India - Annual Survey of Industries: 2012-13

The sampling design adopted in ASI has undergone considerable changes from time to time, taking into account the technical and other requirements. The earlier sampling design had been adopted from ASI 2007-08 to ASI 2011-12. From ASI 2012-13, a new sampling design has been adopted following the recommendation of Dr. S. L.Shetty Committee and approved by the SCIS subsequently. According to the new sampling design, all the factories in the updated frame are divided into two sectors, viz., Census and Sample.

Census Sector: Census Sector consists of the following units:
a) All industrial units belonging to the six less industrially developed states/ UT's viz.Manipur, Meghalaya, Nagaland, Sikkim, Tripura and Andaman & Nicobar Islands.
b) For the rest of the twenty-six states/ UT's., (i) units having 100 or more employees, and (ii) all factories covered under Joint Returns.
c) After excluding the Census Sector units as defined in paragraphs a) and b) above, the strata will be formed at State × District × Sector × 4-digit of NIC-2008 level. Sectors are (i) Bidi, (ii) Manufacturing and (iii) Electricity. All units belonging to the strata (i.e., formed on the basis of units in State by District by Sector by 4-digit of NIC-08) having less than or equal to 4 units are also considered as Census Sector units.

Sample Sector
a) Then factories, in each stratum, are arranged in order of their number of employees. Finally, the sample will be drawn circular systematically in the form of four
independent sub-samples considering an overall sampling fraction, say, between 16% to 20%, depending upon the availability of resources of FOD/State. An even number of units with a minimum of 4 units are selected and evenly distributed in four subsamples. It may be noted that in the formation of stratum, the sectors are taken as (i) Bidi, (ii) Manufacturing and (iii) Electricity. Moreover, each of the 4 sub-samples from a particular stratum may not have equal number of units.
b) Out of these four sub-samples, two, preferably the odd ones, will be given to FOD, NSSO and the remaining two will be given to State/UT for data collection. Thus if four sub-samples SS1, SS2, SS3 and SS4 are formed in each stratum, the sub-samples SS1 and SS3 will be surveyed by NSSO, FOD, and the sub-samples SS2 and SS4 will be surveyed by State/ UT.
c) The entire units under the Census scheme plus all the units belonging to the two subsamples meant for FOD (i.e., sub-samples SS1 and SS3) may be treated as the Central sample.

The sampling design adopted in ASI has undergone considerable changes from time to time, taking into account the technical and other requirements. The present sampling design has been adopted from ASI 2007-08. All the factories in the updated frame are divided into two sectors, viz., Census and Sample.

WGT (Multiplier Factor) is the weighing variable from Block A : Identification Block.
For Census data WGT has been given weight as 1.