Displaying 20 results from an estimated 5000 matches similar to: "Function comparable to cutpt.coxph from "Survival Analysis using S""
2011 Jan 21
3
Function comparable to cutpt.coxph from "Survival Analysis using S"
Dear Mrs Rachel Pearce,
I am looking for a function "cutpt-coxph" in R - like you did some years ago.
How have you solved the problem? Have you found it or a similar function?
thank you, Sincerely, Friederike
"The title says it all really; I am looking for a function along the lines of
cutpt.coxph as described in "Survival Analysis Using S" (Tableman and
Kim), Chapter
2005 Sep 19
2
Problem with tick marks in lines.survfit (package survival)
I have attempted to follow posting guidelines but I have failed to find out
what I am doing wrong here.
I am trying to use lines.survfit to plot a second curve onto a survival
curve produced by plot.survfit. In my case this is to be a progression free
survival curve superimposed upon an overall survival curve, but I will
illustrate my problem using the example given in the help for
2005 Mar 17
1
Legend positioning in scaled survival plot
I am sorry that this is another novice question. I am having trouble
using "legend" with the survival curve plot from the survival package,
and I wonder if it is because I have rescaled my plot.
Here is the relevant segment of code:
> plot(survfit(Surv(OS,Status)~shortishcr1),main='Overall Survival by
factor',
+ xlab='Years',ylab='%
2011 Jul 10
1
Package "survival" --- Difference of coxph strata with subset?
[code]>require("survival")
> coxph(Surv(futime,fustat)~age + strata(rx),ovarian)
Call:
coxph(formula = Surv(futime, fustat) ~ age + strata(rx), data = ovarian)
coef exp(coef) se(coef) z p
age 0.137 1.15 0.0474 2.9 0.0038
Likelihood ratio test=12.7 on 1 df, p=0.000368 n= 26, number of events= 12
> coxph(Surv(futime,fustat)~age, ovarian, subset=rx==1)
2010 Dec 02
0
survival - summary and score test for ridge coxph()
It seems to me that summary for ridge coxph() prints summary but returns NULL. It is not a big issue because one can calculate statistics directly from a coxph.object. However, for some reason the score test is not calculated for ridge coxph(), i.e score nor rscore components are not included in the coxph object when ridge is specified. Please find the code below. I use 2.9.2 R with 2.35-4 version
2009 Sep 26
1
Multiple comparisons for coxph survival analysis model
Hello, all R-users!
I am working on fitting a survival analysis model using the coxph
function for Cox proportional hazards regression model. Data look like
usual:
==========================
group block death censor
Group1 1 4 1
Group1 1 12 1
...
Group2 30 4 1
Group2 30 4 1
...
Group3 57 16
2009 Jul 13
0
adjusting survival using coxph
I have what I *think* should be a simple problem in R, and hope
someone might be able to help me.
I'm working with cancer survival data, and would like to calculate
adjusted survival figures based on the age of the patient and the
tumour classification. A friendly statistician told me I should use
Cox proportional hazards to do this, and I've made some progress with
using the
2008 Jun 07
1
expected risk from coxph (survival)
Hello,
When I try to to obtain the expected risk for a new dataset using coxph in the survival package I get an error. Using the example from ?coxph:
> test1 <- list(time= c(4, 3,1,1,2,2,3),+ status=c(1,NA,1,0,1,1,0),+ x= c(0, 2,1,1,1,0,0),+ sex= c(0, 0,0,0,1,1,1))> cox<-coxph( Surv(time, status) ~ x + strata(sex), test1)
2007 Nov 21
0
survest and survfit.coxph returned different confidence intervals on estimation of survival probability at 5 year
I wonder if anyone know why survest (a function in Design package) and
standard survfit.coxph (survival) returned different confidence
intervals on survival probability estimation (say 5 year).
I am trying to estimate the 5-year survival probability on a continuous
predictor (e.g. Age in this case). Here is what I did based on an
example in "help cph". The 95% confidence intervals
2012 May 07
1
estimating survival times with glmnet and coxph
Dear all,
I am using glmnet (Coxnet) for building a Cox Model and
to make actual prediction, i.e. to estimate the survival function S(t,Xn) for a
new subject Xn. If I am not mistaken, glmnet (coxnet) returns beta, beta*X and
exp(beta*X), which on its own cannot generate S(t,Xn). We miss baseline
survival function So(t).
