hinge: Maxent feature classes

In mrmaxent/maxnet: Fitting 'Maxent' Species Distribution Models with 'glmnet'

Maxent feature classes

Description

Create and evaluate Maxent's feature classes.

These functions are typically called by model.matrix rather than directly by a user.

hinge creates 2*nknots-2 hinge features, half with min=min(x) and half with max=max(x), and knots evenly spaced between min(x) and max(x). A hinge feature h(min,knot) or h(knot,max) is 0 if the predictor is below the first argument, 1 if the predictor is above the second argument, and linearly interpolated inbetween.

A threshold feature is 1 if the predictor is above the knot, 0 otherwise.

A categorical feature is 1 if the predictor matches the category and 0 otherwise.

Usage

categorical(x)

hinge(x, nknots = 50)

thresholds(x, nknots = 50)

Arguments

x	a predictor: a factor for categorical, otherwise numeric
nknots	number of knots

Value

hinge, threshold and categorical return a matrix with a column for each feature of the specified type.

Author(s)

Steve Phillips

Examples

## Not run: 
  library(maxnet)
  data(bradypus)
  hinge(bradypus$tmp6190_ann,nknots=10)
  categorical(bradypus$ecoreg)
 
## End(Not run)

mrmaxent/maxnet documentation built on Jan. 12, 2023, 8:20 a.m.