similar to: fraitly in coxph

Displaying 20 results from an estimated 10000 matches similar to: "fraitly in coxph"

2007 Apr 20
1
Approaches of Frailty estimation: coxme vs coxph(...frailty(id, dist='gauss'))
Dear List, In documents (Therneau, 2003 : On mixed-effect cox models, ...), as far as I came to know, coxme penalize the partial likelihood (Ripatti, Palmgren, 2000) where as frailtyPenal (in frailtypack package) uses the penalized the full likelihood approach (Rondeau et al, 2003). How, then, coxme and coxph(...frailty(id, dist='gauss')) differs? Just the coding algorithm, or in
2007 Oct 09
0
coxph models for insects
Justin, You have an interesting problem, and a serious (reliable) consultation would take more time than I have to give at the moment. Which is to say that you should take these comments with a grain of salt. First, I don't think that you have censored data. You have 2 subdistribution functions F1(t) and F2(t), F1(t) + F2(t) = F(t) = the "time to endpoint" distribution.
2009 Jan 07
0
Frailty by strata interactions in coxph (or coxme)?
Hello, I was hoping that someone could answer a few questions for me (the background is given below): 1) Can the coxph accept an interaction between a covariate and a frailty term 2) If so, is it possible to a) test the model in which the covariate and the frailty appear as main terms using the penalized likelihood (for gaussian/t frailties) b)augment model 1) by stratifying on the variable that
2012 Feb 03
1
coxme with frailty--variance of random effect?
Dear all, This probably stems from my lack of understanding of the model, but I do not understand the variance of the random effect reported in coxme. Consider the following toy example: #------------------------------- BEGINNING OF CODE ------------------------------------------------ library(survival) library(coxme) #--- Generate toy data: d <- data.frame(id = c(1:100), #
2011 Dec 30
0
New version of coxme / lmekin
Version 2.2 of coxme has been posted to CRAN, Windows versions and mirrors should appear in due course. This is a major update with three features of note: 1. A non-upwardly compatable change: Extractor functions: beta= fixed effects, b=random effects nlme lme4 coxme <2.2 coxme 2.2 lmekin 2.2 ------------------------------------------------------ beta
2013 Nov 04
0
Fwd: Re: How to obtain nonparametric baseline hazard estimates in the gamma frailty model?
-------- Original Message -------- Subject: Re: How to obtain nonparametric baseline hazard estimates in the gamma frailty model? Date: Mon, 04 Nov 2013 17:27:04 -0600 From: Terry Therneau <therneau.terry at mayo.edu> To: Y <yuhanusa at gmail.com> The cumulative hazard is just -log(sfit$surv). The hazard is essentially a density estimate, and that is much harder. You'll notice
2011 Jun 25
2
cluster() or frailty() in coxph
Dear List, Can anyone please explain the difference between cluster() and frailty() in a coxph? I am a bit puzzled about it. Would appreciate any useful reference or direction. cheers, Ehsan > marginal.model <- coxph(Surv(time, status) ~ rx + cluster(litter), rats) > frailty.model <- coxph(Surv(time, status) ~ rx + frailty(litter), rats) > marginal.model Call: coxph(formula =
2003 Aug 04
1
coxph and frailty
Hi: I have a few clarification questions about the elements returned by the coxph function used in conjuction with a frailty term. I create the following group variable: group <- NULL group[id<50] <- 1 group[id>=50 & id<100] <- 2 group[id>=100 & id<150] <- 3 group[id>=150 & id<200] <- 4 group[id>=200 & id<250] <- 5 group[id>=250
2010 Apr 23
2
Deferred Default Marker
I've finally narrowed down a puzzling problem: here is the short test case. tmt34% R --vanilla R version 2.10.0 (2009-10-26) Copyright (C) 2009 The R Foundation for Statistical Computing ISBN 3-900051-07-0 > temp <- matrix(runif(50), ncol=2) > t(temp) %*% temp [,1] [,2] [1,] 7.916016 6.049698 [2,] 6.049698 7.650694 > library(kinship) Loading required package:
2006 Sep 21
0
frailty in coxph
Dear all, I have been doing some frailty calculations and been facing some difficulties. I can extract coefficients, value of theta and the following things library(survival) fit<-coxph(Surv(time,status)~covariate+frailty(group), data=simulated.data) fit$coef fit$history[[1]]$theta fit$history[[1]]$c.loglik fit$var fit$var2 from a frailty included coxph object: but how can i know what other
