n hat in a closed population

[jlat]

I am using a robust desing, closed population model to estimate the population size of my study species. When I look at the output I see that the N hat given by the model is exact to the number of distinct individuals caught in each session. I assume that this is not right.
I am unsure where I am going wrong, nay advice?
thanks

[cooch]

I am using a robust desing, closed population model to estimate the population size of my study species. When I look at the output I see that the N hat given by the model is exact to the number of distinct individuals caught in each session. I assume that this is not right.
I am unsure where I am going wrong, nay advice?
thanks

Presumably you've read the 'closed population estimation' chapter? If not, you should start there.

[jlat]

I know constraints need to be put upon p and c, but when trying to fix the parameters I get no option for c. so I adjusted the model so that c=p. Is this sufficient for a robust model?

[Todd]

In the most perameterized model in your robust design you should have a p for every secondary session. You should have a c for all but the first secondary session in each primary period.

You must constrain the last p of each session = to the session before it at a minimum to have a real N estimate. I don't know that you have to do anything to the c.

If you are modeling p as constant within the secondary session you shouldn't have a problem with your N estimate.