Single projection for multitude of individuals (large area)

[Storm Crews]

Hello, hope all are well.

I am trying to assess pairwise overlap for AKDEs of ~50 individuals whose locations are stratified west-east over an area roughly a few hundred miles across. I see that when fitting telemetry objects, ctmm will automatically assign a custom tpeqd projection on an individual basis. Ideally I would then fit the ctmm models and use these within the akde function to get everything on the same grid to finally assess overlap. However, given that each individual is using a slightly different projection, this fails at the akde step. Of course, I can use the projection() function to reassign individual projections to be identical, but I do have some concerns on the possible distortion incurred given the large area my data covers.

My question is whether or not full re-assignment to one of the tpeqd projections for all individuals is the best approach here or if there is a more sensible way to go about this. I would use UTM but my understanding is that ctmm works best with tpeqd projections. Any thoughts on this matter are greatly appreciated! 

Best,

Storm Crews

[Christen Fleming]

Hi Storm,

You can safely use UTM if your data is within the UTM zone. The default projections are more centered on the data and should be more accurate, especially if you straddle UTM zones.

Best,

Chris

[Storm Crews]

Thank you kindly, Chris! Your response is very much appreciated.

Best,

Storm Crews