similar to: user-defined correlation structure in NLME

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

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

I am using the latest version of R on a Windows machine and get the following error when I try to initialize a correlation structure with the function corAR1 in NLME. This example is taken from the book of Pinheiro and Bates, so it should work. What is going wrong? > library(nlme) > data(Orthodont) > cs1AR1 <- corAR1(0.8, form= ~1 | Subject) > cs1AR1 <- initialize(cs1AR1, data =

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

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

Dear All: I am trying to fit a special case of a 2-banded Toeplitz correlation structure. A 2-banded Toeplitz has ones on the diagonal, a correlation, RHO1, on the first off-diagonal, and a correlation, RHO2, on the second off-diagonal, with zeros on all subsequent off-diagonals. After reading relevant sections in Mixed-Effects Models in S and S-PLUS (Pinheiro & Bates, 2000) and searching

Dear All: I am trying to fit a special case of a 2-banded Toeplitz correlation structure. A 2-banded Toeplitz has ones on the diagonal, a correlation, RHO1, on the first off-diagonal, and a correlation, RHO2, on the second off-diagonal, with zeros on all subsequent off-diagonals. After reading relevant sections in Mixed-Effects Models in S and S-PLUS (Pinheiro & Bates, 2000) and searching

Dear All: I am trying to fit a special case of a 2-banded Toeplitz correlation structure. A 2-banded Toeplitz has ones on the diagonal, a correlation, RHO1, on the first off-diagonal, and a correlation, RHO2, on the second off-diagonal, with zeros on all subsequent off-diagonals. After reading relevant sections in Mixed-Effects Models in S and S-PLUS (Pinheiro & Bates, 2000) and searching

Dear all, I am trying to define my own corStruct which is different from the classical one available in nlme. The structure of this correlation is given below. I am wondering to know how to continue with this structure by using specific functions (corMatrix, getCovariate, Initialize,...) in order to get a structure like corAR1, corSymm which will be working for my data. Thanks in advance.

Dear Friends, I am seeking for any help on an error message in lme functions. I use mixed model to analyze a data with compound symmetric correlation structure. But I get an error message: "Error in corMatrix.corCompSymm(object) : NA/NaN/Inf in foreign function call (arg 1)". If I change the correlation structure to corAR1, then no error. I have no clue how to solve this problem.

I am using lmList, which takes 'Data' partitioned according to the levels of a grouping factor (gf) and individual 'lm' fits are obtained for each 'data'partition, using a model defined as in "lm". So my call to lmList looks something like: > mg.lis <- lmList(strmbf ~ age1c + gender1 + sysbp.clinic + + diabp.clinic + ldl1 + mets.total + bmi1c |

After installation of the latest version of R (2.6.0) I have a problem with loading the nlme library. When I use RGui under Windows XP, and try to install the nlme package, I get a warning that installation was unsuccessful due to a previously installed version of nlme. But the nlme library does not appear on the list of libraries that are available for loading under RGui. This happens after a

I have been looking at a draft of Doug Bate's book on mixed effects models (http://lme4.r-forge.r-project.org/book), and in chapter one (section "1.4.2 Matrices and Vectors in the Fitted Model Object", to be exact) he refers to the function env() for checking the environment of a fitted lmer object. This function does not appear under help, and I have not been able to find

Dear R Friends, I need help with an error associated with corCompSymm in an lme fit. I am using a mixed effects model to analyze a split-plot with repeated measures and would like to fit with the compound symmetry correlation structure. This problem doesn't occur when using corAR1 or any of the other structures. I would greatly appreciate help on how to solve this issue. Here's my

Hi all, I have a very high dimensional data and apparently there are several columns that contain similar information (some columns are equal). I want to form a matrix/data frame consisting of unique columns. Does anyone have an efficient way of getting out these columns. A small section of the data frame is given below. Thanks for helping. Stephen. > newdata [,1] [,2] [,3] [,4] [,5]

Full_Name: Hao Yu Version: 1.4.1 OS: Windws and Linux Submission from: (NULL) (129.100.45.161) Hi, Recently we did some benchmarks regarding matrix inverse operation and found some strange things. See the following results (the package Matrix is most updated). 1. load the function Toeplitz and library(Matrix) "Toeplitz" function(x) { matrix(x[1 + abs(outer(seq(along = x),

Hi all, I am trying to set up a simple path analysis in the SEM package, but I am having some trouble. I keep getting the following error message or something similar with my model, and I'm not sure what I'm doing wrong: Error in solve.default(C) : system is computationally singular: reciprocal condition number = 2.2449e-20 In addition: Warning message: In sem.default(ram = ram, S = S,

hHllo, I'm looking for an algroithm to transform an existing toeplitz matrix (autocorrelation matrix) to the nearest positive semidefinite toeplitz matrix. I merely found an algorithm to transform an correlation matrix via the function nearcor() based on the algorithm of Higham. But as I examined, it destroys the toeplitz structure of my underlying matrix. Does any function already exist

Hello I would like to generate covariance matrix with autoregressive structure. I saw some functions in nlme such as corAR1 for example but I don't know how to use it for my goal. Could someone help me or advise me another function? Thank you in advance Caroline

[Hope this is the right list where to send...] An attempt to update package 'mnormt' involves the addition of a small new function called 'pd.solve'. When I come to the package checking stage, an error occurs in parsing pd.solve.Rd. The full transcript of the outcome is copied below (it includes details on my installation) but the critical point is where the \examples{} section