Dear all I am working with count data and I want to assess whether the centre of gravity of the population (centroid or mean latitude?) has change over time, indicating some redistribution or shift ongoing. To simplify, let's say that I have ca. 2000 sites censused in two consecutive years (same sites censused both years - all sites) and the abundance (count) of the species registered.
I first thought about doing a kernelUD (package adehabitatHR) but apparently this only takes into account the location of the sites to calculate the kernel and then the centroids. Thus, since I have the exact same sites in both years, the centroids for year 1 and year 2 are the same. In my case, what I would like to do is to calculate that centroid but taking into account the counts, because a site that had 3 individuals in both years can't have the same weight than a site that hosted 3000 individuals when calculating the centroids. So, what I would like to have is the centroid (or centre of gravity) of the counts not of the sites surveyed (which is what adehabitatHR does,a s far as I understood). Do you have any suggestions which package other than adehabitatXX to use for this purpose? Or if this can be done with adehabitat? Thank you very much for your help. Diego -- *Diego Pavón Jordán* *Finnish Museum of Natural History* *PO BOX 17 * *Helsinki. Finland* *0445061210https://tuhat.halvi.helsinki.fi/portal/en/persons/diego-pavon-jordan%288d5db37c-eddd-4fca-92cd-9c9956a42b4a%29.html <https://tuhat.halvi.helsinki.fi/portal/en/persons/diego-pavon-jordan%288d5db37c-eddd-4fca-92cd-9c9956a42b4a%29.html>http://www.linkedin.com/profile/view?id=170617924&trk=nav_responsive_tab_profile <http://www.linkedin.com/profile/view?id=170617924&trk=nav_responsive_tab_profile>https://helsinki.academia.edu/DiegoPavon <https://helsinki.academia.edu/DiegoPavon>* [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
