Simulations biased high

[sixtystrat]

I am running a bunch of simulations using trap clusters to estimate bear densities. In my sparser trap configurations, the estimates of D seem to be biased high. I was expecting higher SEs but not bias. What is the reason for that?

Thanks!
Joe

[murray.efford]

When trap clusters are too small, recaptures within the cluster are inadequate to document the full extent of movements. The result (at an intuitive level) is that the observed individuals are attributed to a sampling region that is too small, and density is estimated high. See e.g. simulations in Tobler and Powell Biol Cons 2013 Fig. 2 and Efford Ecology 2011 Table 3.
Murray

[sixtystrat]

That makes sense. My 3x3 trap clusters were performing better than the 2x2 clusters. Thanks Murray.