Re: [R] AFT model time-dependent with weibull distribution

2012-08-04 Thread hafida
thanks a lot sorry for the mistake that i do in exponential, i am "francophone" and for the programme if we want to apply the "power rule " condition we use log(vi). it works thank yo -- View this message in context: http://r.789695.n4.nabble.com/AFT-model-time-dependent-with-weibull-di

Re: [R] AFT model time-dependent with weibull distribution

2012-08-04 Thread Rui Barradas
Hello, Vous êtes française? It shows, in english it would be 'exponential', with an 'a'. Worked with me, after reading the manual. dataexp <- read.table(text=" vi Ti 1 265.79 2 26 1579.52 3 26 2323.70 4 28 68.85 [...] 73 380.39 74 381.13 75 380.09 76 382.38 ", he

Re: [R] AFT model time-dependent with weibull distribution

2012-08-04 Thread David Winsemius
On Aug 4, 2012, at 10:45 AM, hafida wrote: Dear R-community, I have tried to estimate an EXPONENTIEL accelerated failure time(AFT) power rule model with time-independent . For that purpose, I have used the eha package. Please, consider this example: vi Ti 1 265.79 2 26 1579.

Re: [R] AFT model time-dependent with weibull distribution

2012-08-04 Thread hafida
Dear R-community, > > I have tried to estimate an EXPONENTIEL accelerated failure time(AFT) > power rule model with time-independent . For that purpose, I have used > the eha package. > Please, consider this example: vi Ti 1 265.79 2 26 1579.52 3 26 2323.70 4 28 68.85 5 28

Re: [R] AFT model time-dependent with weibull distribution

2011-08-21 Thread JPF
thanks! -- View this message in context: http://r.789695.n4.nabble.com/AFT-model-time-dependent-with-weibull-distribution-tp3755079p3758267.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat

Re: [R] AFT model time-dependent with weibull distribution

2011-08-21 Thread Göran Broström
On Sat, Aug 20, 2011 at 7:33 PM, JPF wrote: > > Göran Broström wrote: >> >> >> Good. Do you still need answers to your other questions? >> >> > > Yes. Could answer the following two questions: > > 1- Can I use phreg function to estimate  a model with time-dependent > covariates? In case of a posit

Re: [R] AFT model time-dependent with weibull distribution

2011-08-20 Thread JPF
question 2 *aftreg vs. survreg* for aftreg = S0 *{t/exp(b-BXi)]^a} a= shape and b= log(scale) for survreg and stata S0 *{t*exp(intercept+BXi)]^1/p} p=shape /intercept, log(scale) and estimates are equivalent with reversed sign./ *PH and AFT* /phreg.Bhat= aftreg.Bhat * shape /

Re: [R] AFT model time-dependent with weibull distribution

2011-08-20 Thread JPF
Göran Broström wrote: > > > Good. Do you still need answers to your other questions? > > Yes. Could answer the following two questions: 1- Can I use phreg function to estimate a model with time-dependent covariates? In case of a positive answer, how? 2- I could not find any example that

Re: [R] AFT model time-dependent with weibull distribution

2011-08-20 Thread Göran Broström
On Sat, Aug 20, 2011 at 4:19 AM, JPF wrote: > > JPF wrote: >> >> >> >> weibullaft<-aftreg(Surv(sta,time,S) ~ TDC1 + TIC1, dist="weibull", >> data.frame=Data) >> >> ## aftreg gives an error when I add an ID argument... That should be used >> for controlling for time-varying variables. >> >> Error i

Re: [R] AFT model time-dependent with weibull distribution

2011-08-19 Thread JPF
JPF wrote: > > > > weibullaft<-aftreg(Surv(sta,time,S) ~ TDC1 + TIC1, dist="weibull", > data.frame=Data) > > ## aftreg gives an error when I add an ID argument... That should be used > for controlling for time-varying variables. > > Error in aftreg.fit(X, Y, dist, strats, offset, init, shape

Re: [R] AFT model time-dependent with weibull distribution

2011-08-19 Thread JPF
Dear Prof. Broström, I have searched in the reference manual inside the package eha, updated recently. I did not find any description on how to enter id in the aftreg function except the description of the argument. Can you refer to a specific part of the manual? Do you mean another documentatio

Re: [R] AFT model time-dependent with weibull distribution

2011-08-19 Thread Göran Broström
On Fri, Aug 19, 2011 at 2:55 PM, javier palacios wrote: > Dear R-community, > > I have tried to estimate an accelerated failure time(AFT) and proportional > hazard (PH) parametric survival model with time-independent  and > time-dependent covariates. For that purpose, I have used the eha package.

