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

[Carlos "Guâno" Grohmann]

And Yes, the artifacts are present in R.

Carlos

On 3/7/06, Carlos Guâno Grohmann <carlos.grohmann at gmail.com> wrote:
> 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
> +-----------------------------------------------------------+
> _________________
> "Good morning, doctors. I have taken the liberty of removing Windows
> 95 from my hard drive."
> --The winning entry in a "What were HAL's first words" contest judged
> by 2001: A SPACE ODYSSEY creator Arthur C. Clarke
>


--
+-----------------------------------------------------------+
              Carlos Henrique Grohmann - Guano
  Geologist M.Sc  - Doctorate Student at IGc-USP - Brazil
Linux User #89721  - carlos dot grohmann at gmail dot com
+-----------------------------------------------------------+
_________________
"Good morning, doctors. I have taken the liberty of removing Windows
95 from my hard drive."
--The winning entry in a "What were HAL's first words" contest judged
by 2001: A SPACE ODYSSEY creator Arthur C. Clarke