Displaying 20 results from an estimated 20000 matches similar to: "How to extract z value from coxph"
2004 Oct 26
2
vcov method for 'coxph' objects
Dear all,
The help file for the generic function vcov states
"Classes with methods for this function include: 'lm', 'glm', 'nls', 'lme',
'gls', 'coxph' and 'survreg' (the last two in package 'survival')."
Since, I am not able to use vcov.coxph(), I am wondering whether I am
missing something (as I suspect..)
regards,
vito
2004 Oct 06
4
R2.0.0 bug in function vcov in library survival (PR#7266)
Full_Name: Sven Sandin
Version: 2.0.0
OS: SuSE Linux 9.0
Submission from: (NULL) (81.227.17.135)
Have just compiled and installed R-2.0.0.tar.gz running SuSE9.0.
The function vcov do not accept "coxph" object as input any longer.
The same R-program running R1.9.1 do work. R-program attached below.
Exporting the coxph object from R2.0.0 to R1.9.1 I get vcov ouput in R1.9.1.
Exporting
2004 Nov 19
2
function 'vcov' for coxph in R 2.0.0
Hi there,
After I fitted a cox model, I used vcov to obtain the
variance of the parameter estimate. It worked correctly in
R 1.9.1. But it failed in R 2.0.0 and the error message is
Error in vcov(cox.1) : no applicable method for "vcov"
I don't know if it is a bug or there is some update on
this function. Thanks!
Lei Liu
Assistant Professor
Division of Biostatistics and
2013 Feb 14
2
Plotting survival curves after multiple imputation
I am working with some survival data with missing values.
I am using the mice package to do multiple imputation.
I have found code in this thread which handles pooling of the MI results:
https://stat.ethz.ch/pipermail/r-help/2007-May/132180.html
Now I would like to plot a survival curve using the pooled results.
Here is a reproducible example:
require(survival)
require(mice)
set.seed(2)
dt
2006 Feb 16
2
how to retrieve robust se in coxph
Hi,
I am using coxph in simulations and I want to store the "robust se" (or
"se2" in frailty models) for each replicate. Is there a function to retrieve
it, like vcov() for the variance estimate? Thanks!
Lei Liu
Assistant Professor
Division of Biostatistics and Epidemiology
Dept. of Public Health Sciences
School of Medicine
University of Virginia
3181 Hospital West
2013 Nov 14
1
issues with calling predict.coxph.penal (survival) inside a function
Thanks for the reproducable example. I can confirm that it fails on my machine using
survival 2-37.5, the next soon-to-be-released version,
The issue is with NextMethod, and my assumption that the called routine inherited
everything from the parent, including the environment chain. A simple test this AM showed
me that the assumption is false. It might have been true for Splus. Working this
2011 Dec 20
2
Extract BIC for coxph
Dear all,
is there a function similar to extractAIC based on which I can extract the
BIC (Bayesian Information Criterion) of a coxph model?
I found some functions that provide BIC in other packages, but none of them
seems to work with coxph.
Thanks,
Michael
[[alternative HTML version deleted]]
2009 Aug 31
2
How to extract the theta values from coxph frailty models
Hello,
I am working on the frailty model using coxph functions. I am running
some simulations and want to store the variance of frailty (theta)
values from each simulation result. Can anyone help me how to extract
the theta values from the results. I appreciate any help.
Thanks
Shankar Viswanathan
2017 Sep 13
3
vcov and survival
Dear Terry,
Even the behaviour of lm() and glm() isn't entirely consistent. In both cases, singularity results in NA coefficients by default, and these are reported in the model summary and coefficient vector, but not in the coefficient covariance matrix:
----------------
> mod.lm <- lm(Employed ~ GNP + Population + I(GNP + Population),
+ data=longley)
>
2007 May 17
1
MICE for Cox model
R-helpers:
I have a dataset that has 168 subjects and 12 variables. Some of the
variables have missing data and I want to use the multiple imputation
capabilities of the "mice" package to address the missing data. Given
that mice only supports linear models and generalized linear models (via
the lm.mids and glm.mids functions) and that I need to fit Cox models, I
followed the previous
2007 Apr 17
3
Extracting approximate Wald test (Chisq) from coxph(..frailty)
Dear List,
How do I extract the approximate Wald test for the
frailty (in the following example 17.89 value)?
