In YuriNiella/RSP: Refined Shortest Paths

knitr::opts_chunk$set(
    echo = TRUE)

Index

5.1. Calculating dBBMM areas and overlaps between pairs of groups in time steps

Please be aware that The dBBMM are computationally heavy models. This means that they may kill your R session if you try to perform these calculations for very long study periods (e.g. 1 year of data across several individuals tracked). To overcome this issue we developed the function getAreaStep(), which allows RSP users to calculate the dBBMM areas for pairs of groups tracked, together with their corresponding overlapping areas (in absolute values and relative frequencies). This function currently only works with the 50% and 95% contours (RSP default), and the calculations are performed according to 1-day time steps (but can be defined using the timeframe argument). The number of individuals detected from each group of interest in each time step are also obtained.

Another issue with running the dBBMM is losing your progress when the R session dies. To avoid this, getAreaStep() will export the calculated areas to your disk by default (save = TRUE) as it goes, and you can choose the name and directory of the output file using the argument name.new. In case your computer/R dies for any reason (bad memory, power, etc.), you can always come back to where it stopped by setting the previously exported ouput file (using the name.file argument), setting another output name for the new calculations (name.new), and defining the start date from where to resume the area calculations (start.time argument). For more details, see the example in ?getAreaStep.