GWR Output Attributes

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

GWR Output Attributes

James Garrett
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.*

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

--

*James Garrett*

Clemson University

Graduate Student, Forest Resources

School of Agricultural, Forest, and Environmental Sciences

Phone (334)-790-2483

Advisor: Dr. Skip Van Bloem

        [[alternative HTML version deleted]]

_______________________________________________
R-sig-Geo mailing list
[hidden email]
https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Reply | Threaded
Open this post in threaded view
|

Re: GWR Output Attributes

Roger Bivand
Administrator
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: [hidden email]
https://orcid.org/0000-0003-2392-6140
https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en

_______________________________________________
R-sig-Geo mailing list
[hidden email]
https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Roger Bivand
Department of Economics
Norwegian School of Economics
Helleveien 30
N-5045 Bergen, Norway
Reply | Threaded
Open this post in threaded view
|

Re: GWR Output Attributes

Roger Bivand
Administrator
On Tue, 26 Mar 2019, Roger Bivand wrote:

> 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.

I've just used pkgdown to commit the processed help pages of spgwr to
R-Forge:

http://rspatial.r-forge.r-project.org/spgwr/reference/gwr.html#examples

is the rendered version of running example(gwr) yourself, and is less
effective because you can't play with the output.

Roger

>
> 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: [hidden email]
https://orcid.org/0000-0003-2392-6140
https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en

_______________________________________________
R-sig-Geo mailing list
[hidden email]
https://stat.ethz.ch/mailman/listinfo/r-sig-geo
Roger Bivand
Department of Economics
Norwegian School of Economics
Helleveien 30
N-5045 Bergen, Norway