What the debate on NSS population counts missed out

livemint.com:

One of independent India’s early achievements was to set up a large-scale household survey system. The National Sample Survey (NSS) set up in 1950 and the Sample Registration System initiated in the 1960s inspired similar experiments all over the world. Since the late 1970s, innovation in the official statistical system has slowed down even as the structure of the Indian economy began changing rapidly.

The 1990s brought budget cuts and ill-considered administrative changes, creating a massive manpower crisis. Political pressures on the NSS mounted even as it struggled to deliver the new demands being made on it. The Rangarajan Commission report of 2001 made several recommendations to help it regain its edge and to insulate it from political interference.

Successive governments have implemented those recommendations in a half-hearted manner. The National Statistical Commission (NSC) was set up in the mid-2000s to regulate statistical activities, but it has not been provided statutory backing till now. In spite of its limited powers, the NSC has been able to intervene on some critical issues.

One such issue pertains to the impaired sampling frame of the NSS. The NSC’s role in modernizing the NSS sampling frame has been ignored by both defenders and critics of the NSS in the recent debate on survey quality in India. An under-estimation of our urban population in NSS surveys has consistently figured in NSC meetings ever since it was set up, official records show.

In the early years of the NSS, the census was used as a sampling frame to pick samples in both rural and urban areas. After a few rounds, it became clear that the census database on urban settlements was inadequate. Given the fluid nature of many urban settlements