similar to: Separating boot results

Hello, I have a question regarding bootstrap confidence intervals. Suppose we have a data set consisting of single measurements, and that the measurements are independent but the distribution is unknown. If we want a confidence interval for the population mean, when should a bootstrap confidence interval be preferred over the elementary t interval? I was hoping the answer would be

I like to bootstrap regression models, saving the entire set of bootstrapped regression coefficients for later use so that I can get confidence limits for a whole set of contrasts derived from the coefficients. I'm finding that ordinary bootstrap percentile confidence limits can provide poor coverage for odds ratios for binary logistic models with small N. So I'm exploring BCa confidence

I'm confused about name spaces. This morning I installed the boot package because I wanted to look at bca.ci. So I did library(boot), but then I had, > bca.ci Error: Object "bca.ci" not found I had a look in the boot R directory and bca.ci was there as expected. So then I took a look at the NAMESPACE file for the boot package and saw that bca.ci wasn't exported. I tried

>From: Jeff Cohen Date: Wed, 26 Jan 2005 19:47:44 -0800 > >Fixed. Yes, now it isn't the path. I've recorded this trace: ------------------------- llvm[3]: Building Debug Bytecode Archive libc.bca /bin/rm -f /C/projects/build/MinGW/llvm-4-1/Debug/lib/libc.bca /C/projects/build/MinGW/llvm-4-1/Debug/bin/llvm-ar rcsf /C/projects/build/MinGW/llvm-4-1/Debug/lib/libc.bca

Hi all, I am trying to convert a data set of physician death codings (each individual's cause of death is coded by multiple physicians) from long to wide format, but the "reshape" function doesn't seem to work because it requires a "time" variable to identify the sequence among the repeated observations within individuals. My data set has no order, and different

---------- Forwarded message ---------- From: alis villiyam <aalisiyan at gmail.com> Date: Mon, Jul 27, 2009 at 9:47 AM Subject: randomized block design analysis in R To: bolker at zoology.ufl.edu Dear All user Hello, I'm a student and I have some trouble with the experimental (columns-experiments) design of my project. I use a randomized block design with 4 treatments including a

On Thu, 2005-01-27 at 13:16, Henrik Bach wrote: > c:\projects\build\MinGW\llvm-4-1\Debug\bin\llvm-ar.exe: > c:/projects/build/MinGW/llvm-4-1/Debug/lib/libc.bca-000000: Can't destroy > file (hb:2): The process cannot access the file because it is being used by > another process. > make[3]: *** [/C/projects/build/MinGW/llvm-4-1/Debug/lib/libc.bca] Error 2 >

Hello, I have two different dataset, and wanted to join the two. For example I have a table of codes of cities, and other with with the codes of travels, [source for the destine]. what he wanted was to have a new data.frame with all the information city<-data.frame(city="Barcelona",cod=1) city<-rbind(city,data.frame(city="Madrid",cod=2))

Sometimes one might like to obtain pointwise bootstrap bias-corrected, accelerated (BCA) confidence intervals for a large number of statistics computed from a single dataset. For instance, one might like to get (so as to plot graphically) bootstrap confidence bands for the fitted values in a regression model. (Example: Chiu S et al., Early Acceleration of Head Circumference in Children with

Dear List, Couple of issues while using functions from ?BCA? library: 1. I am trying to use ?lift.chart? function from ?BCA? library, but facing issues while using model where model formula is passed as formula object in glm. When model formula is written as text, then it works fine. In my case input variables and target variables are going to change dynamically, so have to used formula as

Dear List I have run into some problems with boot.ci from package boot. When I try to obtain a confidence interval of type bca, boot.ci() returns the following error when the data set i large: Error in bca.ci(boot.out, conf, index[1L], L = L, t = t.o, t0 = t0.o, : estimated adjustment 'a' is NA Below is an example that produces the above mentioned error on my machine. library(boot)

In the boot package,consider a scalar function to boot. > estimator <- function(x, d) { + mean(x[d]) + } > > data <- city$u > b <- boot(data, estimator, R=1000) > b$t0 [1] 64 > ci <- boot.ci(b, type=c("bca"), conf=.95) > ci$bca conf [1,] 0.95 49.44 991.39 36.78807 110.0254 Now if I want estimators to return a vector,E.g. it's {c(mean(x[d]),

Could someone help me on how to correctly try to correct this error message arning : BCa Intervals used Extreme Quantiles Some BCa intervals may be unstable Warning message: Extreme Order Statistics used as Endpoints in: norm.inter(t, adj.alpha) Regards IF [[alternative HTML version deleted]]

Hi Jeff and others, When building the llvm runtime, I always get this error message: 'Can't destroy file: The process cannot access the file because it is being used by another process.' The file is destoyed anyway. I think that the the real error is the path for the file (*/\file.tmp). However, I can't find the bug in the source. Do you have any clue?:

Hi, I'm looking to combine two data frames. Several of the columns are in common while the others need to be summed up. The apply functions and the merge functions don't seem to be working. I've included a basic example of what I'm trying to do below. Thanks! Sean data.frame1<-as.data.frame(matrix(c('winter','dredge','515',100,150),1,5))

Hello, I'm not much of a programmer, and am trying to understand the workings of the function below called "RStatFctn" within this bootstrap procedure. RStatFctn is defined to have two arguments: "x", intended to be a data vector; and "d" intended to be an index (or so it looks to me). Later, "rnormdat" is created to be the data vector. However,

Hello, I have tried to find this out some other way, but unsuccessful I have to try this list. I assume this should be quite simple. I have a dataset with 4 columns, "Sample_no", "Species", "Nitrogen", "Carbon" in csv format. In the species column I have many different species with varying number of obs per species Eg "Sample_no"

I have some specs that involve the use of eval and class definitions to test code generation. I want to always start with a clean slate so none of my tests fail or succeed incorrectly due to artifacts left over from previous specs. Example of my situation Spec 1 defines class Fish class Cod < Fish Spec 2 defines class Animal class Cod < Animal In this situation the

Hi I'm using boot package for some analysis on linear regression coeficients. My problem is that I can not compute bca intervals, I get an error message > bca.ci(blm8901,index=1) Error in if (!all(rk > 1 & rk < R)) warning("Extreme Order Statistics used as Endpoints") : missing value where logical needed The problem is the empinf.reg function that is

I tried to reproduce a result from a former colleague which he got with S-plus bootstrap method. I don't have S-plus at hand. In R, there are 2 packages related to bootstrap method, bootstrap and boot. The former has a function called 'bootstrap' but this does not seem to conform either to the function used in S-plus nor to that described in MASS, 3d ed., p.144. The latter seems to be