Displaying 20 results from an estimated 100000 matches similar to: "Help in Bootstrapping"
2007 Jun 16
0
Help in HMM commands
Respected Sir,
I am working on Hidden Markov Models for count data. My data
consist of number of new infectives
in a ward per month. I have data for about 50 months. How can I fit a Hidden
Markon Model to my data.
I am using 'repeated' package('hidden' and 'chidden' arguments). I would
like to know how can I estimate
the initial values of the parameters(mu and
2007 Jul 14
1
Installation of a Package
Hi All,
I want to upload J K Lindsey's "repeated" in a LINUX OS..
I had tried the command..
[root@localhost Desktop] # R CMD INSTALL repeated.gz
" WARNING: invalid package 'repeated' "
*Installing to library
'/usr/local/lib/R/library'
ERROR: No packages
2007 Jul 06
1
loading package in LINUX
I am comfortable with windows based R. But recently I had shifted to
LINUX(Red Hat Linux Enterprise Guide 4)
1) I want to load J K Lindsey's repeated library in R. How to install the
packge?
2) How to create the shared library if I ve the fortran codes(I haven't done
creation of shared library in windows also).
I had run the command Rcmd in bin directory but an error message "bash:
2011 Jun 08
1
using stimulate(model) for parametric bootstrapping in lmer repeatabilities
Hi all,
I am currently doing a consistency analysis using an lmer model and
trying to use parametric bootstrapping for the confidence intervals.
My model is like this:
model<-lmer(y~A+B+(1|C/D)+(1|E),binomial)
where E is the individual level for consistency analysis, A-D are
other fixed and random effects that I have to control for.
Following Nakagawa and Scheilzeth I can work out the
2011 May 03
0
Bootstrapping confidence intervals
Hi,
Sorry for repeated question.
I performed logistic regression using lrm and penalized it with pentrace
function. I wanted to get confidence intervals of odds ratio of each
predictor and summary(MyModel) gave them. I also tried to get
bootstrapping standard errors in the logistic regression. bootcov
function in rms package provided them. Then, I found that the confidence
intervals provided by
2011 Mar 19
0
Problems using NLS in conjunction with non-parameteric bootstrapping
Hello,
I have been successfully using nls to fit a non-linear, self-limiting
function to several sets of data collected in 2010 (example found below).
To generate confidence intervals for parameter estimates, I've been
attempting to bootstrap my sample. Unfortunately, I have meet with
singularity gradients and failures to converge. I have altered maxiter and
minFactor statements, used
2012 Jan 06
0
Bootstrapping nlme models
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
2003 Mar 12
1
simulating 'non-standard' survival data
Dear all,
I'm looking for someone that help me to write an R function to simulate
survival data under complex situations, namely time-varying hazard ratio,
marginal distribution of survival times and covariates. The algorithm is
described in the reference below and it should be not very difficult to
implement it. However I tried but without success....;-(
Below there the code that I used; it
2009 May 12
0
Trouble with parametric bootstrap
Hi,
I'm having trouble understanding how to construct a random number generator
for a parametric bootstrap. My aim is to bootstrap a Likelihood Ratio
statistic (under the null) for a linear model. The function at this point
is given by
boot.test.n01 <- function(data, indeces, maxit=20) {
y1 <- fit1+se(e2)*rnorm(314)
mod1 <- glm(y1 ~ X1-1, maxit=maxit)
y2 <-
2007 Feb 21
0
GLS models - bootstrapping
Dear Lillian,
I tried to estimate parameters for time series regression using time
series bootstrapping as described on page 434 in Davison & Hinkley
(1997) - bootstrap methods and their application. This approach is based
on an AR process (ARIMA model) with a regression term (compare also with
page 414 in Venable & Ripley (2002) - modern applied statistics with S)
I rewrote the code
2005 May 20
1
bootstrapping vectors of unequal length
Dear R Help List,
I have a vector of n and a vector of n-1 and I want to use boot() to
bootstrap the ratio of their respective medians. I want to eventually
use boot.ci() to generate confidence intervals. Because the vectors
are not equal in length, I tried a few things, but have yet to be
successful.
