Displaying 20 results from an estimated 1000 matches similar to: "mat2listw function"
2013 Nov 27
0
trouble using mat2listw function to create spatial weights object
Hi all,
I am attempting to create a weights object and perform a Moran I test as
well. I have a very large spatial weights matrix (roughly 22,000x22,000)
that was created in Excel and read into R, and I'm now trying to implement:
library(spdep)
SW=mat2listw(matrix)
I am getting the following error:
Error in if (any(x<0)) stop ("values in x cannot be negative"): missing
value
2007 Oct 15
1
Distance matrix in SpDep-package
Hello everybody,
I would like to use the SpDep-package (especially the Local Moran index
analysis and the Getis-Ord statistics) in R for analysing my data. However,
I don't have x-y coordinates, but my data is in a distance matrix format. Is
it possible to use the SpDep package with predefined distances as well
instead of letting the program determining the distance itself by the
function
2009 Jan 07
1
troubles performing Moran.I test
dear R users,
I have troubles performing Moran.I test as suggested on
http://www.ats.ucla.edu/stat/r/faq/morans_i.htm
my spatial data are longitude and lattitide of communities. The
calculation of the inverse distance matrix according to the homepage
(using my data)
datAL <- read.csv2("C:\\Konvergenz AL.csv", header=T)
ALdist <- as.matrix(dist(cbind(datAL$L?nge,
2004 Aug 19
3
Do you know if you can map a large minimum spanning tree in R?
Thanks Mike.
My data has longitude and latitude coords and I used distAB {clim.pact}
then mst {ape} to calculate my minimum spanning tree. The nodes are
telecoms sites from all over Australia. My goal is to determine the
minimum cost of linking them via cabling, and I'm starting by
calculating the distance "as the crow flies", but will probably
eventually need to calculate the
2007 Dec 21
1
matrix to gal object
useR's
I need transform the matrix
wdat
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 0 1 0 1 1 0
[2,] 1 0 0 1 1 0
[3,] 0 0 0 0 1 1
[4,] 1 1 0 0 1 0
[5,] 1 1 1 1 0 0
[6,] 0 0 1 0 0 0
to gal object. How I do with spdep?
Thanks in advance for the help.
Bernardo.
University of Concepci?.
2005 Jan 30
1
New user...tips for spdep
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2005 Jan 30
1
New user...tips for spdep?
Hello List,
I'm a very new user to the R system. I'm only beginning to learn the
basics, but so far I've been able to do little more than try a few examples,
and of course begin reading the documentation.
My primary motivation for exploring R is the availability of tools like the
'spdep' package for calculating spatial statistics such as Geary's C and
Moran's
2007 Feb 06
2
How to do "moran's I test"?
I want to do "moran's I test" in R language. I try to use "gearymoran" in
Package "ade4","moran" in Package "spdep", and Moran.I in Package "ape". But
I do not know how to do it because data format is different.
My data:
x y dbh
111.03 10.7 7
118.11 0.28 1.2
165.36 0.36 8.4
2003 Dec 09
0
The spdep package
Hi,
Here is a listw object z corresponding to the matrix W. I understand n,
nn, S0, S1 and S2 in the weights constants summary. Is it simply so that
n1 = n-1, n2 = n-2 and n3 = n-3? If this is true where they are needed?
Just wondering
Osmo
> W
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9]
[1,] 0 1 0 1 0 0 0 0 0
[2,] 1 0 1 0 1 0
2003 Jun 06
2
Moran's index
Hi,
I am looking for some code for Moran's I. Has anyone previously done this?
I have been unable to find it in the search engines.
James
2009 Jun 06
1
large numbers of observations using ME() of spdep
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
2010 Nov 29
1
Moran I for very large data set
Hi
Are there any more efficient ways of calculating the neighbourhood object for large datasets?
I am trying to compute Moran I statistics for a very large data set (over 14,000 points). I have been using moran.test from the spdep package and everything works fine for a small data set (200 points). However, applying the same script to the whole dataset is taking days to compute (it so far has
2004 Aug 25
1
Newbie Question: Spatial Autocorrelation with R Tutorial?
Howdy All,
I am looking for some good tutorials (books, websites, whatever) for calculating/testing for Spatial Autocorrelation using R.
Specifically, I am wanting to test for autocorrelation of a number of variables measured at a set of discrete locations.
Up to this point I have been exploring the "spdep" package and I can get "moran.test" to work, but I am concerned that
2008 Apr 18
1
spdep question - Moran's I
Dear all,
I would like to calculate a Moran's I statistic using the moran function in the spdep package. The problem I'm having deals with how to create the listw object.
My data stems from the area of social network analysis. I have list of poeple and for each pair of them I have a measure of their relationship strength. So my dataset looks like: Jim; Bob; 0.5
This measure of
2011 Apr 19
1
SPDEP Package, neighbours list for Moran's I on large grid dataset
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Nom : non disponible
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2004 Jun 18
1
how to store estimates results as scalars of a matrix?
Dear R users,
I've written a loop to generate Moran's test (spdep package) on serval
subsamples of a large dataset. See below a short example.
My loop is working fine, however I would like to be able to store the test
results as lines of a matrix, that I would latter be able to export as a
dataset. My problem is that I'm not sure how I could do this using R.
Any help will be much
2007 Dec 14
0
kernel density in space
Hello everybody,
I would like to determine kernel densities along a maze. I have distances
from each point of the maze to its neighbours and I managed by means of the
mat2listw-function in the Spdep package to assign neighbours to each point.
Each point now has a value for a Z-variable and it is this variable that I
would like to use to determine a density for each point with neighbours
2008 Mar 31
1
GeoDa spdep
My question is in regard to the spdep and GeoDa packages. Do you know how
to extract a neighborhood/adjacency matrix from R? I need a matrix that has
all the neighborhoods on the X and Y axis, and then a r=1 when the
neighborhoods touch, and a r=0 when neighborhoods don't touch. I
think the Moran's I functions use a matrix like this when they estimate
Moran's I. I can estimate
2004 Apr 26
2
Spatial Autocorrelation for point data
Hi R helpers,
Is there a function (package?) in R available which tests "spatial
autocorrelation" between points (e.g. vector layer of weather stations)?
(e.g. Moran's I...)
Via the archives we found out that there is a package 'spdep' which uses
grid data for testing spatial autocorrelation.
Thanks a lot,
Jan