Dear List,

I am performing a spatial analysis for gridded data with ~8000 cells. Each
grid cell is 10 x 10 km and has one dependent and 5 independent variables.
The dependent variable is log-transformed and has some NAs, as do the
independent variables.

I set up the lm() function using na.action=na.exclude (different from the
default na.omit, since the lm documentation says that na.exclude pads the
residuals to the correct length and fills with NA). Using a 1st order queen
weights matrix generated keeping zero.policy=TRUE, I ran the lm.morantest()
function, which returned this error:

> allxform.lm.moran.queen <-
lm.morantest(ols.allxform,vulcgrid.queen.nb.w,alternative = "two.sided")
Error in nb2listw(neighbours = subnb, glist = NULL, style = style,
zero.policy = zero.policy) :
  Empty neighbour sets found

repeating the same using an 8 nearest neighbour matrix also yielded the same
error:

> allxform.lm.moran.queen <-
lm.morantest(ols.allxform,vulcgrid.knn8.w,alternative = "two.sided")
Error in nb2listw(neighbours = subnb, glist = NULL, style = style,
zero.policy = zero.policy) :
  Empty neighbour sets found

I then tried reading in a 45km distance thresholded neighbour matrix
generated in OpenGeoDa using read.gwt2nb(), after converting to listw using
zero.policy=TRUE and style="W". Running lm.morantest using this weights
matrix returns the error:

> allxform.lm.moran.queen <-
lm.morantest(ols.allxform,vulcgrid.nb.dist.45km.gwt.w,alternative =
"two.sided")
Error in lm.morantest(ols.allxform, vulcgrid.nb.dist.45km.gwt.w, alternative
= "two.sided") :
  objects of different length

Checking length of the objects, which I presume are "ols.allxform" (my lm
result) and "vulcgrid.nb.dist.45km.gwt.w":

> length(ols.allxform)
[1] 13
> length(vulcgrid.nb.dist.45km.gwt.w)
[1] 3


Weights matrix summary:

> vulcgrid.nb.dist.45km.gwt.w
Characteristics of weights list object:
Neighbour list object:
Number of regions: 8281
Number of nonzero links: 533700
Percentage nonzero weights: 0.7782724
Average number of links: 64.44874

Weights style: W
Weights constants summary:
     n       nn   S0       S1       S2
W 8281 68574961 8281 261.9284 33173.84

I then ran the lm.LMtests() function on the same linear model for the
queen's weights matrix and for the distance thresholded weights matrix
yileding the same error..

> chi.lmtest.nohdr <- lm.LMtests(ols.allxform, vulcgrid.queen.nb.w,
zero.policy=NULL, test="all", spChk=NULL, naSubset=TRUE)
Error in lm.LMtests(ols.allxform, vulcgrid.queen.nb.w, zero.policy = TRUE,
 :
  objects of different length

sessionInfo output:

R version 2.11.1 (2010-05-31)
x86_64-pc-mingw32

locale:
[1] LC_COLLATE=English_United Kingdom.1252  LC_CTYPE=English_United
Kingdom.1252
[3] LC_MONETARY=English_United Kingdom.1252 LC_NUMERIC=C

[5] LC_TIME=English_United Kingdom.1252

attached base packages:
[1] grDevices datasets  splines   graphics  stats     tcltk     utils
methods   base

other attached packages:
 [1] pgirmess_1.4.9      RandomFields_1.3.41 plyr_1.2.1
 robust_0.3-11
 [5] rrcov_1.1-00        pcaPP_1.8-3         mvtnorm_0.9-92
 robustbase_0.5-0-1
 [9] sandwich_2.2-6      zoo_1.6-4           rgdal_0.6-28
 raster_1.8-9
[13] RNetCDF_1.2-1.1     clim.pact_2.2-41    akima_0.5-4         ncdf_1.6.3

[17] car_2.0-2           nnet_7.3-1          tkrplot_0.0-19
 TeachingDemos_2.7
[21] sphet_1.1-0         fields_6.3          spam_0.23-0         geoR_1.6-32

[25] RColorBrewer_1.0-2  spdep_0.5-33        coda_0.13-5
deldir_0.0-12
[29] maptools_0.7-38     foreign_0.8-40      nlme_3.1-96         MASS_7.3-7

[33] Matrix_0.999375-39  lattice_0.18-8      boot_1.2-42         sp_0.9-71

[37] survival_2.35-8

loaded via a namespace (and not attached):
[1] grid_2.11.1   stats4_2.11.1 tools_2.11.1


Suggestions are greatly appreciated!

Regards,

-- 
advait godbole

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