Displaying 20 results from an estimated 200 matches similar to: "Discrepancy in the PBC data set"
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) +
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
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 <-
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
2011 Apr 20
2
survexp with weights
Hello,
I probably have a syntax error in trying to generate an expected
survival curve from a weighted cox model, but I can't see it. I used
the help sample code to generate a weighted model, with the addition
of a "weights=albumin" argument (I only chose albumin because it had
no missing values, not because of any real relevance). Below are my
code with the resulting error
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
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 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
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 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
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
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.
2024 Jun 15
1
Hard crash of lme4 in R-devel
I ran across this by accident when working up an example. It uses a data set from the survival package, but nothing else from there. Fails on the Intel machine shown below, and on a virtual linux instance on a newer Mac.
Terry
> library(survival)
> library(lme4)
Loading required package: Matrix
> sessionInfo()
R Under development (unstable) (2024-06-14 r86747)
Platform:
2010 Dec 13
1
Multivariate binary response analysis
Greetings ~
I need some assistance determining an appropriate approach to analyzing multivariate binary response data, and how to do it in R.
The setting: Data from an assay, wherein 6-hours-post-fertilization zebrafish embryos (n=20, say) are exposed in a vial to a chemical (replicated 3 times, say), and 5 days later observed for the presence/absence (1/0) of defects in several organ systems
2013 Nov 14
1
issues with calling predict.coxph.penal (survival) inside a function
Thanks for the reproducable example. I can confirm that it fails on my machine using
survival 2-37.5, the next soon-to-be-released version,
The issue is with NextMethod, and my assumption that the called routine inherited
everything from the parent, including the environment chain. A simple test this AM showed
me that the assumption is false. It might have been true for Splus. Working this
2008 Apr 14
2
Bug in ci.plot(HH Package) (PR#11163)
Full_Name: Yasuhiro Nakajima
Version: 2.6.1
OS: WinXP SP2
Submission from: (NULL) (202.237.255.13)
Dear all,
I noticed the following behaviour of ci.plot in HH Package(ver.2.1-9):
> library(HH)
> data(women, package="datasets")
> attach(women)
> ft <- lm(height~weight)
> windows()
> ci.plot(ft,conf.level=0.95)
> windows()
> ci.plot(ft,conf.level=0.999)
I
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 02
1
thunderbird crashed-mail_max_userip
thunderbird just crashed, and I've never seen this before. Any idea what
happened?
this was in the dovecot log:
2010-12-02 13:06:40 imap-login: Info: Maximum number of connections from
user+IP exceeded (mail_max_userip_connections): user=<pbc>,
method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured
2010-12-02 13:06:40 imap-login: Info: Maximum number of connections from
user+IP exceeded
2005 Jul 21
1
About object of class mle returned by user defined functions
Hi,
There is something I don't get with object of class "mle" returned by a
function I wrote. More precisely it's about the behaviour of method
"confint" and "profile" applied to these object.
I've written a short function (see below) whose arguments are:
1) A univariate sample (arising from a gamma, log-normal or whatever).
2) A character string
2010 Jul 17
0
Adjustment for multiple-comparison for log-rank test
DeaR experts,
I was asked for a log-rank pairwise survival comparison. I've a straightforward way
to do this using the SAS system:
http://support.sas.com/documentation/cdl/en/statug/63033/HTML/default/viewer.htm#/documentation/cdl/en/statug/63033/HTML/default/statug_lifetest_sect019.htm
What I've found in R is shown below, but it's not a logrank test,
I suppose. (The documentation