similar to: bootstrapping nlme fits (was boot function)

Hello everyone I have data grouped by subjects and i used the trellis plot to show the curve for each subject. I have another vector "a" which gives me the highest points the curves for each subjects can achieve ( the curve is exponential ). Now i want to draw a horizontal line, whose values are saved in "a", on each plot for each subject. Is there any possibility to do that?

Hello everyone I've got another question on Trellis plots. I plotted my fitted model with plot(augPred(fitted model)). According to the description of this method, one can use any optional argument which is passed down to the xyplot function for Trellis plots. Additionally to the trivial plot i would like to insert a horizontal line. I tried to do it with the argument panel= function (...)

Hello! Several of us here have tried to change the dark grey background color of the graphics device, without success. This grey background color only so far appears for Trellis plots. All other plots are shown with white background color. Is there any way to change this color? Regards Dassy

Hi all, well i know this was probably already posted many times, couldnt find anything about it though. This is a beginner problem. I have a Trellis plot which is very large, i.e. it only shows me the last few panels (after going automatically through the first ones and stopping at the last few). When i scrole with PageUp or Page down it shows me the panels of a graph i did last time but not of

Hi all, I skimmed through the archives and couldnt really find an answer to my question. One thing i dont understand of the description of the function boot() is the second variable for statistics. I have a sample of say 19 subjects out of these, using boot(), i would like to generate say 1000 samples. For these 1000 samples ill calculate an nlme() and ill use these 1000 estimators of a variable

Im trying to import data from an excel sheet or a sas file to R...im not succeeding. Apparently the function read.xport for reading a SAS file doesnt exist. What do i have to type in EXACTLY to read from an excel sheet(i guess i would be using read.table?)? Thanks in advance for an answer Dassy

Hi R-Help! I am trying to use R2WinBUGS but I get the following error message in WinBUGS (and there must be something wrong with my R statement as I tried it directly in WinBUGS and it worked): display(log) check(C:/Documents and Settings/Daikon/Roche/pop_model.txt) model is syntactically correct data(C:/Documents and Settings/Daikon/Roche/data.txt) expected key word structure compile(7) ...(and

Dear R-Users! Is there a possibility in R to do analyze longitudinal survey data (repeated measures in a survey)? I know that for longitudinal data I can use lme() to incorporate the correlation structure within individual and I know that there is the package survey for analyzing survey data. How can I combine both? I am trying to calculate design-based estimates. However, if I use svyglm() from

Hi, Let me start my saying that I am new to R hence my grasp of the appropriate used of R coding is undoubtedly way behind many on this forum. I am trying to use boostrapping to derive errors around my parameter estimate for the fixed effects in the following model. It is simply estimating the number of times an animal might cross a road based on the road's distance from a stream. I have

Hi I am sure there is a function out there already but I couldn't find it. I have SNP data, that is, a matrix which contains in each row two characters (they are different in each row) and I would like to convert this matrix to a binary one according to the minor allele frequency. For non-geneticists: I want to have a binary matrix for which in each row the 0 stands for the less frequent

Hello, I will start out with the caveat that I'm not a statistician by training, but have a fairly decent understanding of probability and likelihood. Nevertheless, I'm trying to fit a nonlinear model to a dataset which has two main factors using nlme. Within the dataset there are two Type categories and four Tissue categories, thus giving me 8 datasets in total. The dataset is in

Hi I was wondering if there was a way to run system when there is e.g. a C program which is not totally command-line driven. That is, I have a C program which requires manual input of options into the shell during the run. I would like to run this program from R and as far as I have seen system() does not handle manual options (?). Is there thus a way to use these C programs anyway through R

Dear all Please help me with correct syntax of predict.nlme. I would like to predict from nlme object for new data. I used predict(fit.nlme6, data=newdata) but I have always got fitted values, no matter how I changed newdata. I have > summary(fit.nlme6) Nonlinear mixed-effects model fit by maximum likelihood Model: konverze ~ SSfpl(tepl, A, B, xmid, scal) Data: limity.gr AIC

Hi I have sent a previous email "Error in dyn.load()" for which, shame on me, I later found a partial answer. I have been trying to look into what I exactly need to include into Makevars and where it needs to be located and have not found a satisfying answer yet. Maybe the following questions are helpful for other people as well. Again, I am trying to include a C function tools.c into

Hi I would like to produce a red shading I figured the easiest way to do that would be to use rgb in the following way: a <- seq(0,0.9,by=0.1) redshade <- rgb(red=1,green=a, blue=a) However, I don't really know how to plot things using hexadecimal colors. I used a function which tries to find the closest color to the rgb shades but it didn't work very well. Any

Dear helpers, I'm estimating multilevel regression models, using the lme-function from the nlme-package. Let's say that I estimated a model and stored it inside the object named 'model'. The summary of that model is shown below: Using summary(model)$tTable , I receive the following output: > summary(model)$tTable Value Std.Error DF t-value

Dear forum members, What is the formula to calculate denominator degrees of freedom (den df) for nonlinear mixed-effect models with covariates? My model is similar to a CO2 uptake example from Pinheiro and Bates (2000, page 376). In this CO2 dataset, there are two treatments and two types (84 observations in total), but den df for each parameter of the model is 64. Isn’t it too high? Your

Hi, I am aware that this question might be a basic one. I did browse the help and archives but I still haven't understood how to do the following: I run R locally and would like to read in data from a server for which there is a username and password. That is, how do I open a connection to a server with a password? Thanks, Hadassa -- Hadassa Brunschwig PhD Student Department of Statistics

Hi I compouted a multiple linear regression with repeated measures on one explanatory variable: BOLD peak (blood oxygenation) as dependent variable, and as independent variables I have: -age.group (binaray:young(0)/old(1)) -and task-difficulty measured by means of the reaction-time 'rt'. For 'rt' I have repeated measurements, since each subject did 12 different tasks. -> so

Hi R-Help! My question: I have lifetime/failure data of machines with different stress levels and i think an weibull/extreme value distribution would fit this data. So I did: model1 <- survreg(Surv(lfailure)~stress,data=steel,dist="extreme") (where lfailure=log(failure)) Now I would like to do a likelihood ratio test to test the hypothesis H0: location parameters of the