# **3.1 Data Sources and Variable Construction**

We combine a three-round panel household survey with administrative data. The household survey includes information on some 4,000 households in 480 villages from five districts in Andhra Pradesh that were interviewed in 2004, 2006, and 2008.<sup>6</sup> This allows us to use the 2004 and 2006 household survey rounds as a preprogram baseline to obtain double and triple difference estimates of program effects.<sup>7</sup> Moreover, three of the sample districts were covered by NREGS in 2006 under phase 1, so the 2008 survey data can be used to draw inferences regarding medium-term effects of NREGS. The remaining districts were included in phases 2 and 3, so the 2008 data are indicative of short-term program effects.

The household survey includes information on demographic status, participation in casual labor markets (including NREGS), spending on food and nonfood items,<sup>8</sup> asset endowments, and investments in land. Survey information plus a qualitative exercise was used to assign households by poverty status either to the poorest of the poor, the poor, the not-so-poor or the non-poor.<sup>9</sup> Inclusion of the job card number in the 2008 survey provides a link between our household-level data and administrative records on program participation. Administrative data, available online, include job card information for all (registered) wageseeking households; muster roll information such as wage rate, total workdays, and payments for each worker; and characteristics of all NREGS works, including their completion status.

The household data allow us to use changes in nutritional intake as a measure of short-term program effects and asset endowments and land-related investment to capture medium-term effects. We measure nutritional intake by multiplying physical quantities of the more than 30 food items in the questionnaire’s consumption section with their caloric and protein content based on India’s main reference (Gopalan, Rama Shastri, and Balasubramanian 2004) to compute calories and protein consumed.<sup>10</sup> Nonfinancial assets include consumer durables, equipment, and livestock.<sup>11</sup> Consumption and assets are in per capita terms based on adult equivalent measures throughout.<sup>12</sup> Finally, we have information on whether or not a

> 6 Villages were randomly selected in these districts, and then households in these villages. The number of sampled households is 4,759 in 2004, 4,693 in 2006, and 4,533 in 2008. The attrition rate is 3.1 percent from 2004 to 2006 and 3.4 percent from 2006 to 2008. We have a total of 4,460 panel households across the three rounds.

> 7 Although the 2006 round was collected from August to October, shortly after the launch of NREGS in early 2006, contamination in 2006 is minimal, as only 29 of the 2,467 sample households with NREGS information in 2008 (all in the treatment group) actually worked under NREGS. 8 Although the survey instrument is less disaggregated than that of the NSS, it follows the overall structure used there. 9 The poorest of the poor are defined as those who can eat only when they get work and who lack shelter, proper clothing, social respect, and means to send their children to school. The poor have no land, live on daily wages, and need to send school-age children to work in times of crisis. The not-so-poor have some land, have proper shelter, send their children to public schools, are recognized in society, and have access to bank credit as well as public services. The nonpoor have more than 5 acres of land; have no problem obtaining food, shelter, and clothing; can hire laborers, send their children to private schools, use private hospitals, and lend rather than borrow money; and have considerable social status.

> 10 For fruits or vegetables where the survey includes only aggregate spending, we use the 55th round of the NSS to derive the price and caloric content of a representative basket of these consumed in Andhra Pradesh.

> 11 Asset values were measured as of December 2003 in the 2004 survey, as of June 2006 in the 2006 survey, and as of June 2008 in the 2008 survey. Financial assets were excluded due to concerns about misreporting.

> 12 The adult equivalent measures for caloric and protein consumption are obtained using nutritional requirements by sex and age as weights, that is, weights are 1.2 for adult males, 0.9 for adult females, 1.0 for adolescents (12 to 21 years), 0.8 for children aged 9 to 12, 0.7 for children aged 7 to 9, 0.6 for children aged 5 to 7, 0.5 for children aged 3 to 5, and 0.4 for children younger than 3 (Gopalan, Rami Shastri, and Balasubramanian 2004). For income and overall consumption, we assign the weight of 0.78 for anyone older than 60 or younger than 14.

8