Displaying 20 results from an estimated 80 matches similar to: "AFTREG weights"
2010 Feb 18
2
Extract p-value from aftreg object
Dear all,
does anyone know how I can extract specific p-values for covariates
from an aftreg object? After fitting a model with aftreg I can find
all different variables by using str(), but there's no place where
p-values are kept. The odd thing is that print() displays them
correctly.
EXAMPLE:
> testdata
start stop censor groupvar var1 var2
1 0 1 0
2010 Nov 25
2
aftreg vs survreg loglogistic aft model (different intercept term)
Hi, I'm estimating a loglogistic aft (accelerated failure time) model, just a
simple plain vanilla one (without time dependent covariates), I'm comparing
the results that I obtain between aftreg (eha package) and survreg(surv
package). If I don't use any covariate the results are identical , if I add
covariates all the coefficients are the same until a precision of 10^4 or
10^-5 except
2011 Nov 17
0
Non-finite finite-difference value" error in eha's, aftreg
This kind of error seems to surprise R users. It surprises me that it doesn't happen much
more frequently. The "BFGS" method of optim() from the 1990 Pascal version of my book was
called the Variable Metric method as per Fletcher's 1970 paper it was drawn from. It
really works much better with analytic gradients, and the Rvmmin package which is an all-R
version that adds bounds
2011 Nov 16
1
"Non-finite finite-difference value" error in eha's aftreg
Hi list!
I'm getting an error message when trying to fit an accelerated failure
time parametric model using the aftreg() function from package eha:
> Error in optim(beta, Fmin, method = "BFGS", control = list(trace =
> as.integer(printlevel)), :
> non-finite finite-difference value [2]
This only happens when adding four specific covariates at the same time
in the
2010 Sep 29
0
eha aftreg overall p-value
Dear useRs,
I am currently fitting an advanced failure time model using G?ran
Brostr?m's excellent "eha" library with the "aftreg" command.
My question: How do I interpret the "Overall p-value", that is
reported at the very bottom of the output? I already figured out it
must be a chi-square test, but I am wondering what a p-value < 0.01
means:
Does it mean
2011 Aug 21
3
pooled hazard model with aftreg and time-dependent variables
Dear R-users,
I have two samples with individuals that are in more than one of the samples
and individuals that are only in one sample. I have been trying to do a
pooled hazard model, stacking one sample below the other, with aftreg and
time-dependent covariates. The idea behind is to see aggregate effects of
covariates, but need to control for ther effects of same individuals in both
samples
2010 Feb 19
1
eha aftreg performance
G?ran, thanks for the update, I'm just about to install it!
Just wanted to drop you a short line about performance (as you once
requested):
aftreg takes ages on my windows machine to calculate a small set of
7 observations which are not even grouped together by "id". To be a
bit more precise, it takes 2:40 mins on my Intel T9300 Core2 Duo @
2.5 GHz. Bigger samples with about 700
2010 Dec 10
1
survreg vs. aftreg (eha) - the relationship between fitted coefficients?
Dear R-users,
I need to use the aftreg function in package 'eha' to estimate failure times for left truncated survival data. Apparently, survreg still cannot fit such models. Both functions should be fitting the accelerated failure time (Weibull) model. However, as G?ran Brostr?m points out in the help file for aftreg, the parameterisation is different giving rise to different
2010 Feb 05
3
AFTREG with ID argument
Dear all,
I have some trouble using the "id"-argument with aftreg (accelerated
failure time regression analysis from the eha library).
As far as I understand it, the id argument is used to group
individuals together if there are time-varying covariates and the
data is arranged in counting process style.
