Displaying 20 results from an estimated 1000 matches similar to: "Competing risks adjusted for covariates"
2009 Mar 25
2
Competing risks Kalbfleisch & Prentice method
Dear R users
I would like to calculate the Cumulative incidence for an event
adjusting for competing risks and adjusting for covariates. One way to
do this in R is to use the cmprsk package, function crr. This uses the
Fine & Gray regression model. However, a simpler and more classical
approach would be to implement the Kalbfleisch & Prentice method (1980,
p 169), where one fits cause
2009 May 20
1
turning off specific types of warnings
Dear R users,
I have a long function that among other things uses the "survest" function from the Design package. This function generates the warning:
In survest.cph (...)
S.E. and confidence intervals are approximate except at predictor means.
Use cph(...,x=T,y=T) (and don't use linear.predictors=) for better estimates.
I would like to turn this specific warning off, as it
2010 Apr 14
5
Running cumulative sums in matrices
Dear R-helpers,
I have a huge data-set so need to avoid for loops as much as possible. Can someone think how I can compute the result in the following example (that uses a for-loop) using some version of apply instead (or any other similarly super-efficient function)?
example:
#Suppose a matrix:
m1=cbind(1:5,1:5,1:5)
#The aim is to create a new matrix with every column containing the
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
2006 Aug 17
1
putting the mark for censored time on 1-KM curve or competing risk curve
Hi All,
I'm trying to figure out the cumulative incidence curve in R in some
limited time. I found in package "cmprsk", the command "plot.cuminc" can
get this curve. But I noticed that there is no mark for the censored
time there, comparing with the KM curve by "plot.survfit". Here are my
codes (attached is the data):
----------------
2009 Aug 02
1
Competing Risks Regression with qualitative predictor with more than 2 categories
Hello,
I have a question regarding competing risk regression using cmprsk package (function crr()). I am using R2.9.1. How can I do to assess the effect of qualitative predictor (gg) with more than two categories (a,b,c) categorie c is the reference category. See above results, gg is considered like a ordered predictor !
Thank you for your help
Jan
> # simulated data to test
> set.seed(10)
2007 Sep 25
7
Who uses R?
Dear R users,
I have started work in a Statistics government department and I am trying to
convince my bosses to install R on our computers (I can't do proper stats in
Excel!!). They asked me to prove that this is a widely used software (and not
just another free-source, bug infected toy I found on the web!) by suggesting
other big organisations that use it. Are you aware of any reputable
2011 Jun 27
7
cumulative incidence plot vs survival plot
Hi, I am wondering if anyone can explain to me if cumulative incidence (CI) is
just "1 minus kaplan-Meier survival"? Under what circumstance, you should use
cumulative incidence vs KM survival? If the relationship is just CI =
1-survival, then what difference it makes to use one vs. the other?
And in R how I can draw a cumulative incidence plot. I know I can make a
Kaplan-Meier
2008 Aug 22
1
Help on competing risk package cmprsk with time dependent covariate
Dear R users,
I d like to assess the effect of "treatment" covariate on a disease relapse risk with the package cmprsk.
However, the effect of this covariate on survival is time-dependent
(assessed with cox.zph): no significant effect during the first year of follow-up,
then after 1 year a favorable effect is observed on survival (step
function might be the correct way to say that ?).
2008 Dec 09
1
controlling axes in plot.cuminc (cmprsk library)
Dear R-help list members,
I am trying to create my own axes when plotting a cumulative incidence
curve using the plot.cuminc function in the CMPRSK library. The default
x-axis places tick marks and labels at 0, 20, 40, 60, and 80 (my data has
an upper limit of 96), whereas I want them at my own specified locations.
Here is my example code:
library(cmprsk)
attach(MYDATA)
MYCUMINC <-
2009 Mar 29
3
cmprsk- another survival-depedent package causes R crash
Dear Prof Gray and everyone,
As our package developers discussed about incompatibility between Design and survival packages, I faced another problem with cmprsk- a survival dependent packacge.
