title: Sampling of subpopulations in two-stage surveys.
abstract: Many health and other surveys aim to produce statistics on small subpopulations, such as specific ethnic groups or the indigenous population of a country. In most countries, there is no reliable sampling frame of the subpopulations of interest, hence it is necessary to sample from the general population, which can be very expensive. A range of issues and strategies for sampling rare subpopulations is reviewed. The most common approaches in practice are the use of a large screening sample, and disproportionate sampling by strata. Optimal sample designs have been derived for the case of one-stage sampling, but most household interview surveys use two or more stages of selection. This paper develops optimal designs for two-stage sampling, where there is auxiliary information on subpopulation numbers for each primary sampling unit. Various alternative designs are evaluated using a simulated population derived from the New Zealand Census.
authors.affiliation: Centre for Statistical and Survey Methodology, School of Mathematics and Applied Statistics, University of Wollongong, NSW 2522, Australia. rclark@uow.edu.au
authors.forename: Robert Graham
authors.initials: RG
authors.lastname: Clark
mesh_terms: D000328:Adult; D003198:Computer Simulation; D003625:Data Collection / Q000379:methods*; D003627:Data Interpretation, Statistical; D006801:Humans; D044382:Population Groups