search for: corlin

...f +s(depth, by=lakef), data=fish3) #GAMM example: bloat.gamm1 <- gamm(log10(yaobloaterbiom+0.00325) ~ lakef + s(depth, by=lakef), correlation=corAR1(form = ~ interval|tranf), data=fish3) However, GAMM results from models including a wide variety of correlation structures (corExp, CorSpher, CorLin, AR1, ARMA) produce autocorrelated residuals (similar lag range as GAM), patterns in residuals plots, and confidence intervals for predictions that are only slightly large than for GAMs. This suggests to me that GAMM is not performing much better than GAM (or I've not specified models corr...

..., 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, because my response variable is an estimate, I would like to use weights to take into account the accuracy of the estimation. I used a varFixed object corresponding to squared standard error. Variograms all shows a weak...

Hi all, I have been attempting this repeated measure analysis where correlation among observations (within each subject) is spatial. My command is: >fdat.lme1<-lme(Lint~Rep+Treatment,data=fdat,random=~1|fldPos,correlation=corLin(form=~lat+lon)) It is generating follwoing error: Error in getCovariate.corSpatial(object, data = data) : Cannot have zero distances in "corSpatial" first I thought that decimal values of latitude/longitude are resulting in extremely small values of distances, causing R to ignore it....

I noticed that ?corClasses in package nlme does not list corSpatial among the standard classes. This might either be intentional because corSpatial is not "standard" , or it might be simply an oversight that needs correcting. ------------------------------------------ Robert W. Baer, Ph.D. Professor of Physiology Kirksville College of Osteopathic Medicine A. T. Still University of

...o a simple (?) analysis of a 1D spatial data set, allowing for spatial autocorrelation. (Actually, I'm comparing expected vs. observed for a spatial model of a 1D spatial data set.) I'm using models like gls(obs~exp,correlation=corExp(form=~pos),data=data) or gls(obs~exp,correlation=corLin(form=~pos),data=data) This form is supposed to fit a linear model of obs=a*exp+b using an autocorrelation model based on the position variable "pos". The problem: I get reasonable answers for the slope & intercept, but the estimated ranges for the autocorrelation functions ar...

...~1), weights = varPower() ) m4.nlme <- update( m3.nlme, corr = corExp(form = ~ mtime) ) # R crashes m5.nlme <- update( m3.nlme, corr = corRatio(form = ~ mtime) ) # R crashes m6.nlme <- update( m3.nlme, corr = corSpher(form = ~ mtime) ) # R crashes m7.nlme <- update( m3.nlme, corr = corLin(form = ~ mtime) ) # R crashes m8.nlme <- update( m3.nlme, corr = corGaus(form = ~ mtime) ) # R crashes *sessionInfo():* R version 2.13.0 (2011-04-13) Platform: i386-pc-mingw32/i386 (32-bit) locale: [1] LC_COLLATE=French_France.1252 LC_CTYPE=French_France.1252 LC_MONETARY=French_France.125...

...*** address 0x82e4902a, cause 'memory not mapped' Violaci?n de segmento R Version 2.3.1 (2006-06-01) nlme Version: 3.1-74 Linux 2.6.12-10-386 (Ubuntu 5.10) I worked out the example of rats body weights, also in the book, and it gave no error, so the problem seems to be in using the corLin and corGaus functions with a nlme fit. Apparently is neither my version of R and nlme, nor the dataset. Can someone try to reproduce this? Or does someone knows the cause/explanation/fix? Thanks very much JR Ferrer-Paris -- Dipl.-Biol. JR Ferrer Paris ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Laboratorio d...

  Hola,   Por favor, ¿podríais indicarme qué recursos (librerías o ideas) pueden resultar de utilidad para crear un gráfico del estilo del de la figura 3.8 del siguiente link?   http://www.tsc.uvigo.es/BIO/Bioing/ChrLDoc3.html#3.5   Actualmente estoy utilizando funciones muy básicas y la verdad es que no me encuentro muy satisfecha con el resultado.   Muchas gracias.   Eva [[alternative HTML