Displaying 19 results from an estimated 19 matches similar to: "Running cox models"
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
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
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
2010 Mar 15
3
the problem about sample size
Hi all:
I am a user of "JM" package.
Here's the problem of "sample size".
The warning is:
Error in jointModel(fitLME, fitSURV_death, timeVar = "time", method = "piecewise-PH-GH") :
sample sizes in the longitudinal and event processes differ.
According to the suggestion of "missing data",I use the same data set(data_JM) without any
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 07
1
Aggregate with non-scalar function
R-Helpers,
I'm sorry to have to ask this -- I've not used R very much in the last
8 or 10 months, and I've gotten rusty.
I have the following (ff2 is a subset of a much, much larger dataset):
> ff2
hostName user sys idle obsTime
10142 fred 0.4 0.5 98.0 2007-11-01 02:02:18
16886 barney 0.5 0.2 94.6 2007-10-25 19:12:12
8795 fred 0.0 0.1 99.8
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
2006 Aug 30
1
lmer applied to a wellknown (?) example
Dear all,
During my pre-R era I tried (yes, tried) to understand mixed models by
working through the 'rat example' in Sokal and Rohlfs Biometry (2000)
3ed p 288-292. The same example was later used by Crawley (2002) in his
Statistical Computing p 363-373 and I have seen the same data being used
elsewhere in the litterature.
Because this example is so thoroughly described, I thought
2003 Mar 12
1
simulating 'non-standard' survival data
Dear all,
I'm looking for someone that help me to write an R function to simulate
survival data under complex situations, namely time-varying hazard ratio,
marginal distribution of survival times and covariates. The algorithm is
described in the reference below and it should be not very difficult to
implement it. However I tried but without success....;-(
Below there the code that I used; it
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
2012 Jan 19
2
Reading in tab (and space) delimited data within a script XXXX
Hello everyone,
I use Bob Muenchen's approach for reading in "in-stream" (to use SAS
parlance) delimited data within a script. This works great:
mystring <-
"id,workshop,gender,q1,q2,q3,q4
1,1,f,1,1,5,1
2,2,f,2,1,4,1
3,1,f,2,2,4,3
4,2, ,3,1, ,3
5,1,m,4,5,2,4
6,2,m,5,4,5,5
7,1,m,5,3,4,4
8,2,m,4,5,5,5"
mydata <- read.table( textConnection(mystring),
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
2004 Dec 08
2
NEC Univerge
hi * users,
anyone out there ever come across, worked with or heard anything about
NEC's Univerge SV7000 Telephony Server? Link is at
http://www.univerge.nec.com/products/list/sv7000/sv7000.html
I'm just wondering whether it's as flexible, programmable and
configurable as Asterisk.
It also looks like they've got a whole range of IP phones
2008 Aug 22
0
Censored Poisson Data
Dear list,
I am wondering whether R allows to perform a Poisson regression on
counting data which include censored observations, that is, observations of the form
"2 events or more" or "less than 2 events" or even "1 or 2 events".
Can anyone give me a hint whether this is already possible and how to do it?
Data of the form (obstime is the observation time,
2006 Aug 08
1
Fitting data with optim or nls--different time scales
Hi,
I have a system of ODE's I can solve with lsoda.
Model=function(t,x,parms)
{
#parameter definitions
lambda=parms[1]; beta=parms[2];
d = parms[3]; delta = parms[4];
p=parms[5]; c=parms[6]
xdot[1] = lambda - (d*x[1])- (beta*x[3]*x[1])
xdot[2] = (beta*x[3]*x[1]) - (delta*x[2])
xdot[3] = (p*x[2]) - (c*x[3])
return(list(xdot))
}
I want
2008 Jul 01
1
Help on Analysis of covariance
Dear All,
Kindly tell me the steps to perform analysis of covariance (ANCOVA). Can I find anything in the help(). My prime objective is to analyze the genotypic and phenotypic correlation coefficients.
Thanks,
Partha
Partha Protim Banerjee, Ph. D.
Scientist - Corn Breeding
Hytech Seed India Pvt. Ltd.
ICRISAT, Bldg: 303, Room: 15-23
Patancheru, Hyderabad
India
p.banerjee@hytechseed.in
+91
2011 May 23
0
Basic questions about share permissions
I'm implementing a Samba 3.5.4 server, and have some basic questions
about controlling share-level permissions. To let you know my level of
knowledge, I'm a pretty good Linux admin, and can do basic Windows
domain admin work.
My goal is fairly simple: I need several shares that will be used by
Windows users to send and get files from a Unix process. One share
would do it, except that I
2008 Oct 30
2
p-value=0 running coxph
Dear all,
I have a question concerning the p-value. When running coxph I get a p-value
= 0. :confused:
Can this be true? Why aren?t there decimal points? Is there a way to find
out the exact p-value?
Here is the output:
----------------------------------------------------------------------------------------------------
Call:
coxph(formula = Surv(start, stop, status) ~ Albumin_gproL, data = dial,
2015 Jun 19
2
Sobre data.table
Mª Luz,
si el comando de Carlos te devuelve 0 es que no hay NA's.
Da igual que tus columnas sean caracteres o número.
Lo que intuyo es que tienes celdas con la frase "NA" que interpretas como NA.
Mandanos el summary de tu data.table y lo vemos...
----- Mensaje original -----
De: "MªLuz Morales" <mlzmrls en gmail.com>
Para: "Carlos J. Gil Bellosta"