Multi-session model fits issue

[Meidina Fitriana]

Hi Murray,

My name is Meidina, a graduate student in the master's program at Washington State University in Pullman, USA. 

I am studying the spatial ecology of the wildcats in Sumatra, with a particular focus on estimating the density of the Sumatran tiger and the Sunda clouded leopard. I have two study sites, STB and SSB. I conducted research in STB from July 2021 to July 2022, and in SSB from August 2022 to July 2023. 

At the moment, I am analyzing density using the secr package. The single-season script run smoothly, but I encountered an error with the multisession model fits. The error may have occurred in how I defined the density model, particularly after incorporating spatial covariates based on the collinearity matrix.

Regarding this matter, would you be willing to review my script and provide some feedback on what might be going wrong?

I am attaching the multi-session script for the Sumatran tiger, along with the covariate correlation matrix plot for your reference.

Thank you so much for your time and support. I look forward to hearing your thoughts.

Best regards,

Meidina

[Murray Efford]

On a quick scan of your code I don't see any problem. I am reluctant to go further because that would require installing packages I don't use, you do not specify the problem, and you do not provide all the (mask) data. I also suspect that you are trying to fit models way beyond what is feasible with the modest samples you have. Please address the group, not me personally: I'm always hopeful that others might contribute.

Sorry to sound so negative -  I respect the effort you've put in,  your R code is tidy, and the data look interesting. Perhaps just start with one simple multi-session model.

Murray