search for: corratio

[hoping to redeem myself for my last spurious bug report] From ?corRatio: Letting d denote the range and n denote the nugget effect, the correlation between two observations a distance r apart is (r/d)^2/(1+(r/d)^2) when no nugget effect is present and (1-n)*(r/d)^2/(1+(r/d)^2) when a nugget effect is assumed. This disagrees with the C code (corSt...

...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 but real spatial au...

...e | Subject, data = dataset) m0<-nlsList( DO ~ SSlogis(mtime, asym, xmid, scal), data = Joy) m1.nlme<-nlme(m0) m3.nlme<-update(m1.nlme,random=(asym~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...

  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