rangerarity: Range rarity metric of endemism

View source: R/ranges.R

rangerarityR Documentation

Range rarity metric of endemism

Description

The function calculates the cumulated range rarity for every geographic cell given an occurrence table

Usage

rangerarity(dat, tax, loc, fine = NULL)

Arguments

dat

data.frame or RasterStack The occurrence table.

tax

character Variable name of the taxon names.

loc

character Variable name of the locality information (e.g. geographic cells). Range rarity will be output for every entry in this column.

fine

character Variable name of the basic geographic information (optional) that is clustered to coarser units (in loc).

Details

The metric was originally impelmented by Selig et al., 2014 (Plos ONE). For every cell or locality (loc argument), the function sums up the inverse occupancy (1/occupancy) of every taxon that occurrs there. If available, the function will weigh each of these taxon/locality specific values by a fraction. As in Selig et al. (2014), this is the proportion of finer-scale occurrence-points (e.g. coordinates) in the locality (cell) compared to the maximum observed number of fine-scale occurrences in that particular locality (cell). In other words, entries in loc cluster entries in fine. The weights will be the number a taxon has compared to the maximum number observed in the whole dataset.


adamkocsis/obigeo documentation built on Oct. 14, 2024, 8:46 a.m.