Sources of Collection of data: Based on the data sources, data could be seen as of two types, viz., secondary data and primary data. The two can be defined as under:
(I) Primary data:
1. Those data which do not already exist in any form, and thus have to be collected for the first time from the primary source(s).
2. By their very nature, these data are fresh and first-time collected covering the whole population or a sample drawn from it.
(II) Secondary data:
1. They already exist in some form: published or unpublished in an identifiable secondary source.
2. They are, generally, available from published source(s), though not necessarily in the form actually required, e.g. Data from CSO, NSSO, RBI….
