On Dec 9, 2009, at 9:05 AM, Trafim Vanishek wrote:
I missed number of bootstrap replicates R
boot(Reg, bootcoeff, R=10)
but still it doesn't work
Error in statistic(data, original, ...) : unused argument(s)
(original)
On Wed, Dec 9, 2009 at 2:46 PM, Trafim Vanishek
rdapam...@gmail.com
Hello,
We are a group of PhD students working in the field of toxicology. Several
of us have small data sets with N=10-15. Our research is mainly about the
association between an exposure and an effect, so preferrably we would like
to use linear regression models. However, most of the time our
John Fox has a nice explanation here:
http://cran.r-project.org/doc/contrib/Fox-Companion/appendix-bootstrapping.pdf
-Ista
On Wed, Oct 21, 2009 at 6:38 AM, Charlotta Rylander z...@nilu.no wrote:
Hello,
We are a group of PhD students working in the field of toxicology. Several
of us have
Hi,
I am trying to run some bootstraps with the boot package. When I run
it with 400 replicates it does it ok, but then I need to run the same
analysis but with 89, 86, 102 and 106 samples (for four different
environments), and then is when I get the error message:
mybootstrap -
Hello,
I've started using R few months ago and I really like it.
I need to estimate standard deviation of certain statistics (some
measures of poverty). I found a really simple program, and I just need
to check whether it's OK and really calculates what it's supposed to.
Let's suppose e.
-help-boun...@r-project.org [mailto:r-help-boun...@r-
project.org] On Behalf Of Thomas Mang
Sent: Thursday, January 29, 2009 3:52 PM
To: r-h...@stat.math.ethz.ch
Subject: Re: [R] bootstrapping in regression
Greg Snow wrote:
What you are describing is actually a permutation test rather than
On Fri, 30 Jan 2009, Stephan Kolassa wrote:
Hi Thomas,
Thomas Mang schrieb:
I have a question here: I am not sure if I understand your 'fit the full
model ... to the permuted data set'. Am I correct to suppose that once the
residuals of the reduced-model fit have been permuted and added
On Jan 31, 2009, at 1:27 PM, Charles C. Berry wrote:
On Fri, 30 Jan 2009, Stephan Kolassa wrote:
Hi Thomas,
Thomas Mang schrieb:
I have a question here: I am not sure if I understand your 'fit
the full
model ... to the permuted data set'. Am I correct to suppose that
once the
Hi Thomas,
Thomas Mang schrieb:
I have a question here: I am not sure if I understand your 'fit the full
model ... to the permuted data set'. Am I correct to suppose that once
the residuals of the reduced-model fit have been permuted and added back
to the fitted values, the values obtained
Hi,
Please apologize if my questions sounds somewhat 'stupid' to the trained
and experienced statisticians of you. Also I am not sure if I used all
terms correctly, if not then corrections are welcome.
I have asked myself the following question regarding bootstrapping in
regression:
Say for
On 1/29/2009 11:43 AM, Thomas Mang wrote:
Hi,
Please apologize if my questions sounds somewhat 'stupid' to the trained
and experienced statisticians of you. Also I am not sure if I used all
terms correctly, if not then corrections are welcome.
I have asked myself the following question
Tom Backer Johnsen wrote:
Thomas Mang wrote:
Hi,
Please apologize if my questions sounds somewhat 'stupid' to the
trained and experienced statisticians of you. Also I am not sure if I
used all terms correctly, if not then corrections are welcome.
I have asked myself the following question
: [R] bootstrapping in regression
Hi,
Please apologize if my questions sounds somewhat 'stupid' to the
trained
and experienced statisticians of you. Also I am not sure if I used all
terms correctly, if not then corrections are welcome.
I have asked myself the following question regarding
Greg Snow wrote:
What you are describing is actually a permutation test rather than a bootstrap
(related concepts but with a subtle but important difference).
