Displaying 20 results from an estimated 500 matches similar to: "survexp with weights"
2008 Nov 24
1
Discrepancy in the PBC data set
The data set in R is wrong. I've found mistakes on 2 lines in a quick look.
I don't know if the data is incorrect in the Appendix of Fleming and
Harrington as well (someone seems to have borrowed my copy), which is where the
data set appears to have been taken from, given all the "-9" codes in it. (Note,
Tom Fleming originally got the data from me, so I'm fairly
2006 Sep 03
2
Running cox models
Hi,
I'm reading van Belle et al "Biostatistics" and trying to run a cox test using
a dataset from:
http://faculty.washington.edu/~heagerty/Books/Biostatistics/chapter16.html
(Primary Biliary Cirrhosis data link at top of the page),
I'm using the following code:
--------------- start of code
library(survival)
liver <-
2010 Sep 13
0
using survexp and ratetable with coxph object that includes a factor term
Hello,
I'm attempting to use the ratetable argument to
survexp in the survival package. I use
the example from the ?survexp help page below,
and then slightly modify it to produce an error.
library(survival)
data(pbc)
#fit a model without any factors
pfit1 <- coxph(Surv(time, status > 0) ~ trt + log(bili) +
log(protime) + age + platelet, data=pbc)
#this works as expected
2003 Aug 04
1
coxph and frailty
Hi:
I have a few clarification questions about the elements returned by
the coxph function used in conjuction with a frailty term.
I create the following group variable:
group <- NULL
group[id<50] <- 1
group[id>=50 & id<100] <- 2
group[id>=100 & id<150] <- 3
group[id>=150 & id<200] <- 4
group[id>=200 & id<250] <- 5
group[id>=250
2008 Nov 21
1
Discrepancy in the regression coefficients for Cox regression - PBC data set
Hi,
When I run the following Cox proportional hazards model on the Mayo clinic's
PBC data set (given in the "survival" package), the regression coefficients
do not agree with the results presented in Table 4.6.3 (p. 195) of Fleming &
Harrington's book.
library(survival)
data(pbc)
ans.cox <- coxph(Surv(time, status) ~ log(bili) + log(alb) + age +
log(protime) +
2007 Nov 24
1
Hmisc: can not reproduce figure 4 of Statistical Tables and Plots using S and LATEX
Dear R-users:
I can not reproduce figure 4 of *Statistical Tables and Plots using S and
LATEX* by Prof. Frank Harrell with the following code:
rm(list=ls())
library(Hmisc)
getHdata(pbc)
attach(pbc)
age.groups <- cut2(age, c(45,60))
g <- function(y) apply(y, 2, quantile, c(.25,.5,.75))
y <- with(pbc, cbind(Chol=chol,Bili=bili))
# You can give new column names that are not legal S names
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
2009 Jul 13
0
pbc data
Hi there,
Can anyone please help me because I am going to get crazy with the pbc data set. I just want to apply simple cox regression in the data set. I am a beginner in R but I don't think I am doing anything wrong.
I have the book of Fleming and Harrington 1990. I perform cox regression by typing:
out<- coxph(Surv(times/365,status)~log(bili)+log(proth)+edema+log(albumin)+age)
out
2008 Jan 29
2
Direct adjusted survival?
Hello,
I am trying to find an R function to compute 'direct adjusted survival'
with standard errors. A SAS-macro to do this is presented in Zhang X,
Loberiza FR, Klein JP, Zhang MJ. A SAS macro for estimation of direct
adjusted survival curves based on a stratified Cox regression model.
Comput Methods Programs Biomed 2007;88:95-101. It appears that this
method is not implemented in R.
2004 Oct 15
1
categorical varibles in coxph
Hello,
I wonder when I do coxph in R:
coxph( Surv(start, stop, event) ~ x, data=test)
If x is a categorical varible (1,2,3,4,5), should I creat four dummy
varibles for it? if yes, how can I get the overall p value on x other
than for each dummy variable?
