----- Original Message -----
Sent: Thursday, October 24, 2002 12:00
AM
Subject: AI-GEOSTATS: block kriging,
routines that do this, especially any in Splusor Arch-info
G'day all,
I'm relatively new to this list so if I'm asking a question that has been
recently considered sorry about that. I couldn't see any reference to an
archive on the web site so I haven't been through that if there is one.
Basically I'd like to know if theres any free-ware block kriging
routines. I've been using Arc-Info as my GIS but as we don't have
the spatial modelling module I need some additional software. If theres any
routines that are compatible with Arc-info that would be great. Failing that
some in Splus would be a close second. Failing that anything will
do.
For those that are interested I've included a brief statement on what I'm
doing with the block kriging. If anyone has any comments on the method
we're following these would be cheerfully, and gratefully, considered.
I'm involved in a project that is attempting to develop a map of past
tree density. The idea being that this will assist in developing effective
natural resource plans in NSW Australia. We're also going to construct a
current tree density map for comparison.
We've using data from the original surveys used to carve up
Australia by the Europeans. Bascially we've got the distance from
each fence cornerpost to the nearest tree, and we've used this to estimate the
tree density at that 'point' . So we've got geostatistical data with a series
of 'points' estimating density. We don't want to do ordinary kriging since
theres some issues with the density estimate (we can't really have a point
estimate of density, density requires size). Also, some of the trees are
so close to the corner post that the density estimate is way way way to big.
So we decided that block kriging would be a great way to 'average' this
problem out.
Thankyou all for your help.
Christopher G Howden
Statistical Ecologist
(Work) 02 9895
7130
(Fax) 02 9895 7867
(Mob) 0410 689
945
