[R-sig-Geo] ANOVA with correlated errors

[Jose A. Hernandez]

Dear R colleagues,

My name is Jose Hernandez and work in the analysis of on-farm experiments.

I've been a R user for sometime now, however am still struggling figuring 
out some of my spatial analysis using R.

Most of my experiments have the following model:

Y_ij = Mu + r_i + T_j + e_ij

Where:
r_i is some replication and T_j some fixed treatment effect.

I many cases there is significant within block heterogeneity and therefore 
I can't assume that e_ij are iid.

An alternative is to use:

Y_ij = Mu + T_j + e_ij

And assume that:

e_ij follows some spatial covariance model such as exponential, spherical, etc.


Are there any R packages that will integrate spatial variability into the 
model ?

Thanks and advance and best regards !

Jose


-- 
Jose A. Hernandez
Ph.D. Candidate
Precision Agriculture Center

Department of Soil, Water, and Climate
University of Minnesota
1991 Upper Buford Circle
St. Paul, MN 55108

Ph. (612) 625-0445, Fax. (612) 625-2208