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Unit Level Data


The results of the surveys conducted by the NSSO are published in different reports which are available to the data users through various channels of the Ministry of Statistics and Programme Implementation, Govt. of India. However, within one year from the completion of field work of a NSS round, DPD disseminates unit-level data of that round to the data users through the data warehouse maintained by the Computer Centre of the Ministry.  The latest available unit level data is of NSS 71st Round. NSS unit-level data on CDs, Rate List and Procedure for obtaining NSS data on payment of nominal price are available in the website of the Ministry.

The unit level data is organised in a number of formats (or levels).  Normally each level corresponds to one Block in the survey questionnaire.  The data fields in any particular level correspond exactly to the items or columns of the corresponding block in the survey questionnaire. There may be one or multiple number of data records in any level. Each record in a level may correspond to a household or person or activity or item of consumption and so on. In some of the levels two or more blocks of the schedule are merged together. 

With effect from NSS 65th Round onwards, the unit level data has been segregated level-wise and data of each level is presented in a separate file. This has been done to facilitate linking of data fields belonging to different levels/blocks.

For generating estimates for any characteristic in a domain (State, District etc.) from unit level data, one has to aggregate these data using the corresponding multipliers as weights. The estimation procedure of the NSS round describing exact formula for estimation, and detail procedures for use of multipliers for generation of estimates at disaggregate level, are available in the data CD supplied from the Computer Centre.

For convenience of the data user as to how to use the unit level data for tabulation, detail instructions have been given in a file named ‘Readme.txt’ which is contained in the data CD. It is important to read and understand the instructions in the file before proceeding to compile the data.          

Description of codes for State, District etc. is as per latest Population Census. The other codes used in the data have the meaning as given in the Survey Schedule. For handling the codes, the ‘String’ should be used, and not its numeric value.

DPD handles all aspects of data processing of the National Sample Surveys right from sample selection, data entry, verification, validation to preparation of tables on different characteristics of the socio economic surveys. Accordingly, DPD provides appropriate assistance to the data users regarding various queries raised by them related to the data of NSS. Any query regarding the usage of unit level data may be forwarded by email to dpd_tc@yahoo.co.uk or by post to Deputy Director General, Technical Coordination DPD Headquarters, 164, GLT Road, Kolkata-108.