mkde2Dgrid {mkde}R Documentation

Movement-based kernel density estimate (MKDE) in 2D using Rcpp

Description

Provides a function for 2-dimensional MKDEs.

Usage

mkde2Dgrid(mkde.obj, move.dat, t.step, d.thresh)	

Arguments

mkde.obj

A 2D or 2.5D MKDE object

move.dat

A move data object

t.step

An integration time step

d.thresh

A kernel density threshold

Details

This is lower-level function that call the C++ function. for estimating the movement-based density in 2D. In practice, users should call initializeDensity.
The argument d.thresh is a univariate probability density beyond which the kernel contribution to the overall MKDE is assumed to be negligible. Usually this is set at a very small value and is used to prevent calculations from being performed in cells to which the kernel makes a negligible contribution.

Value

An array whose elements are the estimated utilization probabilities for each cell.

Author(s)

Jeff A. Tracey, PhD
USGS Western Ecological Research Center, San Diego Field Station
jatracey@usgs.gov
James Sheppard, PhD
San Diego Zoo Institute for Conservation Research
jsheppard@sandiegozoo.org
Robert Sinkovits, PhD
San Diego Supercomputer Center
sinkovit@sdsc.edu
Glenn Lockwood, PhD
San Diego Supercomputer Center
glock@sdsc.edu
Jun Zhu, PhD
University of Wisconsin-Madison
jzhu@stat.wisc.edu

Examples

library(raster)
data(panda)
mv.dat <- initializeMovementData(panda$time, panda$x,
panda$y, t.max=185.0, sig2obs=25.0)
mv.dat <- initializeMovementData(panda$time, panda$x, panda$y, 
sig2obs=25.0, t.max=185.0)

data(pandadem)
cell.sz <- mean(res(pandadem))
ext <- extent(pandadem)
nx <- ncol(pandadem)
ny <- nrow(pandadem)
mkde.obj <- initializeMKDE2D(ext@xmin, cell.sz, nx, ext@ymin, cell.sz, ny)

res <- mkde2Dgrid(mkde.obj, mv.dat, 10.0, 1e-20)

[Package mkde version 0.1 Index]