On Tue, 5 Jun 2007, Patrick Wang wrote: > Hi, I found kde2d in the MASS packages return densities for the bivariate > random varaibles. > > I donot understand why each element of density Z is a 2*2 matrix. > Why it is not a number. > > For example, a bivariate normula distribution given (x, y) will return a > number, the density, not a matrix.
I think you were asking these questions last week: library(mvtnorm) ?dmvnorm not 2D kernel *density* (the word is perhaps overloaded). However, kde2d() *is* a 2D density(), so maybe you need to consider what you are looking for. > > Thanks > Pat > > > > Hi all: > > > > I can use the density() function to get the kernel density for given > > observed data X with bandwidth. > > > > Is there a function in R that can take in two dimensional data(x, y) and > > return a joint density based > > on the bandwidth. Do I need to provide bandwith for x and then for y? > > > > Is the GRASS package > > kde2d.G(x, y, h, G, reverse=reverse(G)) > > > > provide such function? > > > > Thanks > > pat > > > > ______________________________________________ > > R-help@stat.math.ethz.ch mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > > http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- Roger Bivand Economic Geography Section, Department of Economics, Norwegian School of Economics and Business Administration, Helleveien 30, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 e-mail: [EMAIL PROTECTED] ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.