Below is my code which takes beta coefficients from
glmnet and creates coxph
2006 May 07
1
model selection, stepAIC(), and coxph() (fwd)
Hello,
My question concerns model selection, stepAIC(), add1(), and coxph().
In Venables and Ripley (3rd Ed) pp389-390 there is an example of using
stepAIC() for the automated selection of a coxph model for VA lung cancer
data.
A statistics question: Can partial likelihoods be interpreted in the same
manner as likelihoods with respect to information based criterion and
likelihood ratio tests?
2011 Oct 01
4
Is the output of survfit.coxph survival or baseline survival?
Dear all,
I am confused with the output of survfit.coxph.
Someone said that the survival given by summary(survfit.coxph) is the
baseline survival S_0, but some said that is the survival S=S_0^exp{beta*x}.
Which one is correct?
By the way, if I use "newdata=" in the survfit, does that mean the survival
is estimated by the value of covariates in the new data frame?
Thank you very much!
2005 Sep 07
1
Survival analysis with COXPH
Dear all,
I would have some questions on the coxph function for survival analysis,
which I use with frailty terms.
My model is:
mdcox<-coxph(Surv(time,censor)~ gender + age + frailty(area, dist='gauss'),
data)
I have a very large proportion of censored observations.
- If I understand correctly, the function mdcox$frail will return the random
effect estimated for each group on the
2012 Aug 08
1
basehaz() in package 'Survival' and warnings() with coxph
Hello,
I have a couple of questions with regards to fitting a coxph model to a data
set in R:
I have a very large dataset and wanted to get the baseline hazard using the
basehaz() function in the package : 'survival'.
If I use all the covariates then the output from basehaz(fit), where fit is
a model fit using coxph(), gives 507 unique values for the time and the
corresponding cumulative
2010 Feb 16
1
survival - ratio likelihood for ridge coxph()
It seems to me that R returns the unpenalized log-likelihood for the ratio likelihood test when ridge regression Cox proportional model is implemented. Is this as expected?
In the example below, if I am not mistaken, fit$loglik[2] is unpenalized log-likelihood for the final estimates of coefficients. I would expect to get the penalized log-likelihood. I would like to check if this is as expected.
2010 Apr 20
3
Help: coxph() in {survival} package
Hi All,
I'm runnning coxph() on 90 different datasets (in a loop).
1. I'm wondering how can I get "log-likelihood" value from coxph() output.
Currently I can only see following:
Likelihood ratio test =
Wald test =
Score (logrank) test =
2. Once I have likelihood value, I would like to extract these from R
output (for each data set).
Can any one help please, thanks in
2005 Oct 26
0
Survival analysis with COXPH
Dear all,
I use the COXPH function in the SURVIVAL package to estimate survival models
with a random effect.
I would like to know if there is a measure of "model fit and complexity"
analogous to the Akaike Information Criterion implemented in COXPH, in order
to compare together models including different sets of covariates (models
not necessarily nested within each others).
Kind
2012 Jan 24
1
Plotting coxph survival curves
Hi,
I am attempting to plot survival curves estimated by cox proportional
hazards regression model. The formula for the model is this:
F.cox.weight <- coxph(Surv(Lifespan, Status) ~ MS + Weight + Laid + MS:Laid
+ Weight:Laid, data = LongF)
MS = Mating status (mated/virgin)
Weight = adult female weight, continuous covariate
Laid = number of eggs laid by each female, continuous covariate
I
2011 May 11
2
changes in coxph in "survival" from older version?
Hi all,
I found that the two different versions of "survival" packages, namely 2.36-5
vs. 2.36-8 or later, give different results for coxph function. Please see
below and the data is attached. The second one was done on Linux, but Windows
gave the same results. Could you please let me know which one I should trust?
Thanks,
...Tao
#####============================ R2.13.0,
2001 Sep 18
1
case weights in coxph (survival)
Hi,
I am having trouble with the survival library, particualrily the coxph
function.
the following works
coxph(jtree9$cph.call,z,rep(1,dim(z)[1]))
Call:
coxph(formula = jtree9$cph.call, data = z, weights = rep(1, dim(z)[1]))
coef exp(coef) se(coef) z p
SM 0.2574 1.294 0.0786 3.274 1.1e-03
Sex -0.1283 0.880 0.1809 -0.709