similar to: boot problem

Hi, I have come across the following problem which seems to be a scoping issue but I'm at a loss to see why this is so or to find a good workaround. Suppose I have a function to get a prediction after model selection using the step function. step.pred <- function(dat, x0) { fit.model <- step(lm(y~., data=dat), trace=F) predict(fit.model, x0, se.fit=T) } This function works

Hi, Suppose that I have a list where each component is a list of two matrices. I also have a vector of weights. How can I collapse my list of lists into a single list of two matrices where each matrix in the result is the weighted sum of the corresponding matrices. I could use a loop but this is a nested calculation so I was hoping there is a more efficient way to do this. To help clarify,

Hi, If columns of a data.frame have a names attribute and we rbind two similar data.frames together, the names of the column of the resulting data.frame only has the correct values for the first component and has "" in all other positions. Is this a documented "feature" or a bug? If it is intentional, why? Here is a small example to show what I mean. The same behaviour

Dear All, Anyone has some idea how to implement 632 estimator and leave-one out bootstraping method by using boot package. I know the bootstrap package has this function, but it sounds not very flexible for my project. Thanks, Jim

Hello, I am trying to carry out a bootstrap analysis (using the boot package) on a table and cannot work out how to get the results I need! I have a table ("d2") with 4 columns: "ID_code", "Age", "Quarter" and "StomWt". Age (0-5) and Quarter (1-4) are my strata Therefore I wish to estimate the confidence intervals for the mean StomWt for each Age

Hi, I using the boot package 1.2-20 on R 2.0.1. My statistics function estimates 6 parameters. In a small percentage of resampled data sets my statistics function doesn't produce an estimate for one parameter and the boot function stops with an error. I can write an ifelse(exists('parameter.estimate'), parameter.estimate, NA) statement within the statistic function to substitute

I think I am doing something wrong when I try to bootstrap R square obtained from lm. My code is included below. No matter how many times I run the simulation, I always get exactly the same result, the bias and std.error are always zero. I would think that these values should be non-zero. I would appreciate any suggestions as to what I am doing wrong, or perhaps what I fail to understand. R 2.1.0

Hello, I downloaded R today because I was told it has very good bootstrapping abilities. What I need to do is to program it (or use an existing program) to bootstrapping test for multimodality using nonparametric kernel density estimates as proposed by Efron and Tibshirani (1993). If anyone can get me started, I will be immensely grateful. Thanks. Sangeeta

Question: How can I get access to the bias value of a boot statistic? Details: Boot function: boot(data, statistic, R, sim="ordinary", stype="i", strata=rep(1,n), L=NULL, m=0, weights=NULL, ran.gen=function(d, p) d, mle=NULL, ...) When I create an object, containing the bootstrap statistic (object <- boot (....))I can call it and will get an output

What in the world am I missing?? > x<-rnorm(20) > mean(x) [1] -0.2272851 > results<-boot(x,mean,R=5) > results[2] $t [,1] [1,] -0.2294562 [2,] -0.2294562 [3,] -0.2294562 [4,] -0.2294562 [5,] -0.2294562 Jeff Morris Ortho-Clinical Diagnostics A Johnson & Johnson Co. Rochester, NY Tel: (585) 453-5794 [[alternative HTML version deleted]]

I am trying to bootstrap the parameters for a model that is estimated through the optim() function and find that when I make the call to boot, it runs but returns the exact same estimate for all of the bootstrap estimates. I managed to replicate the same problem using a glm() model but was able to fix it when I made a call to the variables as data frame by their exact names. But no matter how I

Hi, I'm using R 1.7.1 on a Windows 2K computer. For some reason erase.screen does not seem to be working correctly. That is it does not erase the requested screen. That is the old graphic is still visible and any subsequent graphics are superimposed over it making them impossible to read. What is worse is that they print out this way also. The same behaviour happens with a Windows XP

Hi, Using R1.9.1 for Windows with Windows 2000 (also XP), I have come across the following problem that I have not seen before and am at a loss to explain. If I create an object using rlm from library(MASS) and then save the workspace, I cannot reopen it using RGUI by double clicking on the .RData file as I normally do. If I double click on the icon, R starts and then gives the following

Hi Speex Developers, I'm Andrey Zhukov, the developer of PI-CONSULT GMBH company. Building a voip application that uses your libraries, i have found the strange problem with the latest version of Speex Libs. Our application works under win32, and i used before version speex 1.1.12 ( were built from sources). It seems i have resolved the known problem with clock drift of audio cards using

Hi, I just came across an error that I haven't seen before and hope someone can help me. When I try to save my current workspace (using save.image or on quitting) I get the error message Error in save.image() : recursive default argument reference Does anyone know what is going on and how I can quit R without losing the contents of my current workspace? I am running R2.0.1 on a windows

Hi I was wondering if there is a permutation test available in R for linear models with continuous dependent covariates. I want to do a test like the one shown here. bmi<-rnorm(100,25) x<-c(rep(0,75),rep(1,25)) y<-rnorm(100)+bmi^(1/2)+rnorm(100,2)*x+bmi*x H0<-lm(y~1+x+bmi) H1<-lm(y~1+x+bmi+x*bmi) anova(H0,H1) summary(lm(y~1+x+bmi)) But I want to use permutation testing to

Hi, The following code, from Angelo Canty article on line "Resampling Methods in R: the boot Package, 2002", works fine for Angelo Canty using R 2.6.0 on Windows XP. It also works for me using R 1.2.1 and S-PLUS 2000 on Windows XP after installing the S-PLUS bootstrap library, with slight differences in my outputs. > library(boot) > library(survival) >

Hi, The following code, from Angelo Canty article on line "Resampling Methods in R: the boot Package, 2002", works fine for Angelo Canty using R 2.6.0 on Windows XP. It also works for me using R 1.2.1 and S-PLUS 2000 on Windows XP after installing the S-PLUS bootstrap library, with slight differences in my outputs. > library(boot) >

Hi, I'm new to R and have a question which seems like it should be easy. I loaded the R port of my boot library and installed it. All of the functions and help files are available but I can't seem to access the data. The data directory was created and contains files with the extension .rda. I tried to use the data() function but I get > data(city) Error: restore file corrupted -- no

I am having a problem using ESS with R. In particular I have large data objects which exceed the 6Mb default heap memory. Outside of ESS I can run R by specifying large values of --vsize and --nsize but I can't figure out how to do this in ESS. Any help would be much appreciated. -- **************************************************** ** Angelo J. Canty **