similar to: Adding Spatial Correlation Strucutre to Logistic Regression / Contingency Analysis

Displaying 20 results from an estimated 4000 matches similar to: "Adding Spatial Correlation Strucutre to Logistic Regression / Contingency Analysis"

2006 Jan 12
4
How do you create a tree strucutre with ActiveRecord
I want to build an application that has the concept of administrative domains. What I mean by this is that administrators have access to different data, based on what domains they are a member of. The domain strucutre is hierarchical. Here is an example: - MLB - AL - East - Yankees - Red Sox ... + Central + West - NL + East + Central + West Now
2012 Jul 31
2
Spatial regression
Dear list members, I have a large dataset with point data. Each data point has X, Y, number of species present and values for one single explanatory variable. Each point was generated from a polygon grid shapefile and they are at equal distances. I conducted GLS analyses introducing variance structures and correlation structures to improve the model. I plotted variograms before and after adding
2008 Apr 01
1
spatial cross-correlation
Hi; I cannot find in the R html documentation a way to evaluate cross-correlation in 2D data sets. I would like to evaluate cross-correlation in a series of moving windows between two maps. i,e, specify several windows inside the complete 2D spatial matrixes and for each one ofthese windows evaluate the 2D cross-correlation (commonly conducted in the spectral domain). Thanks in advance and best
2009 Mar 03
1
spatial markov chain methods
Hello, can any one point me to R-packages (if available) which include spatial Markov Chain methods? My second question is more general but hopefully not OT: Currently we are using the software TPROGS, which let people simulate property distributions in space by some Markov Chain approaches. We face some problems due to the lack of information between distances of samples along borehole path
2005 Mar 31
1
Contingency table: logistic regression
Hi, I am analyzing a data set with greater than 1000 independent cases (collected in an unrestricted manner), where each case has 3 variables associated with it: one, a factor variable with 0/1 levels (called XX), another factor variable with 8 levels (X) and a third response variable with two levels (Y: 0/1). I am trying to see if X1 has an effect on the relationship between X2 and the
2009 Dec 17
0
nonlinear (especially logistic) regression accounting for spatially correlated errors
Hello, Sorry to be a bit longwinded, but I've struggled quite a bit with the following over the last few days. I've read all entries related to spatial autocorrelation in R help and haven't found what I'm after. If it's okay, I'm going to first describe my general understanding of the process by which a mixed model can account for correlated errors. If possible, please
2005 May 17
0
problem with gls : combining weights and correlation structure
Dear R-users, I hope you will have time to read me and I will try to be brief. I am also sorry for my poor english. I used gls function from the package nlme to correct two types of bias in my database. At first, because my replicates are spatially aggregated, I would like to fit a corStruct function like corLin, corSpher, corRatio, corExp or corGaus in my gls model, and simultaneously,
2003 Jul 31
1
spatial statistics vs. spatial econometrics
Dear R users, I am putting together reading and resources lists for spatial statistics and spatial econometrics and am looking for some pointers from more experienced practitioners. In particular, I find two "camps" in spatial modelling, and am wondering which approach is better suitied to which situation. The first camp is along the lines of Venables and Ripley's Chapter 14
2003 Jun 30
2
spatial correlation test
hello, I want to do a test for spatial correlation. I tried it with geary.test() but I don't understand the required input. x= a numeric vector the same length as the neighbours list in listw (my sampled data, I assume) listw= a listw object created for example by nb2listw (well when I check nb2listw() I get to "neighbours - an object of class nb" - but I couldn't figure
2012 Aug 17
0
spatial auto-correlation structure in nlme
Dear R users, I'm estimating a mixed effects model in which the spatial correlation is controlled for by the "corGaus" structure. I'm wondering if there is a document or paper that explains how the spatial correlation structure (such as "corExp" or "corGaus") works. Let me use the example and data posted on UCLA's R FAQ webpage to explain my problems.