Try 1:
> x <- runif(20)
>
> y <- c(runif(19), NA)
>
> median(x)
[1]
2007 Feb 20
1
bootstrapping Levene's test
Hello all,
I am low down on the learning curve of R but so far I have had little
trouble using most of the packages. However, recently I have run into
a wall when it comes to bootstrapping a Levene's test (from the car
package) and thought you might be able to help. I have not been able
to find R examples for the "boot" package where the test statistic
specifically uses a
2006 Oct 10
0
[R-SIG-Finance] regarding bootstrapping... REVISITED
hi Thomas/All,
I went through the thread(
https://stat.ethz.ch/pipermail/r-sig-finance/2006q1/000682.html which
concerns with swaps). Yeah it is correct that i would like to quote both
David and Krishna that the curve interpolation may vary considerably (for
e.g. any polynomial/parametric fit is very different from and curve
fitting whether it is free hand or by NURBS ( complex version of
2013 May 03
1
R package for bootstrapping (comparing two quadratic regression models)
Hello ,
I want to compare two quadratic regression models with non-parametric
bootstrap.
However, I do not know which R package can serve the purpose,
such as boot, rms, or bootstrap, DeltaR.
Please kindly advise and thank you.
Elaine
The two quadratic regression models are
y1=a1x^2+b1x+c1
y1= observed migration distance of butterflies()
y2=a2x^2+b2x+c2
y2= predicted migration distance of
2009 Mar 19
0
Testing loess fit versus linear fit.
I would like to experiment with testing the fit of a loess model against
the fit from an ordinary linear regression. The 1988 JASA paper by
Cleveland and Devlin *appears* to indicate that this can be done, at
least ``approximately''. They, as I read it, advocate the use of an
ANOVA type test with degree of freedom chosen to make the ``F ratio''
have an approximate F distribution
2007 May 27
1
Parametric bootstrapped Kolmogorov-Smirnov GoF: what's wrong
Dear R-users,
I want to perform a One-Sample parametric bootstrapped Kolmogorov-Smirnov
GoF test (note package "Matching" provides "ks.boot" which is a 2-sample
non-parametric bootstrapped K-S version).
So I wrote this code:
---[R Code] ---
ks.test.bootnp <- function( x, dist, ..., alternative=c("two.sided", "less",
"greater"), B = 1000 )
{
2006 Feb 27
1
Different deviance residuals in a (similar?!?) glm example
Dear R-users,
I would like to show you a simple example that gives an overview of one
of my current issue.
Although my working setting implies a different parametric model (which
cannot be framed in the glm), I guess that what I'll get from the
following example it would help for the next steps.
Anyway here it is.
Firstly I simulated from a series of exposures, a series of deaths
(given a
2006 Oct 02
0
GLS models - bootstrapping
Hello,
I am have fitted GLS models to time series data. Now I wish to bootstrap
this data to produce confidence intervals for the model.
However, because this is time series data, normal bootstrapping is not
applicable. Secondly, 'tsboot' appears to only be useful for ar models -
and does not seem to be applicable to GLS models.
I have written code in R to randomly sample blocks of
2003 Jan 07
1
help interpreting output?
Dear R experts,
I'm hoping someone can help me to interpret the results of building
gam's with mgcv in R.
Below are summaries of two gam's based on the same dataset. The first
gam (named "gam.mod") has six predictor variables. The second gam
(named "gam.mod2") is exactly the same except it is missing one of the
predictor variables. What is confusing me is
2010 Nov 11
0
bootstrap/boot unknown distribution
Hi, this is a question about bootstrapping, it relates more to the concept
than to the R package boot. But I wonder below if boot can help me. I have
the below to calculate a certain point estimate:
estimate= (0.9 * 0.03 * 700000 *
(((77 * (76 / 76.0)) / 83107) -
((174 * (154 / 154.0)) / 376354)))
= 8.77311
Now I want to calculate confidence intervals around that estimate so I
thought that