mopa (version 1.0.1)

pseudoAbsences0: Pseudo-absences internal

Description

Pseudo-absence data generation at random or by k-means clustering inside a single background or a group of backgrounds (e.g. of different extent, backgroundRadius)

Usage

pseudoAbsences0(xy, background, exclusion.buffer = 0.0166, prevalence = 0.5,
  kmeans = FALSE, varstack = NULL)

Arguments

xy

Data frame or list of data frames with coordinates (each row is a point), this is, presence data

background

Matrix or list/s of matrixes with background coordinates in columns. Object derived from function backgroundGrid, OCSVMprofiling or backgroundRadius.

exclusion.buffer

value of the minimum distance to be kept between presence data and pseudo-absence data. Default is 0.0166

prevalence

Proportion of presences against absences. Default is 0.5 (equal number of presences and absences)

kmeans

Logical. If FALSE (default) pseudo-absences are generated at random. If TRUE k-means clustering of the background is done and centroids are extracted as pseudo-absences.

varstack

RasterStack of variables for to compute the k-means clustering. Used if kmeans = TRUE.

References

Iturbide, M., Bedia, J., Herrera, S., del Hierro, O., Pinto, M., Gutierrez, J.M., 2015. A framework for species distribution modelling with improved pseudo-absence generation. Ecological Modelling. DOI:10.1016/j.ecolmodel.2015.05.018.