Help with the Barrier Model

[Marius Clabaux]

Hello INLA community, 

I have been working on sightings data of killer whales and I have been setting a model to study the distribution of killer whales according to different environmental covariates such as temperature or salinity. The dependent variable is the presence (1) or absence (0) of killer whale.

I Attached to the message several files : 

I - The R code of the model (including the mesh construction)

IV - Data: sightings & coast lines

The problems I have are the following: 

(1) The results I get from the non-stationary model which includes the barrier (such as the spatial field, theta1, theta2 and all other parameters values) do not change whatever the inputs of the model (such as the priors, the mesh, the amount of covariates).

(2) In my model including the barrier, there is no spatial effect, and it seems that all the variability in the distribution of the Killer whales is explained by the environmental covariates (the mean spatial field is very very low), which does not seems coherent.

Thank you very much for your help 

I stay available for any further information,

The very best,

Marius