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We are using openCR to estimate vital rates for elk but I had a question about the detection function for the PLBsecrl model. What detection function does openCR use? lambda_0 suggests a count model, not a proximity model, but looking at the documentation, it just lists lambda_0 as the detection function intercept using a log link. But I thought that the only way a log link works for proximity data is if you use a hazard half normal. So, is that what openCR is using or does it use a regular half normal with a log link somehow?
Thanks!
Joe

Hi Joe

I think you're overthinking this. ?openCR.fit shows c("HHN", "HHR", "HEX", "HAN", "HCG", "HVP", "HPX") as options for detectfn, and further on "Spatial models use one of the hazard-based detection functions (see detectfn) and require data from independent point detectors (secr detector types ‘multi’, ‘proximity’ or ‘count’)". The default is HHN, with default link 'log'. The hazard parameterisation works for any of the detector types.

Perhaps you're tripping up over the fact that openCR does not implement the non-hazard, probability "regular half-normal".

Murray

I think that is what I need. Thanks Murray!