similar to: correlation structures in NLME

Dear R-help, I am trying to set up linear mixed effects models in R using the (recommended) nlme package (R version 2.3.1 on a Linux platform). When trying to reproduce an example from Jose Pinheiro & Douglas Bates (2000, p 210) I get the following error message (code to produce message pasted as well): library("nlme") data("Orthodont") vf1Ident <- varIdent(

Is there an "easy" way to plot a "color key" next to a color image (with image() in graphics package)? The color key should also include a numerical scale, so that the colors can be cross-referenced with image intensity values. I see that levelplot has a facility for color keys, but with image it seems less straightforward, i.e. generating a color key is not an option in

Let me modify my question about user-defined covariance structures for LME models: Can somebody tell me how I can see the code for the definition of the correlation structures that come with the NLME package. Specifically I like to see the code for the functions coef, corMatrix, and intialize for any of the pre-defined correlation structures, and use this as a template to define a new correlation

When using read.spss (library: 'foreign') I get the following warning message: Warning message: E:/R4win/mesamri.sav: Unrecognized record type 7, subtype 13 encountered in system file. I don't see anything wrong with record #7 in the database I am trying to read in, but I suspect that the warning message does not refer to a specific record, but a "variable" type. Is this

  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

I have data for several rings of a left heart chamber, and which I would like to display in concentric rings, with color-encoding of the values. Each ring corresponds to one slice through the heart, and the rings correspond to positions from the base to the apex of the heart as you move from the outermost ring to the innermost one. The data have a circular pattern. These types of displays are

While installing my small package, I met a tricky problem. For clarity, let me explain it with the following simplified example. In ~/pkg/R/aclass.R, setClass("aclass", contains="bclass", representation(i="numeric")) In ~/pkg/R/bclass.R, setClass("bclass", representation(j="numeric")) After building a "pkg" package, the file

Dear R-Users, Is it possible to get the covariance matrix from an lme model that did not converge ? I am doing a simulation which entails fitting linear mixed models, using a "for loop". Within each loop, i generate a new data set and analyze it using a mixed model. The loop stops When the "lme function" does not converge for a simulated dataset. I want to

Hello, I am using R 1.7.1 on a Redhat Linux machine, version 7.3. The following works fine: setClass("ok", representation( "A" = "matrix", "Cmatrix" = "matrix")) new("ok", "A" = diag(4), "Cmatrix" = diag(4)) But the following doesn't work: setClass("notok", representation(

"C" appears to be an illegal name for a slot in an S4 class (example below). If this is a known limitation, and not a bug, it would be nice if it were caught by setClass. Paul Gilbert > setClass("testobj", representation ( C = "numeric")) [1] "testobj" > new("testobj", C= 2) Error in methodsPackageMetaName("C", name) :

I'm in the very initial stage of expanding the formula processing in my quantile regression function rq() to handle additive nonparametric components, say qss(x), or qss(x,z). I need some advice about strategy for formula processing. My initial foray was to use: terms(formula,specials="qss") and then modify the components of the resulting terms.object. But in changing formula

Hi, I would like to fit a model for a factorial design that allows for unequal variances in all groups. If I am not mistaken, this can be done in lm by specifying weights. A function intended to specify weights for unequal variance structures is provided in the nlme library with the varIdent function. Is it apropriate to use these weights with lm? If not, is there another possibility to do

Dear R user, I have a question on using R to analyze data with repeated measurements. I have 2 species with several strains (12) per species, each of which has been measured twice with for a given trait. No particular covariance, just two measures. Now I want to analyze the data with an ANOVA (aov) considering these repeated measures to get the MSq and SSq for the species and strain level. I

Hello Experts, how do I reformat a data frame in the way described below: df1: ID desc resist thick temp 1 4711 100 5 20 2 4712 101 4 21 3 4711 99 3 19 4 4712 98 7 22 TO df2: id desc Param Value 1 4711 resist 100 1 4711 Thick 5 1 4711 temp 20 2 4712 resist 101 2 4712 Thick 4 2 4712 temp 21 3

Could somebody help with the definition of new correlation structure for use with a linear mixed-effects model (package nlme). Specifically, I want to define a Toeplitz type correlation structure, but due to my inexperience with programming in R, I feel a bit overwhelmed with the task at hand. I understand that you can start with a function like corAR1 as template, but I have no idea how I would

hello, I'm trying compile R-2.8.1. I've got Rtools installed, paths setup, etc... the compile progress up to a point and then complains: ... DLL made installing DLL collecting R files preparing package methods for lazy loading dumping R code in package `methods' initializing class and method definitions ...done make[4]: *** No rule to make target `inst/BasicClasses.R',

As far as I can tell, there's no trivial way to set arbitrary S4 slots to NULL. Most of the online examples I can find, use setClassUnion and are about 10 years old. Which, in my opinion, is defective. There's nothing "robust" about making something that should be trivially simple, really complicated. Maybe there is a simpler way, and I just haven't worked it out, yet. But

Hi Martin, Thankyou for your response. I suspect that we're not going to agree on the main point. Making it trivially simple (as say Java) to set slots to NULL. So, I'll move on to the other points here. ***Note that cited text uses excerpts only.*** > setClassUnion("character_OR_NULL", c("character", "NULL")) > A = setClass("A", slots =

Hi, The man page for new() suggests that if 'a' is an object with slots "slot1" and "slot2" and C is a class that extends the class of 'a', then the 2 following calls should be equivalent: new("C", a, ...) new("C", slot1=a at slot1, slot2=a at slot2, ...) This is generally the case but I just ran into a situation where it's not.

Thanks Martin for looking into this. H. On 05/13/2015 03:57 AM, Martin Maechler wrote: >>>>>> Herv? Pag?s <hpages at fredhutch.org> >>>>>> on Tue, 12 May 2015 15:18:42 -0700 writes: > >> Hi, > >> The man page for new() suggests that if 'a' is an object with slots >> "slot1" and "slot2" and C is a