Reference Work Entry

International Encyclopedia of Statistical Science

pp 398-400

Date:

Distance Sampling

  • Tiago A. MarquesAffiliated withUniversity of St Andrews
  • , Stephen T. Buckland BorchersAffiliated withUniversity of St Andrews
  • , David L. BorchersAffiliated withUniversity of St Andrews
  • , Eric G. RexstadAffiliated withUniversity of St Andrews
  • , Len ThomasAffiliated withUniversity of St Andrews

Distance sampling is a widely used methodology for estimating animal density or abundance. Its name derives from the fact that the information used for inference are the recorded distances to objects of interest, usually animals, obtained by surveying lines or points. The methods are also particularly suited to plants or immotile objects, as the assumptions involved (see below for details) are more easily met. In the case of lines the perpendicular distances to detected animals are recorded, while in the case of points the radial distances from the point to detected animals are recorded. A key underlying concept is the detection function, usually denoted g(y) (here y represents either a perpendicular distance from the line or a radial distance from the point). This represents the probability of detecting an animal of interest, given that it is at a distance y from the transect. This function is closely related to the probability density function (pdf) of the detected distances, f(y), a ...

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