Living Standards Survey, Wave 3, 2010-2011

(a) SAMPLING FRAME

The initial frame for the LSS-III survey was based on the frame prepared for the 2008 Nepal Labour Force Survey (NLFS-II). This was done "to take advantage of the cartographic segmentation and household listing operations" conducted by the CBS for the NLFS-II. Number of households at ward level was obtained from the 2001 Population Census. CBS has constructed a data set with basic information (number of households, total population, and male and female population) at the ward level. This data set was used to construct the frame for the selection of primary sampling units (PSUs). The PSU for the NLFS-II were either individual wards or sub-wards or groups of contiguous wards in the same VDC. A group of wards was considered as single PSU, to ensure that each unit continued at least 30 households. For the ultimate sample selection of households in the NLFS-II, a frame was prepared in each ward selected at the earlier stage of sampling. A list of all households was prepared in all the wards selected for the survey. Selection of households was carried out from these listings using systematic sampling with a random start. Before the listing, an intensive cartographic work was undertaken (in the urban areas and some of the rural areas) to form appropriate enumeration block having around 200 households.

(b) STRATIFICATION

For the NLFS-II sample selection, 75 districts along with the urban and rural areas were grouped into six strata - mountains, urban areas of the Kathmandu valley, other urban areas in the hills, rural hills, urban hills, urban Tarai and rural Tarai. These six strata of the NLFS-II were further regrouped into 14 strata for the NLSS-III purposes. The "explicit" strata formed for the NLSS-III were as follows: mountains, urban areas of the Kathmandu valley, other urban areas in the hills, rural eastern hills, rural central hills, rural western hills, rural mid-western hills, rural far-western hills, urban Tarai, rural eastern Tarai, rural central Tarai, rural western Tarai, rural mid-western Tarai, and rural far-western Tarai.

(c) SAMPLE DESIGN

The sample design adopted in LSS-III was modified sub-sample of the sample adopted in NLFS-II. For the NLFS-II, 800 PSUs were selected - 400 PSUs each from urban and rural areas. As mentioned earlier, the PSU for the NLFS-II was a ward or a sub-ward or a combination of wards. The PSUs were selected with probability proportional to size, the measure of size being the number of households. For the LSS-III, two independent samples were selected: the first was a cross sectional sample and the second was a panel. The panel sample consisted of PSUs and households previously enumerated in one or both of the past two rounds of the survey.

(d) SAMPLE SIZE

The sample size for the survey was estimated at 7200 households in 600 PSUs. Among them, 100 PSUs with 1200 households interviewed in the LSS-I or LSS-II were selected for re-interviewing in the LSS-III. 500 PSUs with 6000 households were selected as the cross-section sample. The PSUs were selected with probability proportional to size, the measure of size being the number of households in each ward. As mentioned earlier, twelve households were selected for the enumeration from each of the selected PSU.