“For effective decisionmaking, policymakers and program managers often need detailed information about the welfare of the population, including knowledge about
which specific areas are most affected by poverty and undernutrition. Household sample
surveys are an important source of information, yet because the typical sample size is
only a few thousand observations, the information is only useful for inferences at high
levels of aggregation, such as the nation or large regional units. In contrast, data sources
with wider coverage, such as national censuses, rarely capture detailed information on
welfare levels. Recently small-area estimation techniques have been applied to the study of poverty to produce estimates of poverty, or poverty maps, for small geographic units.”