What about the P-values, other Chisq, DF, se(coef) and
se2? How can they be extracted?
######################################################>
kfitm1
Call:
coxph(formula = Surv(time, status) ~ age + sex +
disease + frailty(id,
dist = "gauss"), data = kidney)
2007 Aug 06
1
(Censboot, Z-score, Cox) How to use Z-score as the statistic within censboot?
Dear R Help list,
My question is regarding extracting the standard error or Z-score from a
cph or coxph call. My Cox model is: -
modz=cph(Surv(TSURV,STATUS)~RAGE+DAGE+REG_WTIME_M+CLD_ISCH+POLY_VS,
data=kidneyT,method="breslow", x=T, y=T)
I've used names(modz) but can't see anything that will let me extract
the Z scores for each coefficient or the standard errors in the same
2008 Apr 18
1
Overall p-value from a factor in a coxph fit
Hi all.
If I run the simple regression when x is a categorical variable ( x <-
factor(x) ):
> MyFit <-coxph( Surv(start, stop, event) ~ x )
How can I get the overall p-value on x other than for each dummy
variable?
> anova(MyFit)
does NOT provide that information as previously suggested on the list.
All the best,
Kare
[[alternative HTML version deleted]]
2009 Feb 06
1
Joint test
Dear All,
I am estimating a Cox proportional hazard model, with several interactions
of the type a*z + a*y + a*x + b*z + b*y + b*x.
I need to know if the first three (the "a"s) are jointly significantly
different from the last three (the "b"s). I have tried several approaches,
but have been unsuccessful.
Here's the model, and the code I came up with, with the obvious
2006 Dec 29
2
Survfit with a coxph object
I am fitting a coxph model on a large dataset (approx 100,000 patients), and
then trying to estimate the survival curves for several new patients based
on the coxph object using survfit. When I run coxph I get the coxph object
back fairly quickly however when I try to run survfit it does not come
back. I am wondering if their is a more efficient way to get predicted
survival curves from a coxph
2017 Sep 14
6
vcov and survival
>>>>> Martin Maechler <maechler at stat.math.ethz.ch>
>>>>> on Thu, 14 Sep 2017 10:13:02 +0200 writes:
>>>>> Fox, John <jfox at mcmaster.ca>
>>>>> on Wed, 13 Sep 2017 22:45:07 +0000 writes:
>> Dear Terry,
>> Even the behaviour of lm() and glm() isn't entirely consistent. In both cases,
2011 Sep 12
1
coxreg vs coxph: time-dependent treatment
Dear List,
After including cluster() option the coxreg (from eha package)
produces results slightly different than that of coxph (from survival)
in the following time-dependent treatment effect calculation (example
is used just to make the point). Will appreciate any explaination /
comment.
cheers,
Ehsan
############################
require(survival)
require(eha)
data(heart)
# create weights
2007 Nov 08
2
mapply, coxph, and model formula
Hello -
I am wanting to create some Cox PH models with coxph (in package
survival) using different datasets.
The code below illustrates my current approach and problem with
completing this.
### BEGIN R SAMPLE CODE ##############################
library(survival)
#Define a function to make test data
makeTestDF <- function(n) {
times <- sample(1:200, n, replace = TRUE)
event
2006 Jan 17
2
help with parsing multiple coxph() results
Dear All:
I have a question on using coxph for multiple genes:
I have written code to loop through all 22283 genes in the Hgu-133A and
apply coxph on survival data.
However, I don't know how to work with the result for each gene:
survtest<-coxph(Surv(pcc.primary.stg.3.cox[,'fup_interval'],pcc.primary.stg.
2004 May 16
2
Error in using coxph()
Hi,
I am getting errors of the following kind. I can't
seem to point the source of the error. I would greatly
appreciate any advice.
Many thanks and good day,
-Melinda
Error message :
----------------
"Ran out of iterations and did not converge in:
fitter(X, Y, strats, offset, init, control, weights =
weights,..."
Details :
---------
E is a vector of survival times (or censored