findres: Choose spatial resolution for analysis

In ppmlasso: Point Process Models with LASSO Penalties

Description

This function produces a plot to choose the optimal spatial resolution for analysis. A point process model is calculated for each nominated spatial resolution and the log-likelihood of all fitted models are plotted against the spatial resolutions.

Usage

findres(scales, lambda = 0, coord = c("X", "Y"), sp.xy, env.grid, formula, ...)

Arguments

scales	A vector of spatial resolutions for which to produce the plot.
lambda	The LASSO penalty for each fitted spatial resolution. This should be a single value such that only one point process model is computed for each spatial resolution.
coord	A vector containing the names of the longitude and latitude coordinates, used by env.var.
sp.xy	A matrix of species locations containing at least one column representing longitude and one column representing latitude, as in ppmlasso.
env.grid	The geo-referenced matrix of environmental grids, as in ppmlasso.
formula	The formula of the fitted model, as in ppmlasso.
...	Further arguments passed to ppmlasso.

Value

A plot of log-likelihood versus spatial resolution.

Author(s)

Ian W. Renner

Examples

data(BlueMountains)
sub.env = BlueMountains$env[BlueMountains$env$Y > 6270 & BlueMountains$env$X > 300,]
sub.euc = BlueMountains$eucalypt[BlueMountains$eucalypt$Y > 6270 & BlueMountains$eucalypt$X > 300,]
scales = c(0.5, 1, 2, 4, 8, 16)
ppm.form = ~ poly(FC, TMP_MIN, TMP_MAX, RAIN_ANN, degree=2)
findres(scales, formula = ppm.form, sp.xy = sub.euc, env.grid = sub.env)

ppmlasso documentation built on May 2, 2019, 8:20 a.m.