Displaying 20 results from an estimated 700 matches similar to: "Bootstrap BCa confidence limits with your own resamples"
2012 Oct 08
0
Mininum number of resamples required to do BCa bootstrap?
I'm using R 2.15.1 on a 64-bit machine with Windows 7 Home Premium
and package 'boot'.
I've found that using a number of bootstrap resamples in boot() that
is less than the number of data results in a fatal error. Once the
number of resamples meets or exceeds the number of data, the error disappears.
Sample problem (screwy subscripted syntax is a relic of edited down a
more
2012 May 24
1
Issues while using “lift.chart” and “adjProbScore” function from ”BCA” library
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
2007 Jan 26
1
bootstrap bca confidence intervals for large number of statistics in one model; library("boot")
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
2003 Apr 24
1
bca ci's and NaN's in boot.out
Dear All,
I am trying to use the bca.ci function on a boot.out object which consists
a few NaN's and I want to ignore those NaN's, and get a ci
only for the "normal" values.
boot.out$t has R number of values for 3000 different statistics, so when I
use boot.ci(boot.out, index=i) and i happens to be a column in boot.out$t
with some NaN's in there I get an error message. I
2006 Dec 21
4
where is the source code of bca.ci?
i was searching for the source of bca.ci, a function of the package
boot. I tried
require(boot, keep.source=TRUE)
but again the source was not viewable. How should i do?
Best regards
Meinhard Ploner
----------------
PS
> version
_
platform i386-apple-darwin8.8.1
arch i386
os darwin8.8.1
system i386, darwin8.8.1
status
major 2
2010 Aug 16
2
When to use bootstrap confidence intervals?
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
2012 Oct 02
0
Possible error in BCa method for confidence intervals in package 'boot'
I'm using R 2.15.1 on a 64-bit machine with Windows 7 Home Premium.
Sample problem (screwy subscripted syntax is a relic of edited down a
more complex script):
> N <- 25
> s <- rlnorm(N, 0, 1)
> require("boot")
Loading required package: boot
> v <- NULL # hold sample variance estimates
> i <- 1
> v[i] <- var(s) # get sample variance
>
2003 Jan 31
1
Problems with boot package (empinf returns NA)
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
2003 Jul 31
1
namespace magic
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
2010 Aug 01
0
BCa-intervals not defined in boot.ci() for tsboot() -> package: boot
Hello everybody,
when I create an object of class boot with the function tsboot() from the package boot and try to compute several types of confidence intervals with boot.ci("object of class boot created with tsboot") I obtain the warning message, that "BCa-intervals are not defined for time-series bootstraps".
Does that hold in general? Or is it just not defined in
2005 Jan 27
2
[LLVMdev] Building the llvm runtime: 'Can't destroy file: Theprocess cannot access the fi
>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
2011 May 19
2
Separating boot results
Good Morning,
I'm having what I hope to be a simple problem. I am generating bootstrap
confidence intervals using package (boot) - which works perfectly. The issue
I am having is getting the results into a format which I can write out to a
database. To be clear I am having no problems generating the results, I just
need to convert the format of the results such that I can store the results
in
2005 Jan 27
0
[LLVMdev] Building the llvm runtime: 'Can't destroy file: Theprocess cannot access the fi
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
>
2016 Apr 02
0
BCa Bootstrap confidence intervals
Dear R-Experts,
Thanks to Prof. Bonnett, I have got an R script working to calculate confidence intervals around the semipartial correlation coefficients.
Now, I would like to calculate BCa bootstrap CIs using the boot library and the boot.ci(results, type="all") function. How could I modify my R script (here below reproducible example) to get the BCa bootstrap CIs ?
CIsemipartcorr
2011 Feb 16
2
boot.ci error with large data sets
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)
2011 Mar 06
1
bootstrap
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]),
2013 Mar 20
1
Bootstrap (bootSem) causes R to crash
I think we didn't receive this on the list.
--
View this message in context: http://r.789695.n4.nabble.com/Bootstrap-bootSem-causes-R-to-crash-tp4661900p4661944.html
Sent from the R help mailing list archive at Nabble.com.
2004 Feb 11
3
Any help with bootstrapping
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]]
2005 Jan 26
3
[LLVMdev] Building the llvm runtime: 'Can't destroy file: The process cannot access the fi
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?:
2010 Dec 16
1
Arguments in functions
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,