Capture recapture for only two visit assuming a open population model
In a classic closed population model, you can estimate population size with k=2 (where k is the number of events) but it's impossible to separate survival from recapture probability.



Seeing this formula you could expect to be able to estimate recapture probability dividing R by S but it would be an error since S = M*survival (ø) *probability of recapture (p) . Therefore it's imposible to separate p from ø when k&lt;2.

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