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st: RE: geographically weighted regression


From   "Nick Cox" <n.j.cox@durham.ac.uk>
To   <statalist@hsphsun2.harvard.edu>
Subject   st: RE: geographically weighted regression
Date   Fri, 24 Oct 2008 18:38:33 +0100

-gwr- was published in the Stata Technical Bulletin in 1998: 

STB-46  sg95  . . . . . . . . . . . . . . . Geographically weighted
regression
        (help gwr if installed) . . . . . . . . . . . . . . . . . M. S.
Pearce
        11/98   pp.20--24; STB Reprints Vol 8, pp.189--194
        applies geographically weighted regression to a dataset
        containing geographical reference points

I have not used it, but the implication that it is not well documented
is a little misleading. The article above is freely available at the
Stata website, regardless of whether you or your institution ever
subscribed. See 

http://www.stata.com/products/stb/journals/stb46.pdf

Nor is there much mystery about st_0_0_1. You can look at the code
within Stata by 

. viewsource gwr.ado 

and even without any need to be a Stata programmer see that this is the
name of the data file being used to store results. (Nowadays a temporary
file might well be used.) 

On your main point, I don't find it especially surprising that it is
slow, as the thrust of the technique is to get an idea of spatial
variability through repeated modelling, in your case thousands of times.
In addition -gwr- could be speeded up a bit, and perhaps even a lot, by
taking advantage of changes in Stata over the last decade, but that
doesn't help you unless someone does it. 

Nick 
n.j.cox@durham.ac.uk 

Helen Rosenkrantz

I am running a geographically weighted regression model in Stata with
3,019 observations and 5 variables. I am wondering if anyone might be
able to help me since I have found little guidance available online
regarding gwr in stata (aside from some information provided by the
program creator and help function). It has been processing for over 24
hours and seems to be updating an output dataset called "st_0_0_1".
Included in this mystery dataset are numbers for the 5 vars and the
constant.

Here is my syntax: gwr  depvar indvars,east( xcoo) north( ycoo)
reps(1000) test saving(eb_gwr) outfile(eb_gwr) mcsave(mc_eb)


Has anyone had success in using Stata for GWR?? Any help would be
greatly appreciated! 

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