[R-sig-Geo] GWR Output Attributes

[Roger Bivand]

On Tue, 26 Mar 2019, James Garrett wrote:

> Dear R-Sig-Geo List,
>
> I am hoping to verify the output variables from a gwr model (package
> spgwr). I've searched through the archives and haven't been able to find
> exactly what a few are, although I have a strong guess from the package
> description:
>
> SDF a SpatialPointsDataFrame (may be gridded) or SpatialPolygonsDataFrame
> object (see package "sp") with *fit.points, weights, GWR coefficient
> estimates, Rsquared, and coefficient standard errors in its "data" slot.*

There is no need to guess. Help pages have examples. Run:

library(spgwr)
example(gwr)
str(col.gauss)
str(col.gauss$SDF)
names(col.gauss$SDF)

to examine the contents of the objects of the first run. Note that the 
rest of the example script shows why GWR is unreliable.

Don't guess, don't google or SO, just use the examples in the help pages 
actively, for example changing the formula or argument values to see what 
the arguments do. Do use alternative implementations to check your 
assumptions, such as GWmodel. Do read vignettes: vignette("GWR").

Hope this helps,

Roger


>
> Is this correct?
> sum_w = sum of the weights
> Intrc = X Intercept
> gtVI(F) = GWR coefficient estimates of the X intercept
> gwr_e = gwr residuals
> pred = Y prediction
> localR2 = local R2.
>
> I apologize if this is rudimentary. Thanks so much in advance,
>
> James
>
>

-- 
Roger Bivand
Department of Economics, Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; e-mail: Roger.Bivand using nhh.no
https://orcid.org/0000-0003-2392-6140
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