threshold: Find a threshold

In predicts: Spatial Prediction Tools

Find a threshold

Description

Find a threshold (cut-off) to transform model predictions (probabilities, distances, or similar values) to a binary score (presence or absence).

Usage

## S4 method for signature 'paModelEvaluation'
threshold(x)

Arguments

x	paModelEvaluation object (see pa_evaluate

Value

data.frame with the following columns:

kappa: the threshold at which kappa is highest ("max kappa")

spec_sens: the threshold at which the sum of the sensitivity (true positive rate) and specificity (true negative rate) is highest

no_omission: the highest threshold at which there is no omission

prevalence: modeled prevalence is closest to observed prevalence

equal_sens_spec: equal sensitivity and specificity

Author(s)

Robert J. Hijmans and Diego Nieto-Lugilde

See Also

pa_evaluate

Examples

## See ?maxent for an example with real data.
# this is a contrived example:
# p has the predicted values for 50 known cases (locations)
# with presence of the phenomenon (species)
p <- rnorm(50, mean=0.7, sd=0.3)
# b has the predicted values for 50 background locations (or absence)
a <- rnorm(50, mean=0.4, sd=0.4)
e <- pa_evaluate(p=p, a=a)

threshold(e)

predicts documentation built on Oct. 7, 2024, 9:06 a.m.