strata.

In the urban blocks a different method was used for arranging the households for selection. This involved the identification means of livelihood of households as any one of a) self-employed, b) regular salaried/wage earnings, c) casual labour, d) others. Further the average household monthly per capita consumer expenditure (mpce) was also ascertained. All households with MPCE of (i) Rs. 1200/- or more (in towns with population less than 10 lakhs or (ii) Rs. 1500/- or more (in towns with population 10 lakh or more) formed second-stage stratum 1 and the rest, second-stage stratum 2.The households of second-stage stratum 2 were arranged according to means of livelihood class and MPCE ranges before selection of sample households. A total of 10 households were selected from each sample block as follows
(i) For affluent strata/classes : 4 households from second- stage stratum 1 and 6 households from second-stage stratum 2
(ii) For other strata/classes : 2 households from second-stage stratum 1 and 8 from second-stage stratum 2.
Households were then selected circular systematically with a random start.

Shortfall in the required number of household in any second-stage stratum was made up by increasing the quota for the other second stage stratum.

A total of 7284 sample villages (Rural) and 4792 sample blocks (Urban) were allotted in central sample. 6983 sample villages and 470 sample blocks were successfully surveyed covering 356351 persons in sample villages and 208389 persons in sample blocks.

There was no deviation from the original sampling design.

Two different weights have been provided in each file in the data set. Details are as follows:-

1. Weight for each sub sample is stored in the variable name : Wgt_SubSample
2. Combined subsample weight is stored in the variable name : Wgt_Combined