occ_virtual_species: Occurrence dataset of a virtual species

In itsdm: Isolation Forest-Based Presence-Only Species Distribution Modeling

Occurrence dataset of a virtual species

Description

A pseudo presence-absence occurrence dataset of a virtual species made by package virtualspecies.

Usage

occ_virtual_species

Format

A data.frame with 300 rows and 2 fields

x

(numeric) The x coordinates of the records in WGS84 geographic coordinate system

y

(numeric) The y coordinates of the records in WGS84 geographic coordinate system

observation

(numeric) The observations of presence and absence.

usage

(character) The usage of the occurrences, either be "train" as training set, or "eval" as test set.

Details

The environmental niche of the virtual species is made by defining its response functions to annual temperature and annual precipitation in mainland Africa. The response function of annual temperature is normal distribution with mean = 22 and standard deviation = 5. The response function of annual precipitation is normal distribution with mean = 1000 and standard deviation = 200. Then the suitability is convert to presence-absence map by logistic conversion with beta = 0.7, alpha = -0.05, and species prevalence = 0.27. Finally 500 presence-absence points are sampled across the whole region. Then these points were randomly split into train (0.7) and test set (0.3).

Source

virtualspecies

itsdm documentation built on July 9, 2023, 6:45 p.m.