The way to do a permutation test with multiple x's is to fit the reduced model
(use all x's other than x1 if you want to test x1) on
Hi all,
i am relatively new to R. I searched all relevant CRAN taks views, in
particular finance and time series but could not find any package that
covers a function for bootstrapping skewness-adjusted t-statistics (Johnson
1978). Did I miss something? any help is highly appreciated.
thanks
Dear all,
I am trying to bootstrap predictions from gnls models using the following code:
# a is the dataframe with which I am working; it contains the variables
# response.variable,LD,L,G,P and F
###
model=gnls(response.variable ~ a * LD/(b + LD),
params = list(a + b ~ L), start =
On Fri, 7 Nov 2008, Christoph Scherber wrote:
Dear all,
I am trying to bootstrap predictions from gnls models using the following
code:
# a is the dataframe with which I am working; it contains the variables
# response.variable,LD,L,G,P and F
And without it your code is not reproducible.
Dear all,
Here comes a reproducible example, with the original data added.
The error message when running boot() is:
Error in gnls(response.variable ~ a * LD/(b + LD), params - list(a + :
Step halving factor reduced below minimum in NLS step
boot() in this case only seems to work for very
Subject: RE: [R] bootstrapping - number of items to replace is not a
multiple of replacement length
Hello,
Your theta() function is returning different
sets of coefficients depending on the results of
step().
You'll need to add code to theta() to figure
out which variables were selected
Hello,
I'm new to boostrapping and I'd need some help to understand the error
message that pops up when I run my script.
I have a data.frame with 73 lines and 21 column.
I am running a stepwise regression to find the best model using the R
function step.
I apply bootstrapping to obtain model
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]
On Behalf Of Gabriela Bucini
Sent: Tuesday, September 09, 2008 5:02 PM
To: r-help@r-project.org
Subject: [R] bootstrapping - number of items to replace is not a
multiple
ofreplacement length
Hello,
I'm new
HiI would like to use the parametric bootstrap confidence intervals. The
problem is that I am using a step stress model based on a gamma distributed
data. So, first I need to generate a spacial data and then find the MLE`s then
I must find the bootstrap confidence interval.I dont know how to
Dear list,
sorry for asking a more statistical question. I have been reading on
penalyzing estimates of regression and bootstrapping regression,
trying to include both or either in my analysis. But it is not clear
to me (mainly due to my non-statistics background) whether they aim to
do
DAVID ARTETA GARCIA wrote:
Dear list,
sorry for asking a more statistical question. I have been reading on
penalyzing estimates of regression and bootstrapping regression,
trying to include both or either in my analysis. But it is not clear
to me (mainly due to my non-statistics
Hello all:
Just wondering if I can get advice on what kind of
bootstrapping I should use when using a regression
model to estimate juvenile fish passage data. I use
rotary screw traps to do fish mark-recapture trials
and the efficiency of every trial is added to the
graph generating a different
On 2/24/2008 4:03 PM, Felipe Carrillo wrote:
Hello all:
Just wondering if I can get advice on what kind of
bootstrapping I should use when using a regression
model to estimate juvenile fish passage data. I use
rotary screw traps to do fish mark-recapture trials
and the efficiency of every
Dear friends,
I'm interested in obtaining bootstrapped standard errors for a model that I'm
estimating. I do realize that i can use the sample command and do the bootstrap
by hand. But I was hoping somebody can help me on how to use the boot
package.
The model is as follows
# Likelihood
Hi, I am trying to get 95% CI s around a quantile growth curve, but
my result looks strange to me.
Here is the function I defined myself
boot.qregress-function(mat1, group, quantile, int, seed.1){
boot.fit-NULL
set.seed(seed.1)
for (i in 1:int){
Two follow up questions from post regarding bootstrapping contrasts
for a RM ANOVA:
1. Because my data are repeated measures, isn't it true that I want to
shuffle my column heading individually for each subject (row) by
resampling WITHOUT replacement?
2. For my DV (latency) I have 3 columns of
On Mon, Oct 15, 2007 at 11:19:35PM -0500, Alex Baugh wrote:
However, I don't know where to begin to write a program to do
contrasts with a resampling technique.
select a random sample (with replacement) from the population with
factor level 1, and a random sample from the population with
I have executed a Repeated Measures ANOVA with one DV (latency) and
one within subject factor (acoustic condtion: 3 levels) by
bootstrapping my sampling distribution of F from the empirical sample
distribution. I chose to resample because the sample distribution
deviates from normality a lot.
The
101 - 131 of 131 matches
Mail list logo
