spatial statistics (Was: S-plus and Grass)

[W. Fredrick Limp]

Statsci has just announced a new "add on" to Splus 3.3 -- it does include 
a number of spatial stats. Statsci has had Noel Cressie working with them 
on these.. check them out...

On Mon, 17 Jul 1995, James Darrell McCauley wrote:

> Gillian Bowser (gillian at rmro.nps.gov) writes on 17 July 1995:
> [...]
> >databases, I cannot for the life of me, figure out why they don't cover
> >spatial statistics, autocorrelation, Moran's Index, kriging, ansiotrophy,
> >etc.etc.etc.etc...
> 
> Because it's not a *spatial* statistics package...
> 
> FWIW, you can calculate Moran's I and the Geary Ratio (plus their
> standard errors) using v.autocorr (on a triangulation of sites from
> s.geom). It will also spit out a W (connectivity) matrix.
> 
> Quadrat count statistics can be calculated using s.qcount,
> including:
>   Fisher el al. (1922) Relative Variance,
>   David & Moore (1954) Index of Cluster Size,
>   Douglas (1975) Index of Cluster Frequency,
>   Lloyd (1967) "mean crowding",
>   Lloyd (1967) Index of patchiness, and
>   Morisita's (1959) I (variability b/n patches)
> (see Cressie, chapter 9)
> 
> Semivariogram modeling is possible with s.sv, m.svfit, and g.gnuplot
> (no nested structures, sorry).
> 
> Plus there's some other statistical software for sites available:
> s.univar, s.probplt, and s.normal (which includes a dozen or so
> different tests of (log)normality and other alternatives).
> 
> Most of these programs are available at:
>   ftp://pasture.ecn.purdue.edu/pub/mccauley/grass
> See also the tutorials
>   ftp://pasture.ecn.purdue.edu/pub/mccauley/grass/tutorials
> and 
>   http://soils.ecn.purdue.edu/~mccauley/cdhc/
> 
> I disagree with the philosoply of one- and two-way links to stat
> packages.  These types of functions should be available *in* GIS
> packages, not in some third party program (free or otherwise). It's
> great that S-plus may become linked to GRASS (as it is with ARC/INFO),
> but I see these types of solutions as quick fixes. Why can't we
> include this functionality *in* GRASS?  Sure keeps the price
> down... :)
> 
> So, with all of that said, what other types of programs would you like
> to see? (I'm not committing myself but just getting ideas for my
> rainy-day hobby list :) If you can include a pointer to a public
> domain src for this, please do. It significantly speeds up development.
> 
> Make sure that the methods suggested make sense for spatial
> data. Remember Tober's first law ("everything is related to everything
> else, but near things are more related than distant things") and the
> assumption of independence by most traditional (non-spatial) methods.
> 
> Also FWIW, here's an interesting article (which I don't fully 
> agree with, but still worth mentioning):
> 
> @Article{ anselin93,
>   author =     "Luc Anselin and Rustin F. Dodson and Sheri Hudak",
>   title =      "Linking {GIS} and Spatial Data Anlysis in Practice",
>   journal =    "Geographic Systems",
>   year =       "1993",
>   volume =     "1",
>   number =     "1",
>   pages =      "3-23"
> }
> 
> If you need spatial statistics ASAP and can't wait for recreational
> programmers, you might check into SPACESTAT. It apparently has links to
> ARC/INFO, IDRISI, OSU-MAP, and generic raster files (does this mean
> GRASS?) See http://www.ncgia.ucsb.edu/pubs/software.html
> 
> Regards,
> Darrell
> -- 
> James Darrell McCauley, PhD           http://soils.ecn.purdue.edu/~mccauley/
> Agricultural & Biological Engineering mccauley at ecn.purdue.edu
> Purdue University                     tel: 317.494.1198 fax: 317.496.1115
> 

W. Fredrick Limp,   Director and Professor       FAX: (501) 575-5218
CAST, Center for Advanced Spatial Technologies   TEL: (501) 575-6159     
12 Ozark Hall, U of Ark., Fayetteville AR 72701   fred at cast.uark.edu 
Opinions expressed here are mine, at least I think they are.