capture–tag–recapture sampling
a method of sampling that is used to estimate population size. For example, to estimate the number of fish in a lake, a random sample of fish (e.g., 100) would be drawn and tagged, then returned to the lake. The lake would be resampled, and the results (i.e., the fraction of tagged fish in the new sample) would be used to estimate the total number of fish in the lake. Also called capture–recapture sampling; mark-and-recapture sampling.