search for: moran

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 coul...

Dear , This is Elaine. I am computing moran's I using moran.test for a generalized linear model (multiregression). The following contents are the results, and I cannot find the observed Moran's I mentioned as estimate in the manual. Please kindly help indicate if there is observed Moran's I did not notice or other method for cal...

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...

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) ALd...

...ader = TRUE, sep = ",") > Locate.dists<-as.matrix(dist(cbind(Locate$long, Locate$lat))) > Locate.dists.inv<-1/((Locate.dists)^2) > diag(Locate.dists.inv)<-0 > attri<-read.csv("countryattri.csv", header = TRUE, sep = ",") > Moran.I(attri$GDP, Locate.dists.inv, na.rm = TRUE) This gives you Moran's I (correlation coefficient) for the GDP column in the "attri" dataframe. I am trying to run the Moran.I function as a loop for all columns in the "attri" dataframe so that I can obtain Moran coefficients fo...

Hi, I am trying to calculate Moran's I test for the residuals for a regression equation, but I have trouble converting my coordinates into nb format. I have used the dnearneigh() funtion now with an arbitrarily high upper distance to make it include all plots. However, when I do the lm.morantest() I get a Moran's I value w...

Hello- I am using the vegan package PCMN() because I need to use option of row weights (I am using CCA following the selection of the significant/positive PCNM variables). In the library PCNM (PCNM function), the Moran's I is calculated for you as part of the function. I see that I need to calculate Moran's I separately in order to retain the eigenfunctions with positive spatial correlation but could use help in doing so...I have looked up Moran's I in a couple different packages but am not sure what...

Hello, I am interested in using Morans I for different time intervals to detect disease clusters. Ultimately I would like to use CUSUM - or similar monitoring statistic to monitor the results of Morans I - similar to the work by Rogerson (2005) Spatial Surveillance and Cummulative Sum Methods in Spatial and Syndromic Surveillance fo...

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

i would like to perform moran's analysis with r... thanks duccio

Dear R-users, I was wondering if someone could give me some advices on the following problem. I tried to apply moran’s test to a small dataset and couldn’t succeed, here is the error message:   mor <- moran.test(x, res2)   Avis dans moran.test(x, res2) :   Out-of-range p-value: reconsider test arguments   mor     Moran's I test under randomization data:  x  weights: res2   Moran I statistic s...

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 been going for 5 days and s...

Hi- I would like to assign distance classes (lags) to the moran''s I test in R. I don¹t have equally spaced points since I was mapping shrubs across a landscape (vs. an experiment or survey in a grid). I somehow need to select points based on the distances in the distance matrix (i.e., I need to select all pairs of points that occur 0-25 m from each...

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 data...

Are there any other wireless IP phones out there other then the Cisco 7920?? -- James Moran <jmoran@potentialtech.com> Potential Technologies

Hello all, I'm a new user of R and I have used the spdep package to calculate Moran's I estimates. I used the dnearneigh() function and moran.test() function and obtained what I wanted, but now I want to plot my results with the p-values. I regrouped my results for the Moran's I like >m=c(m1$e,m2$e...) #m1 contain the results of the moran.test for lag1 >p=c(m...

Hi, I am trying to do a Moran's I test on an ordinal logistic regression model. I have a simple spatial weights matrix listed below I would like to use. Y= 1 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 1 1 0 1 1 0 0 0 0 1 1 0 0 0 1 1 1 1 0 0 0 0 0 1 1 1 1 0 0 0 0 0 1 1 1 1 0 0 0 0 0 1 1 1 1 0 0 0 1 1 0 0 0 0 1 1 0 0 1 0 0...

Dear all, I have a question regarding the spdep package: Assume that each person within my dataset is characterized by a continuous variable y. In order to test for spatial autocorrelation in y I calculated a Moran's I statistic. The problem is that y is also likely to be influenced by a series of other variables x that are unique to each person in my dataset. To test to which extent the autocorrelation effect is present even when accounting for the effect of x, I first did a regression y = f(x) + Epsilon...

Sorry for the repetition, unless I've got bad deja vu this questions been asked before but I couldn't turn up an answer on CRAN. Is there already any code in existence for local dependence measures such as Moran's I or Getis and Ord G? Also, S-Plus has a number of interstingly named Cluster Algorithms based on some previous stand-alone fortran algorithms (agnes, daisy etc.) which have some interesting features (such as fuzzy clustering, and some potentially useful validation techniques). Are there a...

...rn 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 I, which I would like to use in an analysis for my thesis. However, I am not really sure how to get started. As a simple example, if I have a table with columns containing an ID field, X & Y coordinates, and an observation value, what steps should I follow to pre-process this data...