The problem is exactly similar to what happened to the Design package that when I just started running cuminc function, R was suddenly closed.
These incidents suggest that maybe many other survival
2006 Aug 07
3
Finding points with equal probability between normal distributions
Dear mailing list,
For two normal distributions, e.g:
r1 =rnorm(20,5.2,2.1)
r2 =rnorm(20,4.2,1.1)
plot(density(r2), col="blue")
lines(density(r1), col="red")
Is there a way in R to compute/estimate the point(s) x where the density of the
two distributions cross (ie where x has equal probability of belonging to
either of the two distributions)?
Many Thanks
Eleni
2006 Jul 27
2
memory problems when combining randomForests [Broadcast]
You need to give us more details, like how you call randomForest, versions
of the package and R itself, etc. Also, see if this helps you:
http://finzi.psych.upenn.edu/R/Rhelp02a/archive/32918.html
Andy
From: Eleni Rapsomaniki
>
> Dear all,
>
> I am trying to train a randomForest using all my control data
> (12,000 cases, ~ 20 explanatory variables, 2 classes).
> Because
2012 Jan 09
2
Joint confidence interval for fractional polynomial terms
Dear R users,
The package 'mfp' that fits fractional polynomial terms to predictors.
Example:
data(GBSG)
f <- mfp(Surv(rfst, cens) ~ fp(age, df = 4, select = 0.05)
+ fp(prm, df = 4, select = 0.05), family = cox, data = GBSG)
print(f)
To describe the association between the original predictor, eg. age and
risk for different values of age I can plot it the polynomials
2009 Feb 05
4
See source code for survplot function in Design package
Dear R users,
I know one way to see the code for a hidden function, say function_x,
is using default.function_x (e.g. summary.default). But how can I see
the code for imported packages that have no namespace (in this case
Design)?
Many Thanks
Eleni
2009 Oct 13
2
update.formula drop interaction terms
Dear R users,
How do I drop multiplication terms from a formula using update?
e.g.
forml=as.formula("Surv(time, status) ~ x1+x2+A*x3+A*x4+B*x5+strata(sex)")
#I would like to drop all instances of variable A (the main effect and its interactions). The following:
updated.forml=update(forml, ~ . -A)
#gives me this:
#Surv(time, status) ~ x1 + x2 + x3 + x4 + B + x5 + strata(sex) + A:x3 +
2011 Jun 24
1
UnoC function in survAUC for censoring-adjusted C-index
Hello,
I am having some trouble with the 'censoring-adjusted C-index' by Uno et al, in the package survAUC. The relevant function is UnoC.
The question has to do with what happens when I specify a time point t for the upper limit of the time range under consideration (we want to avoid using the right-end tail of the KM curve).
Copying from the example in the help file:
TR <-
2006 Jul 26
3
memory problems when combining randomForests
Dear all,
I am trying to train a randomForest using all my control data (12,000 cases, ~
20 explanatory variables, 2 classes). Because of memory constraints, I have
split my data into 7 subsets and trained a randomForest for each, hoping that
using combine() afterwards would solve the memory issue. Unfortunately,
combine() still runs out of memory. Is there anything else I can do? (I am not
using
2009 Jun 25
2
crr - computationally singular
Dear R-help,
I'm very sorry to ask 2 questions in a week. I am using the package
'crr' and it does exactly what I need it to when I use the dataset a.
However, when I use dataset b I get the following error message:
Error in drop(.Call("La_dgesv", a, as.matrix(b), tol, PACKAGE = "base")) :
system is computationally singular: reciprocal condition number =
2006 Sep 27
1
Any hot-deck imputation packages?
Hi
I found on google that there is an implementation of hot-deck imputation in
SAS:
http://ideas.repec.org/c/boc/bocode/s366901.html
Is there anything similar in R?
Many Thanks
Eleni Rapsomaniki