India - Common Property Resources, Sanitation Hygiene Services: NSS 54th Round, Schedule 31, January 1998 - June 1998

As usual, a stratified sampling design is adopted in this round. The first stage units are census villages ( panchayat wards in case of Kerala) in the rural sector and the NSSO Urban Frame Survey (UFS) blocks in the urban sector. The ultimate stage units are households in both the sectors.

Sampling frame for first stage units
(a) Rural : The lists of census villages of 1991 population census (1981 census list for J & K) constitute the sampling frame for the rural sector. For Kerala, however, the list of panchayat wards has been used as the sampling frame for selection of panchayat wards in the rural sector. For Nagaland, the villages located within 5 kms. of a bus route constitute the sampling frame, whereas, for Andaman & Nicobar Islands, the list of acces­sible villages constitutes the sampling frame.
(b) Urban : The lists of latest UFS blocks have been considered as the sampling frame for all cities and towns.

Stratification
(a) Rural : At first, the following three strata (namely strata types 1, 2 & 3) are formed at the level of each state/u.t.:-
Stratum 1 : list of uninhabited villages(as per '91 census).
stratum 2 : villages with population 1 to 50 (including both the boundaries)
stratum 3 : villages with population more than 15,000

Strata types 1, 2 & 3 above are formed provided there are at least 10 villages in each of the strata types in the state/u.t. as per 1991 population census. Otherwise, these villages are included in the general strata as described below :

After formation of the strata types 1, 2 & 3 (wherever applicable), the remaining villages of the state/u.t. are consid­ered for formation of general strata. Each district with popula­tion less than 2 million as per 1991 census forms a separate stratum (however, district having a population of 2 million or more is divided into a number of strata as per usual procedure followed in NSS). For Gujarat, some districts cut across NSS regions. In such cases, the part of a district falling in an NSS region forms a separate stratum.

(b) Urban : Strata are formed within NSS region by grouping towns.

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