Category:Examples of Capture-Recapture Sampling

This category contains examples of Capture-Recapture Sampling.

Capture-recapture sampling is a statistical technique for estimating the size of animal populations.

In its simplest form, a sample of $n_1$ animals is captured, and each one tagged and released.

A second sample of $n_2$ animals is captured at a later date, and the number $m$ of animals which were tagged in the first round is noted.

If the unknown population size is $N$ and any animal is equally likely to be captured, the proportion $\dfrac m {n_2}$ of tagged to untagged animals is a reasonable estimate of the unknown proportion $\dfrac {n_1} N$ of tagged animals to the whole population.

Hence our estimate $N^*$ of $N$ can be calculated as:

$N^* = \dfrac {n_1 n_1} N$

provided $m \ne 0$.