generate_pseudo_absences: Generate Pseudo-Absence Points Using Different Methods Based...

In glossa: User-Friendly 'shiny' App for Bayesian Species Distribution Models

Generate Pseudo-Absence Points Using Different Methods Based on Presence Points, Covariates, and Study Area Polygon

Description

Wrapper function for pseudo-absence generation methods, such as background random points, target-group, and using buffer area.

Usage

generate_pseudo_absences(
  method = c("random", "target_group", "buffer_out"),
  presences,
  raster_stack,
  predictor_variables,
  study_area = NULL,
  target_group_points = NULL,
  coords = c("decimalLongitude", "decimalLatitude"),
  pa_buffer_distance = 0.5,
  ratio = 1,
  attempts = 100,
  seed = NULL
)

Arguments

method	Character; one of "random", "target_group", or "buffer_out".
presences	Data frame of presence points with coordinates and timestamp.
raster_stack	SpatRaster of covariates.
predictor_variables	Character vector of selected predictors.
study_area	Optional sf polygon (used for clipping).
target_group_points	Optional data frame of sampling points (for target-group).
coords	Vector of coordinate column names.
pa_buffer_distance	Numeric; buffer radius in degrees around each presence. Default is 0.5.
ratio	Ratio of pseudo-absences to presences.
attempts	Max attempts to fulfill sample size.
seed	Optional seed for reproducibility.

Value

A data frame of pseudo-absence points (pa = 0) with covariates.

glossa documentation built on June 8, 2025, 1:20 p.m.