Thanks
Lisa Wang
Princess Margaret Hospital
Phone 416 946 4501
2008 Mar 02
0
new to latex to pdf
Dear All,
I'm trying to teach myself latex along with the latex function in Hmisc
and have hit a roadblock that I can't seem to get around. I'd greatly
appreciate any pointers.
I'm running R 2.6.0 on Windows XP and have Miktex 2.7 installed.
I've reproduced the code below, taken from Frank Harrell's latexsummary
introduction. My question relates to getting a pdf
2007 May 31
0
Using MIcombine for coxph fits
R-helpers:
I am using R 2.5 on Windows XP, packages all up to date. I have run
into an issue with the MIcombine function of the mitools package that I
hoped some of you might be able to help with. I will work through a
reproducible example to demonstrate the issue.
First, make a dataset from the pbc dataset in the survival package
---------------
# Make a dataset
library(survival)
d <-
2008 Feb 15
12
Transfer Crosstable to Word-Document
# Dear list,
# I am an R-beginner and
# spent the last days looking for a method to insert tables produced
# with R into a word document. I thought about SPPS: copy a table from
# an SPO-file and paste it into a word document
# (if needed do some formatting with that table).
# Annother idea was, to produce a TEX-file,
# insert it and make it a word-table.
# I found the following libraries, which
2007 Nov 07
3
Can I replace NA by 0 (if yes, how) ?
Hello,
I'm trying to fit some points with a 8-degrees polynom (result of lm is
stored in pfit).
In most of the case, it is ok but for some others, some coefficients are
"NA".
I don't really understand the meaning of these "NA".
And the problem is that I can't perform a derivation
(pderiv<-as.function((deriv(polynomial(pfit$coefficients))))) on pfit due to
the
2011 Jul 08
4
Using t tests
Dear Sir,
I am doing some work on a population of patients. About half of them are
admitted into hospital with albumin levels less than 33. The other half have
albumin levels greater than 33, so I stratify them into 2 groups, x and y
respectively.
I suspect that the average length of stay in hospital for the group of
patients (x) with albumin levels less than 33 is greater than those
2010 Dec 31
3
survexp - example produces error
Dear All,
reposting, because I did not find a solution, maybe someone could
check the example below.
It's taken from the help page of survdiff. Executing it, gives the error
"Error in floor(temp) : Non-numeric argument to mathematical function"
best regards,
Heinz
library(survival)
## Example from help page of survdiff
## Expected survival for heart transplant patients based
2005 Dec 15
2
survexp ratetables for european contries?
Dear All,
Does someone have, or know of survexp ratetables for european contries,
especially Austria and Germany?
I know only about slopop in the package relsurv.
Thanks in advance
Heinz T??chler
2000 Apr 05
1
problem with survexp in survival5
survexp in survival5 doesn't seem to work for me. see below:
> library(survival5)
Attaching Package "package:survival5":
The following object(s) are masked from package:base :
sort.list
> library(chron)
> data(ratetables)
> survexp(~ratetable(year=julian(6,1,1991),
+ sex=1,age=35*365.24),times=(0:30)/6*365.24)
Error in as.character(as.date(c(min(R[, 3]),
2007 Nov 06
1
How to find the zero (only the real solution) with the package polynom ?
Hello,
I have 3 columns : a, b and a*b
I would like to find the pair (a,b) so that a*b is the minimum but not from
the points I measured but from the fit of the curve (I have more points that
the ones given below but I fit only on this part because I
know that the minimum a*b is in this interval).
I thought doing it this way :
- to fit a*b=f(a)
abfit<-lm(ab ~ poly(a,8,raw=T))
- to use the
2004 Apr 09
2
Regression models w/ splines
Hi - I am fitting various Cox PH models with spline predictors. After
fitting the model, I would like to use termplot() to examine the
functional form of the fitted model (e.g., to obtain a plot of the
relative risk (or log r.r.) versus the predictors).
When there is only 1 predictor in the model, termplot returns a "?".
In this case, I have not been able to figure out how to create