# **<mark>3. Assessing differences in sampling and survey design</mark>**

In this paper, we examine eight aspects of sampling and survey design that are directly related to poverty measurement. These include the following: (i) sampling design; (ii) monetary welfare measure; (iii) food consumption questionnaire and data collection methods; (iv) self-production and meals outside home; (v) non-food durables; (vi) durables; (vii) housing expenditures; and (viii) health and education expenditures.

# _Sampling design_

Table 4 presents a summary of the sampling design for each of the eight countries in South Asia. With few exceptions, household-level surveys used to measure poverty in the region are nationally representative. Afghanistan, Bangladesh and India do not survey all the regions within the borders of their respective countries. In 2011/12, Afghanistan excluded the provinces of Helmand and Khost from the survey for poverty measurement.<sup>10</sup> These two provinces had an estimated population of 864,600 (Helmand) and 537,800 (Khost) in 2012.<sup>11</sup> The total population of Afghanistan in 2012 is about 24.8 million, so these two provinces combined represent around 5.65 percent of the population. Bangladesh did not traditionally include the slum population as part of the sampling frame for the HIES until 2016/17. According to the Bangladesh Bureau of Statistics Census of Slum and Floating Population collected in 2012, the slum population is about 2.22 million, which corresponds to 5.5 percent of the total population in urban areas.<sup>12</sup> The NSS 68<sup>th</sup> round from India excluded from its sampling frame the remote areas of Nagaland, and Andaman and Nicobar Islands. The population of Andaman and Nicobar Islands is 380,000, while that of Nagaland is 1.98 million. Given that India had a population of 1.247 billion in 2011, this makes the proportion of individuals excluded from the survey reach just 0.2 percent of the total population.

Sample sizes vary widely across household-level surveys used to measure poverty. Maldives surveys about 1,800 households, while India surveys over 100,000. The range of individuals covered by these household surveys varies from 11,500 in Maldives to over 464,000 in India. This translates to a wide span of sampling ratio – from 0.04 percent in Bangladesh to 7 percent in Bhutan.

# _Monetary welfare measure_

Countries in the region use broadly similar methods to measure per capita consumption aggregates. All countries in South Asia use consumption rather than income to measure poverty. To estimate international poverty, total household consumption is divided by the number of individuals in the household to get a per capita estimate. This matches the methodology used by all countries in the region to estimate national per capita consumption aggregates, except for Pakistan. Pakistan uses

> 10 The provinces of Helmand and Khost were included in the household survey but these are not used to estimate poverty as there are issues with the consumption data quality in these two provinces.

> 11 Central Statistics Organization (2017).

> 12 There is a long-standing debate in Bangladesh about the size of the slum population. The Census and Mapping of Slums collected by the Center for Urban Studies in 2015 estimated that 35.2 percent of the urban population in Bangladesh lived in slums, while the UN Habitat Global Report on Human Settlements (2013) estimated the proportion or urban slum dwellers at 61.6 percent for 2009.

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