Displaying 20 results from an estimated 30000 matches similar to: "simple list question (question withdrawn)"
2008 Dec 13
1
simple list question
I'd appreciate some tips, I'm making a simple mistake trying to
extract elements from a list of fit objects.
The following command works, coef( cph.list[[1]] ) ,.... coef(
cph.list[[3]] ) and so forth. These extract regression coefficients
from the appropriate list element.
When I try to run this inside a for loop, or an lapply
(lapply(cph.list,coef)) I get this error
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
2007 Feb 15
1
bootcov and cph error
Hi all,
I am trying to get bootstrap resampled estimates of covariates in a Cox
model using cph (Design library).
Using the following I get the error:
> ddist2.abr <- datadist(data2.abr)
> options(datadist='ddist2.abr')
> cph1.abr <- cph(Surv(strt3.abr,loc3.abr)~cov.a.abr+cov.b.abr,
data=data2.abr, x=T, y=T)
> boot.cph1 <- bootcov(cph1.abr, B=100, coef.reps=TRUE,
2009 Feb 17
1
Processing a list of fit objects
Hi, I have a list of fit objects (fit objects from HMISC functions)
I create elements in the list in this way
lrm.sumtot <- lrm( ae7bepn ~ trarm + sumtot , data=sd.fix)
lrm.list[['lrm.sumtot']] <- lrm.sumtot
And I can run (anova(lrm.sumtot))
The following also gives the anova I'd expect
zz <- lrm.list[['lrm.sumtot']];anova(zz)
And similarly for the summary
2004 Mar 30
0
koq.q ---- Kent O' Quigley R2
Dear R-users,
I apply to your kind attention to know if someone have used the Splus software
koq.q (Kent & O'Quigley's measure of dependence for censored data) in R and
kindly can help me.
I have tried several times to contact the authors Andrej Blejec
(andrej.blejec at uni-lj.si) or Janez Stare (janez.stare at mf.uni-lj.si) but
unfortunately no one answered me.
Following
2010 Aug 05
3
How to extract se(coef) from cph?
Hello,
I am modeling some survival data wih cph (Design). I have modeled a predictor
which showed non linear effect with restricted cubic splines. I would like to
retrieve the se(coef) for other, linear, predictors. This is just to make nice
LateX tables automatically. I have the coefficients with coef().
How do I do that?
Thanks,
David Biau.
[[alternative HTML version deleted]]
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
2011 Feb 21
2
Interpreting the example given by Prof Frank Harrell in {Design} validate.cph
Dear R-help,
I am having a problem with the interpretation of result from validate.cph in
the Design package.
My purpose is to fit a cox model and validate the Somer's Dxy. I used the
hypothetical data given in the help manual with modification to the cox
model fit. My research problem is very similar to this example.
This is the model without stratification:
> library(Design)
> f1
2011 Feb 19
0
contrasting Somer's D from Design package
Dear R help,
I am having a problem with the Design package and my problem is detailed
here.
I fit a cox model to my data and validate the Somer's Dxy using the Design
package.
(Because of computation time problem, i only try 10 bootstrap samples for
the time being)
This is the model without stratification:
> library(Design)
>
2004 Apr 21
1
difference between coxph and cph
Hi. I am using Windows version of R 1.8.1. Being somewhat new to survival
analysis, I am trying to compare cph (Design) with coxph (survival) for use
with a survival data set.
I was wondering why cph and coxph provide me with different confidence
intervals
for the hazard ratios for one of the variables. I was wondering if I am
doing something wrong? Or if the two functions are calculating hazard
2011 Mar 07
0
survest() for cph() in Design package
Hi, I am trying to run a conditional logistic model on a nested case-control
study using cph() and then estimate survival based on the model. The data came
from Prof Bryan Langholz website where he also has the SAS code to this, so I am
trying to replicate the SAS results.
The data attached. Basically, the variables are:
rstime: risk set age
rsentry: fake entry time, just before rstime
setno:
2007 Aug 27
2
validate (package Design): error message "subscript out of bounds"
Dear R users
I use Windows XP, R2.5.1 (I have read the posting guide, I have
contacted the package maintainer first, it is not homework).
In a research project on renal cell carcinoma we want to compute
Harrell's c index, with optimism correction, for a multivariate
Cox regression and also for some univariate Cox models.
For some of these univariate models I have encountered an error
2008 Sep 29
0
nomogram function (design library)
Dear colleagues,
I hope someone can help me with my problem.
I have fitted a cox model with the following syntax:
# cox01def <-cph(Surv(TEVENT,EVENT) ~ ifelse(AGE>50, (AGE-50)^2,0) +
BMI +
# HDL+DIABETES +HISTCAR2 + log(CREAT)+
as.factor(ALBUMIN)+STENOSIS+IMT,data # = XC, x=T, y=T, surv=T) *1
Furthermore I have estimated my beta's also with a Lasso method -
Coxpath ( from
2004 Dec 15
2
using Hmisc and Design library
Hi, I encountered a weird problem when using the
Design and Hmisc problem. I have 2 data frame called
"a" and "b", both have 3 columns: "time", "status" and
"scores", a sample of the data frame is like:
data frame "a":
time status scores
1 21 1 99.61
2 38 0 101.11
3 51 0 100.62
4 48 0 87.52
5 78 0
2011 Nov 30
0
formula for calculating the survival probability for nomogram
Hi, I used Dr. Harrell's rms package to make a nomogram.
Below is my code for nomogram and calculate total points and probability *in
original data set* used for building the nomogram. *My question is how I get
the formula for calculating the survival probability for this nomogram. Then
I can use this formula to do validation by using other data set. *
f1 <- cph(Surv(retime,dfs) ~
2024 Sep 22
2
store list objects in data.table
Thanks everyone for their responses.
My data is organized in a data.table.? My goal is to perform analyses
according to some groups.? The results of analysis are objects.? If
these objects could be stored as elements of a data.table, this would
help downstream summarizing of results.
Let me try another example.
carsdt <- setDT(copy(mtcars))
carsdt[, unique(cyl) |> length()]
#[1] 3
2004 Dec 15
0
Re: [S] using Hmisc and Design library
sorry, I had a typo there, it's datadist(b) for the
analysis of data frame "b".
--- Robert Balshaw <Robert.Balshaw at syreon.com> wrote:
> Not sure if this will help, but did you mean to use
> datadist(a) for
> the analysis of B?
>
> Rob
>
> > -----Original Message-----
> > From: r-help-bounces at stat.math.ethz.ch
> >
2008 Feb 12
1
Namespace/method oddity
I stumbled on the following:
> library(stats4)
> example(mle)
> confint.default(fit2)
Error in UseMethod("vcov") : no applicable method for "vcov"
In addition: Warning message:
In object$coefficients :
$ operator not defined for this S4 class, returning NULL
> vcov(fit2)
lymax lxhalf
lymax 0.02857612 -0.04870231
lxhalf -0.04870231 0.11457338
2005 Mar 15
2
Lemon drops
I bumped into the following situation:
Browse[1]> coef
deg0NA deg4NA deg8NA deg0NP deg4NP deg8NP
(Intercept) 462 510 528 492 660 762
Browse[1]> coef[,1]
[1] 462
Browse[1]> coef[,1,drop=F]
deg0NA
(Intercept) 462
where I really wanted neither, but
(Intercept)
462
Anyone happen to know a neat way out of the conundrum?
I can think of
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