cu_sf_kde: Spatial kernel density estimate

cu_sf_kdeR Documentation

Spatial kernel density estimate

Description

A weighted or unweighted Gaussian Kernel Density estimate for point spatial data

Usage

cu_sf_kde(x, w = NULL, bw = NULL, ref, ess = NULL, mask = FALSE)

Arguments

x

sf POINT object

w

Optional values, associated with x coordinates, to be used as weights

bw

Standard deviation scale bandwidth of Gaussian Kernel, must be units of x projection.

ref

A terra SpatRaster

ess

A effective sample size to use instead of nrow(x) for determining the default bandwidth.

mask

(TRUE/FALSE) mask resulting raster if ref is provided as a SpatRaster

Details

Please note that ks methods for estimation has been reverted to the Gussian method proposed in Venables & Ripley (2002). There was not enought evendence that the Chacon & Duong (2018) multivariate method(s) for bandwidth selection and kernal estimation were suitable for spatial random fields.

Value

a terra SpatRaster class object containing kernel density estimate

Author(s)

Jeffrey S. Evans jeffrey_evans@tnc.org and Devin S. Johnson devin.johnson@noaa.gov

References

Duong, T. & Hazelton, M.L. (2005) Cross-validation bandwidth matrices for multivariate kernel density estimation. Scandinavian Journal of Statistics, 32, 485-506.

Wand, M.P. & Jones, M.C. (1994) Multivariate plug-in bandwidth selection. Computational Statistics, 9, 97-116.

Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.


dsjohnson/crawlUtils documentation built on Sept. 13, 2024, 1:34 p.m.