Hi all,
I am interesting on running random effects models in MARK but I am having some "technical troubles".
I have CMR-based data on Ural and tawny owl (1986 until 2010).
When I get to the "Variance Component Estimation" window I select "random effects", "graphical output", "numerical output" and "intercept only". I always get the error message: "error -- matrix D was found to be not positive definite. Sigma 2 = 2437.8700 (3369.0477 to 1507.2612)"
I only get this error message when retrieving (and using) the Phi(t)p(t) model. When I use any other model, I do not get this message but I cannot get the graphical output. In addition, when I add the model to the browser, the AIC is very large, and the estimates are 0 or 1.
Does anybody know how to solve this problem or have any alternative idea to run these models?
Thank you very much in advance.
Diego