2005 Jun 07
0
user-defined spatial correlation structure in geeglm/geese
Dear all, We have got data (response and predictor variables) for each country of the world; I started by fitting standard GLM and tested for spatial correlation using variogram models (geoR) fitted to the residuals of the GLM. Spatial autocorrelation is significant. Therefore, I think about using general estimation equations (geeglm or geese in geepack) allowing for residual spatial
2012 Oct 10
1
glmmPQL and spatial correlation
Hi all, I'm running into some computer issues when trying to run a binomial model for spatially correlated data using glmmPQL and was wondering if anyone could help me out. My whole dataset consists of about 300,000 points for which I have a suite of environmental variables (I'm trying to come up with a habitat model for a species of seal, using real (presence) and simulated dives
2011 Mar 25
1
spatial stats - geoR - variogram - standard deviation
Hello, I am attempting to get the standard deviation in multiple distance bins in my spatial data. It appears as though the 'variog' command in the geoR package will do the trick, as one of the outputs from 'variog' is 'variog$sd', which, according to the manual, is the "standard deviation of the values in each bin". However, when I run this command, the
2011 Nov 16
0
calculating variograms (gstat) with large data sets
Dear all, I am aiming to calculate variograms using variogram() from gstat. The problem is that some of my data-sets are very large (> 400000 points). Running the command takes some hours of time and does not give any error-message. Nevertheless the result seem not to be appropriate - the first few bins are ok (up to a distance of about 300) but then it gains lags which are much larger than
2006 Sep 28
0
mx2 contingency tables or (2^(m-1)-1)'s 2x2 contingency tables in the context of feature selection for random forest
Dear Listers: I have a categorical feature selection problem for random forest. Suppose I have a multiple-leveled category variable A, which has m=3 levels: red, green, and blue and the final target is binary classification. I want to evaluate its power in discrimination between 2 classes. We know rf splits multiple-leveled category variable by considering all combinations of its levels. So
2006 May 17
4
weird prototype error when using RJS
I''m trying to set up a nested menu strucutre using RJS I want to be click on an item, have not have the whole page refresh but just have the menu <li id=''Selection''> refreshed 1 - my model is using :acts_as_tree 2 - in my controller I have the following.. it''s just a barebones start at being able to dig DOWN through the chilren def renderMenu
2004 Sep 16
1
geoR/variog4() not returning all directions
Mac OS 10.3.5, R 2.0.0 latest version of geoR I have an incomplete 5 x 20 spatial array of samples (60 out of 100 possible locations) for which I would like to calculate directional variograms using variog4(). Unfortunately, I can't get it to return all 4 directions. It returns variograms for 45, 90, and 135 degrees, omitting 0 degrees (pi/4, pi/2, 3pi/4, omitting 0). If I specify 0
2010 Jun 25
1
variograms and kriging
Hello Trying to develop variograms and kriged surfaces from a point file. Here is what I've done so far. library(gstat) # also loads library(sp) library(lattice) soilpts$x <- soilpts$UTM_X soilpts$y <- soilpts$UTM_Y soil.dat <- subset(soilpts, select=c(x, y, Area, BulkDensity, LOI, TP, TN, TC, Total_Mg)) dim(soil.dat) [1] 1292 7 coordinates(soil.dat) <- ~ x+y
2009 Jun 11
0
Variogram fitted by Cauchy
Hi I'm using R(2.9.0) and gstat package under Windows to plot sample variograms. When I want to fit them, I don't have the possibility to choose Cauchy functions. Under Mathematica for example, we have it and it seems to be the best one to fit the variograms I have I tested the others functions, they can fit but I would,if possible, use the Cauchy one. If anybody knows something about
2009 Feb 24
2
Simulating contingency table (Basic question, help please)
I'd like to carry out a Monte Carlo simulation test where given data is a contingency table. I think this is something to do with using rmultinonom(), but I'm not sure how to code this, to simulate contingency tables. Could anyone please help with how to use R to simulate contingency tables like this? -- View this message in context: