A numerical comparison between sequential tagging and sequential recapture

This paper investigates by means of numerical solutions two experimental techniques, tagging and recapture, for sequential estimation of the size of a population. It is found that the choice between them depends critically on assumptions made about the sampling cost when sampling without replacement. If this is a constant amount per item sampled, then recapture is clearly preferable to tagging, while if it increases as the number of items remaining to be sampled diminishes then the reverse is true.