[STATSGRASS] Re: [GRASSLIST:10737] krigging result looks weird

[Carlos "Guâno" Grohmann]

OK I did understant what you wan tme to do and why, but I didn't get how...
BTW I overlaid the vector points and the krigged map in GRASS and yes,
the artifacs position match the points position

Carlos

On 3/7/06, Roger Bivand <Roger.Bivand at nhh.no> wrote:
> On Tue, 7 Mar 2006, Edzer J. Pebesma wrote:
>
> > At the risk of being too obvious/ignorant, is the issue that kriging
> > reproduces
> > observed values where grid cell centres exactly coincide with data points?
> > A solution to that may be to shift the grid (or data) over a very small
> > distance.
>
> No, I asked Carlos to move this here because I suspected that there might
> be a direct explanation. Carlos, could you try jittering the input data
> points, would just moving them within a target 30m cell be enough, say
> within +/-15m? x+runif(*, -15, +15), y the same, and hope that both
> runif()s don't say 0?
>
> Thanks!
>
> Roger
>
> > --
> > Edzer
> >
>
> --
> Roger Bivand
> Economic Geography Section, Department of Economics, Norwegian School of
> Economics and Business Administration, Helleveien 30, N-5045 Bergen,
> Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
> e-mail: Roger.Bivand at nhh.no
>
>


--
+-----------------------------------------------------------+
              Carlos Henrique Grohmann - Guano
  Geologist M.Sc  - Doctorate Student at IGc-USP - Brazil
Linux User #89721  - carlos dot grohmann at gmail dot com
+-----------------------------------------------------------+
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