Incomplete detection in enumeration surveys: Whither distance sampling?

Welsh, A.H. (2002) Incomplete detection in enumeration surveys: Whither distance sampling? Australian & New Zealand Journal of Statistics, 44 (1), 13-22. (doi:10.1111/1467-842X.00204).

Record type: Article

Abstract

We consider the problem of undercount or incomplete detection in enumeration surveys which are intended to estimate population counts or population abundance. The problem is widespread in ecology but also occurs in other surveys: The census undercount is a well-known example of the problem. After framing the problem in a general context, we focus on line transect sampling and the distance sampling methodology which has been widely applied in surveys of ecological populations. We describe distance sampling data and present a graphical derivation of the distance sampling estimator. Our graphical analysis leads to a new expression for the distance sampling estimator which gives useful insights into the nature of the estimator. We discuss the uniformity assumption on which distance sampling depends and describe the properties of the distance sampling estimator when uniformity does not hold. We then explore the relationship between this and other evaluations of distance sampling. We mention briefly some statistical ideas for treating the general incomplete detection problem and conclude with some reflections on general insights arising from the research.

This record has no associated files available for download.