confidence intervals for abundance

questions concerning anlysis/theory using program DENSITY and R package secr. Focus on spatially-explicit analysis.

confidence intervals for abundance

Postby Ulrike » Sun Sep 22, 2019 3:06 pm


So far, I have derived the confidence intervals for abundance from the CI's for the density, which I get with the derived function.
However, if a specific number of animals, let's say n_obs have been captured in an area, then I believe the lower limit of the confidence interval should be at least as large as n_obs, since this is the number which definetely exists in the study area (?)
However, if I derive this from the density lower CI limit, then the lower limit of the CI for abundance is lower then n_obs.
Does anyone have an opionion how to deal with this?
Thanks and best regards, Ulrike
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Re: confidence intervals for abundance

Postby murray.efford » Mon Sep 23, 2019 8:17 pm

Have you looked at region.N? The number observed is only a lower bound of N given a binomial model for n, not for the default Poisson model. Also, N is often a poorly defined parameter - is your study area bounded in some way?
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