Displaying 20 results from an estimated 2000 matches similar to: "Confidence interval of Survival Curve of Weighted Cox Regression"
2010 Apr 27
1
Problem with time in coxph/survfit
Hi!
I am having a few problems with coxph function, I had the same problem with
the use of survfit. Here it is:
when calling 'M22<-coxphw(Surv(V1,V2,V4)~V5, data=XTDV, id=XTDV$V3, *
prentice*= ~V5, robust=TRUE, censcorr=TRUE)'
knowning that my data is:
> XTDV[1:10,1:3]
V1 V2 V3 V4 V5
1 0 36.39706 36 1 343.2224
2 0 36.39706 943 0 161.5931
3 0 36.39706
2006 Feb 20
1
Grandstream BT-101 POS Error
Hi-
I'm at my wit's end trying to get a Grandstream BT-101 POS to
register on my * server. Asterisk version is 1.2.1. GS Firmware is rev
1.0.6.7.
Basically, I've setup the phone following the instructions at
voip-info.org, and it registers for about 10 seconds, then after
receiving the SIP NOTIFY from the * server, goes into "flashing display"
mode, which indicates some
2005 Jun 29
0
predicted survival curve from a cox model
Hi there,
I have a predictor varible "class" which is a categorical variable and
a ' coxph' is used to find the coeffients. How can I plot the predicted
survival proportion based on this model?
Thanks
Lisa Wang
Princess Margaret Hospital
Toronto
tel 416 946 4501
2006 Apr 07
1
fuzzy classification and dissimilarity matrix
Hello,
I want to make a fuzzy classification from a dissimilarity matrix
(calculated with daisy from package 'cluster'). I have tried to use
fanny (package cluster) but I have the same problems than described in a
previous message
(http://tolstoy.newcastle.edu.au/R/help/05/05/4546.html) i.e. it always
gives me two clusters in the results (even if k is different from 2)
with the same
2002 Jun 24
3
Weird problem - one machine works another doesn't on new server - both OK on old one.
Hello and Thanks in Advance,
I've been at this for three days now and can't think of anything else to
try. Been through the docs and #samba on openprojects and even begged
for direction in #samba-technical who suggested writing here.
On the ancient RedHat 5.2 server (SAMBA 1.9?) both boxes work OK and
continue to work OK with both servers now up (new one is from Mandrake
8.2 - SAMBA
2006 Mar 20
1
type in daisy
Hi,
I'm a PhD student and I want to use the function 'daisy' from the
package 'cluster' to compute dissimilarities.
My variables are of mixed types so I use the argument 'stand' in daisy
to define the type of my variables.
I have the following error message :
Warning message:
binary variable(s) 13, 16, 17, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35,
2006 May 05
1
MRPP in R
Hello,
I'm looking for a R function proceeding MRPP (Multi-Response Permutation
Procedures). Is it available?
Thanking you in anticipation,
Jeanne Vallet, PhD student
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2007 May 04
0
Predicted Cox survival curves - factor coding problems...
I am trying to use the survfit() function with the newdata argument to
produce predicted survivor curves for a particular covariate profile.
The main purpose of the plot will be to visualise the effect of snp1,
coded 0 and 1. In my Cox model I have stratified by one variable, edu, and
so I know I will automatically get a separate curve for each strata. My
problem is how to deal with the
2006 Aug 02
0
expected survival from a frailty cox model using survfit
Hello R users
Would somebody know how to estimate survival from a frailty cox model,
using the function survfit
and the argument newdata ? (or from any other way that could provide
individual expected survival
with standard error); Is the problem related to how the random term is
included in newdata ?
kfitm1 <- coxph(Surv(time,status) ~ age + sex + disease + frailty(id,
2007 May 07
1
Predicted Cox survival curves - factor coding problems..
The combination of survfit, coxph, and factors is getting confused. It is
not smart enough to match a new data frame that contains a numeric for sitenew
to a fit that contained that variable as a factor. (Perhaps it should be smart
enough to at least die gracefully -- but it's not).