Unfortunately, i cannot figure out how to use the "id"-argument. The
2010 Mar 18
2
Pedigree / Identifying Immediate Family of Index Animal
I have a data frame containing the Id, Mother, Father and Sex from about
10,000 animals in our colony. I am interested in graphing simple family
trees for a given subject or small number of subjects. The basic idea is:
start with data frame from entire colony and list of index animals. I need
to identify all immediate relatives of these index animals and plot the
pedigree for them. We're
2010 May 19
0
how to remove interactions of factor with continuous var
I need to remove certain interactions and keep only the one between the second level of the factor and the continuous var t2
bin4 <- glm(resp2~ t*t2+c5.vrm,data=dfa,family="quasibinomial")
> summary(bin4)
Call:
glm(formula = resp2 ~ t * t2 + c5.vrm, family = "quasibinomial",
data = dfa)
Deviance Residuals:
Min 1Q Median 3Q Max
-6.5464
1999 Apr 02
4
PLATFORMS Update
NAME Douglas Bates
EMAIL bates@stat.wisc.edu
VERSION 0.63.3
PLATFORM i386-unknown-linux
SYSTEM Debian 2.1
CC/FC/MAKE egcs/g77/make
NAME Martyn Plummer
EMAIL plummer@iarc.fr
VERSION 0.63.3
PLATFORM i386-unknown-linux
SYSTEM Redhat 5.1
CC/FC/MAKE gcc/egcs-g77/make
NAME Göran Broström
EMAIL gb@stat.umu.se
VERSION 0.63.3
PLATFORM
2002 Apr 18
0
strptime mysteriously adds a day - 0S-specific: Linux and (PR#1468)
On Thu, 18 Apr 2002 ripley@stats.ox.ac.uk wrote:
> On Thu, 18 Apr 2002, Martin Maechler wrote:
>
> > >>>>> "Jason" == Jason Turner <jasont@indigoindustrial.co.nz> writes:
> >
> > Jason> strptime() mysteriously adds a day to a date, unless the year
> > Jason> is specified. Tested on:
> > Jason> Linux (RedHat
2003 Mar 12
1
'summary' with logicals (PR#2629)
Consider
> oj <- data.frame(x = c(TRUE, FALSE, NA))
> oj
x
1 TRUE
2 FALSE
3 NA
> summary(oj)
x
Mode :logical
FALSE:1
TRUE :1
But
> oj$x <- factor(oj$x)
> summary(oj)
x
FALSE:1
TRUE :1
NA's :1
My point is that NA's should be reported for logicals like they are for
other data types.
Göran
---
Göran
2002 Feb 20
3
Pointer to covariates?
In the first line, use the dist function, found in library mva,
to get the distance between each pair of rows. From this
calculate an incidence matrix for which element i,j is true if
row i in dat equals row j in dat (and false elsewhere).
In the second line, for each row calculate the indices of
the matching rows and take the minimum of those as the key.
incid <-
2011 Sep 09
2
get and save
I have a data frame 'tmp' and a vector 'name' containing 'd2'.
I want to save 'tmp' under the name hidden in 'name', and the file must have
the same name, plus the extension '.rda'.
So I try
> tmp
x y
1 1 3
2 2 4
> name
[1] "d2"
> assign(name, tmp)
> summary(get(name))
x y
Min. :1.00 Min. :3.00
1st
2011 Dec 05
0
ANNOUNCEMENT: Call for Proposals for The R Series from Chapman & Hall/CRC
Chapman & Hall/CRC: The R Series
We are delighted to announce that our new series of books on R is up and running, with two books already published and another nine forthcoming (including three set to publish in 2012). We are keen to receive proposals for books covering all aspects of the development and application of R software. If you have an idea for a book, please contact one of the
2011 May 02
3
ID parameter in model
Hello,
I am apparently confused about the use of an id parameter for an event
history/survival model, and why the EHA documentation for aftreg does
not specify one. All assistance and insights are appreciated.
Attempting to specifiy an id variable with the documentation example
generates an "overlapping intervals" error, so I sorted the original
mort dataframe and set subsequent entry
2011 May 21
1
predict 'expected' with eha package
I am unsure what is being returned, and what is supposed to be
returned, when using 'predict' with "type='expected'" for an aftreg
survival model. The code below first generates a weibull model, then
uses predict to create a vector of the linear predictors, then
attempts to create the 'expected' vector, which is empty. The final
two steps in the code generate a
2010 Jan 28
1
AFT-model with time-varying covariates and left-truncation
Dear Prof. Brostr?m,
Dear R-mailinglist,
first of all thanks a lot for your great effort to incorporate
time-varying covariates into aftreg. It works like a charm so far
and I'll update you with detailled benchmarks as soon as I have them.
I have one more questions regarding Accelerated Failure Time models
(with aftreg):
You mention that left truncation in combination with time-varying