[R] large numbers of observations using ME() of spdep

lucero mariani lucero.mariani at gmail.com
Sat Jun 6 19:50:37 CEST 2009


Dear All,
We aim to remove the spatial structure of our data using Moran Eigen
Vectors and spdep package . Our data has 3694 samples and 13
variables.
The computer stop working after almost 4 days of processing (we found
it emitting a sharp sound and with all colors on the screen. No
wories, it was restared without problem!). And we are left with
nothing: no result file was produced since the calculations were
interrumpted!
Consequently, I am looking for a way to accelerate calculations with
ME() of spdep and to save the results step by step (for each eigen
value).
I came accross several promissing ideas: 1)make a compiled program in
C and call it in R with the command system(); 2)use muliR. However, I
do not know how to use these tools. I do not understand exactely why
the calculations are so slow and I do know know how to write a program
in C...
I am using Ubuntu 9.04 and R version 2.8.1 .

The code in R is a fallows:
taimin.xy = taimin[c("dy", "dx")];
coordinates(taimin.xy) <- ~dy+dx; #dy, dx, name of the respective
coordinate columns
coords<-coordinates(taimin.xy);
library(spdep);
TaiminGabrielGraph<-gabrielneigh(coords, nnmult = 12);
tai.gab.nb<-graph2nb(TaiminGabrielGraph,sym=TRUE);
nbtaim_distsg <- nbdists(tai.gab.nb, coords);
nbtaim_simsg <- lapply(nbtaim_distsg, function(x) (1-((x/(4*50))^2)) );
MEtaig.listw <- nb2listw(tai.gab.nb, glist=nbtaim_simsg, style="B");
sevmtaig <- ME(Presabs
~Age+Curv+Zon2005+ZoneMeiji+Wi+Sol+Slope+Seadist+Elev+Basin,data=taimin,
family=binomial,listw=MEtaig.listw)

Any help is welcome!

Thanks

Lucero Mariani, Yokohama National University, Japan.




More information about the R-help mailing list