The simple solution is to not use factors.
site1 <- 1*(coxsnps$sitenew==1)
site2 <-
2011 Jul 15
1
Plotting survival curves from a Cox model with time dependent covariates
Dear all,
Let's assume I have a clinical trial with two treatments and a time to
event outcome. I am trying to fit a Cox model with a time dependent
treatment effect and then plot the predicted survival curve for one
treatment (or both).
library(survival)
test <-
list(time=runif(100,0,10),event=sample(0:1,100,replace=T),trmt=sample(0:1,100,replace=T))
model1 <- coxph(Surv(time,
2006 Aug 09
0
Weighted Mean Confidence Interval
Hello,
I'm looking to calculate a 95% confidence interval about my estimate for
a sample's weighted mean, where the calculated confidence interval would
equal the t-test confidence interval of the sample in the case when all
of the weights are equal.
My initial thought was to simply implement a modified version of the
t-test function but substituting the weighted variance and mean for the
2007 Jan 25
0
cox.zph vs log-log survival plot
Hello,
Excuse me for a more methodological than technical question. I'm developing a Cox model with 10 covariates. One of them is age (named "eta"). I've checked proportionality with cox.zph with age continuous:
> cox.zph(coxph(Surv(TTP,CENSOTTP)~eta))
rho chisq p
eta -0.0154 0.0225 0.88
and categorical (eta<60):
>
2012 Jan 17
1
Scoring using cox model: probability of survival before time t
Dear Members,
I required to score probability of survival before specified time using
fitted cox model on scoring dataset.
On the training sample data I am able to get the probability of a survival
before time point(t), but on the scoring dataset, which will have only
predictor information I am facing some issues. It would be great help for me
if you tell me where am I going wrong!
Here is the
2011 Nov 20
1
Cox proportional hazards confidence intervals
I am calculating cox propotional hazards models with the coxph
function from the survival package. My data relates to failure of
various types of endovascular interventions. I can successfully
obtain the LR, Wald, and Score test p-values from the coxph.object, as
well as the hazard ratio as follows:
formula.obj = Surv(days, status) ~ type
coxph.model = coxph(formula.obj, df)
fit =
2011 Jul 01
3
Multilevel Survival Analysis - Cox PH Model
Hello all, thanks for your time and patience.
I'm looking for a method in R to analyse the following data:
Time to waking after anaesthetic for medical procedures repeated on the same
individual.
> str(mysurv)
labelled [1:740, 1:2] 20 20 15 20 30+ 40+ 50 30 15 10 ...
- attr(*, "dimnames")=List of 2
..$ : NULL
..$ : chr [1:2] "time" "status"
-
2013 Feb 07
2
how to draw confidence interval lines of a fitted curve of polynominal regression
Hello,
I drew a plot of weight and height of people and fitted it with a
polynominal regression x^2.
(using curve())
Now I would like to draw the confidence interval line for the fitted curve.
Please kindly advise the code for the purpose.
Thank you.
Elaine
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2010 Aug 17
1
confidence intervals for Harrell's c-index in survival setting
Dear All,
Is it possible to get confidence intervals for Harrell's concordance index or, equivalently, Somer's D using the rms package or in some other way ?
I have survival data it would be the c-index in the Cox model setting
Many thanks
Dr Bernard North
Statistical Consultant
Statistical Advisory Service
Advice and Courses on Research Design and Methodology
Imperial College South
2013 Jun 05
0
[R-pkgs] bpcp package for pointwise confidence intervals for a survival distribution
Hi all,
I just uploaded a new version of the bpcp package. It calculates confidence intervals for a survival distribution for right-censored data using the newly developed beta product confidence procedure. Previously developed methods can have substantial error rate inflation for the lower limit, especially at the right end of the curves when there are small numbers of events. The bpcp method
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