[R-sig-Geo] Questions about spautolm

[ONKELINX, Thierry]

Dear all,

I have a few questions about spautolm from the spdep package.

I get warning about "Assymetric weights" with family = "CAR". The
weights are defined like the code below. The dataset is roughly based on
a 1000 x 500m grid. But only the gridpoints in forest are measured.
Hence it is not possible to get symmetric weights. Is this violating an
assumuption of the model? Or can this cause another problem?

Buren <- dnearneigh(cbind(dataset$X, dataset$Y), d1 = 0, d2 = 6500)
Weights <- nb2listw(Buren, style = "W", zero.policy = TRUE)

My second question is about prediction. Is it possible to use a spautolm
model to make predictions for other locations?

Regards,

Thierry

------------------------------------------------------------------------
----
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
Cel biometrie, methodologie en kwaliteitszorg / Section biometrics,
methodology and quality assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium 
tel. + 32 54/436 185
Thierry.Onkelinx at inbo.be 
www.inbo.be 

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to
say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of
data.
~ John Tukey

Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer 
en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is
door een geldig ondertekend document. The views expressed in  this message 
and any annex are purely those of the writer and may not be regarded as stating 
an official position of INBO, as long as the message is not confirmed by a duly 
signed document.