Dear spdep users,
I tried to follow below command to create a neighborhood list. The
data "Matrix.txt"
is enclosed
> mat0 <- read.table("Matrix.txt", header=FALSE, sep="\t", fill=TRUE)
> mat <- as.matrix(mat0)
> dim(mat)
[1] 46 46
> summary(c(mat))
Min. 1st Qu. Median Mean 3rd Qu. Max. NA's
1 1 1 1 1 1 1918
> mat[is.na(mat)] <- 0
> summary(c(mat))
Min. 1st Qu. Median Mean 3rd Qu. Max.
0.00000 0.00000 0.00000 0.09357 0.00000 1.00000
> lw <- mat2listw(mat, style="B")
Warning message:
In nb2listw(res$neighbours, glist = res$weights, style = style, :
zero sum general weights
> summary(lw)
Characteristics of weights list object:
Neighbour list object:
Number of regions: 46
Number of nonzero links: 198
Percentage nonzero weights: 9.357278
Average number of links: 4.304348
2 regions with no links:
2 18
Link number distribution:
0 2 3 4 5 6 7 8
2 5 5 14 8 9 1 2
5 least connected regions:
7 8 9 36 41 with 2 links
2 most connected regions:
24 38 with 8 links
Weights style: B
Weights constants summary:
Error in print(data.frame(rbind(unlist(spweights.constants(object,
zero.policy = zero.policy))[c(1, :
error in evaluating the argument 'x' in selecting a method for function
'print': Error in spweights.constants(object, zero.policy = zero.policy) :
regions with no neighbours found
> is.symmetric.nb(lw$neighbours)
[1] TRUE
The neighborhood list cannot be used in spatial regression. The main
error seems to be "Error in
print(data.frame(rbind(unlist(spweights.constants(object, zero.policy =
zero.policy))[c(1, :
error in evaluating the argument 'x' in selecting a method for function
'print': Error in spweights.constants(object, zero.policy = zero.policy) :
regions with no neighbours found"
Is there anyone know what wrong with the data? I have tried to add
"zero.policy=true". Thanks
Happy Easter
1 1
1
1
1
1 1
1
1
1 1
1 1 1
1
1
1
1
1 1
1 1
1
1
1
1
1
1 1
1 1
1
1 1
1 1
1 1
1 1
1 1 1
1 1
1
1 1
1
1
1
1 1 1
1
1
1
1 1
1
1 1
1
1 1
1 1
1
1
1
1
1
1 1
1
1
1
1 1
1
1
1
1
1
1 1
1
1 1
1
1
1
1 1 1 1
1
1 1
1
1 1
1
1
1 1
1
1
1
1 1
1
1 1
1 1
1 1
1
1
1
1
1
1 1
1
1 1
1
1 1
1
1
1
1 1
1
1 1
1
1
1
1
1
1
1
1
1
1
1
1
1 1 1
1
1
1 1 1
1
1 1 1
1
1
1
1
1
1 1
1
1
1
1
1
1 1
1
1
1
1
1
1
1 1
1 1
1
1 1
1 1
1
1
1 1
1 1
_______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