2012 Dec 03
1
fitting a gamma frailty model (coxph)
Dear all, I have a data set<http://yaap.it/paste/c11b9fdcfd68d02b#gIVtLrrme3MaiQd9hHy1zcTjRq7VsVQ8eAZ2fol1lUc=>with 6 clusters, each containing 48 (possibly censored, in which case "event = 0") survival times. The "x" column contains a binary explanatory variable. I try to describe that data with a gamma frailty model as follows: library(survival) mod <-
2018 Mar 28
0
coxme in R underestimates variance of random effect, when random effect is on observation level
Hello, I have a question concerning fitting a cox model with a random intercept, also known as a frailty model. I am using both the coxme package, and the frailty statement in coxph. Often 'shared' frailty models are implemented in practice, to group people who are from a cluster to account for homogeneity in outcomes for people from the same cluster. I am more interested in the classic
2013 Jun 04
0
Mixed effects model with a phylogenetic tree/ distance, matrix as a random effect
Take a look at lmekin() in the coxme package. The motivating data set for my development of coxme was the Minnesota Family Breast Cancer project: 24050 subjects in 462 families. The random effect is an intercept per subject with sigma^2 K as its variance where K is the kinship matrix (1 for self-self, .5 for parent-child or sib-sib, .25 for uncle-neice, etc). lmekin is a linear models front
2005 Oct 06
1
Testing strata by covariate interactions in coxph
Dear list members, I am working with a Cox ph model for the duration of unemployment. The event of interest in my analysis is getting employed. I have various background variables explaining this event: age, sex, education etc. I have multiple unemployment spells per person. I use a model with person-specific frailty terms in order to take into account the correlation of spells by the same
2009 Aug 05
1
inheriting C symbols
The package coxme depends heavily on bdsmatrix, to the point of needing access to some of its C calls. The kinship package (in progress) uses the R level functions in bdsmatrix, but not the C calls. That is, I don't want to always export the symbols. For testing I can use an explicit dyn.load('somepath/bsdmatrix.so', local=F). How do I incorporate such a dependency in the
2007 Dec 05
4
coxme frailty model standard errors?
Hello, I am running R 2.6.1 on windows xp I am trying to fit a cox proportional hazard model with a shared Gaussian frailty term using coxme My model is specified as: nofit1<-coxme(Surv(Age,cen1new)~ Sex+bo2+bo3,random=~1|isl,data=mydat) With x1-x3 being dummy variables, and isl being the community level variable with 4 levels. Does anyone know if there is a way to get the standard error
2011 Dec 30
2
Joint modelling of survival data
Assume that we collect below data : - subjects = 20 males + 20 females, every single individual is independence, and difference events = 1, 2, 3... n covariates = 4 blood types A, B, AB, O http://r.789695.n4.nabble.com/file/n4245397/CodeCogsEqn.jpeg ?m = hazards rates for male ?n = hazards rates for female Wm = Wn x ?, frailty for males, where ? is the edge ratio of male compare to female Wn =
2009 Nov 13
2
error checks
I'm currently packaging up some of the kinship matrix routines more formally, these are used in coxme when dealing with family correlation structures. One of my test programs exercises error conditions, i.e., it purposely feeds particular types of invalid pedigree data in to see if the right error message results. So there are comment-action pairs # the next line should generate a
2010 Apr 06
0
Strange error
Someone just sent me a data set that causes the lmekin function, part of the kinship package, to fail. In chasing it down I get an error I have never seen before. fit <- lmekin(icam1 ~ factor(center) + age + factor(sex), random= ~1|iid, data=chaidata, varlist=kmat) Error in Y - fitted : non-numeric argument to binary operator Add the recover option, and the offending lines are
2006 Mar 30
1
Random Coefficients using coxme
Hello, I was hoping someone could answer a question for me that may either be statistical or script related. I don't come from a statistics background, so I am not positive if I am using the correct nomenclature or even the correct procedure. Is it possible to model "random coefficients" in a mixed effects cox-regression using coxme from the Kinship package? For example, using