[R] AFT model time-dependent with weibull distribution

2011-08-19 Thread javier palacios
Dear R-community, I have tried to estimate an accelerated failure time(AFT) and proportional hazard (PH) parametric survival model with time-independent and time-dependent covariates. For that purpose, I have used the eha package. Please, consider this example: weibullph <- phreg(Surv(sta,ti

Re: [R] AFT-model with time-varying covariates and left-truncation

2010-02-01 Thread Philipp Rappold
Thanks for your super-fast reply. I realized you're totally right: My problem is not left truncation but missing data of time-varying covariates. In my special case, two conditions are given by study design: (1) A lot of subjects are missing all of their (time-varying) covariates for a certai

Re: [R] AFT-model with time-varying covariates and left-truncation

2010-01-29 Thread Göran Broström
On Thu, Jan 28, 2010 at 2:32 PM, Philipp Rappold wrote: > Dear Prof. Broström, > Dear R-mailinglist, > > first of all thanks a lot for your great effort to incorporate time-varying > covariates into aftreg. It works like a charm so far and I'll update you > with detailled benchmarks as soon as I h

[R] AFT-model with time-varying covariates and left-truncation

2010-01-28 Thread Philipp Rappold
Dear Prof. Broström, Dear R-mailinglist, first of all thanks a lot for your great effort to incorporate time-varying covariates into aftreg. It works like a charm so far and I'll update you with detailled benchmarks as soon as I have them. I have one more questions regarding Accelerated Failu

Re: [R] AFT-model with time-dependent covariates

2009-10-20 Thread Ravi Varadhan
n...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Göran Broström Sent: Tuesday, October 20, 2009 10:07 AM To: spencerg Cc: r-help@r-project.org; Terry Therneau Subject: Re: [R] AFT-model with time-dependent covariates Sorry for being late in responding to this thread, but I

Re: [R] AFT-model with time-dependent covariates

2009-10-20 Thread Göran Broström
Sorry for being late in responding to this thread, but I was made aware of it only two weeks ago. In my package 'eha' there is a function 'aftreg', which performs what is asked for, given that the time-varying covariates are step functions of time and that the observation period for each individual

Re: [R] AFT-model with time-dependent covariates

2009-05-13 Thread spencerg
To see what's available in other packages, try the following: library(RSiteSearch) AFT <- RSiteSearch.function('AFT model') summary(AFT) # 24 help files found in 8 different packages HTML(AFT) # opens a table with 24 rows in a web browser. There may be nothing here that will help you,

Re: [R] AFT-model with time-dependent covariates

2009-05-13 Thread Terry Therneau
The coding for an AFT model with time-dependent covariates will be very hard, and I don't know of anyone who has done it. (But I don't keep watch of other survival packages, so something might be there). In a Cox model, a subject's risk depends only on the current value of his/her covariat

[R] AFT-model with time-dependent covariates

2009-05-12 Thread Philipp Rappold
Dear R-community, Dear Prof. Therneau, I would like to fit an AFT-model with time-dependent covariates and right-censored data. Searching the mailing list for information on the subject, I found some old posts which said it didn't work back then. My questions: (1) Has this kind of fitting al

Re: [R] AFT model

2009-03-18 Thread tsn4867
Thank you, Dr. Lumley. I have implemented the following code for the pareto distribution (see below). However, the estimates obtained from survreg are very small & inaccurate. What I need help with is the function for the deviance (the code below is wrong). I just don't understand how to ob

Re: [R] AFT model

2009-03-18 Thread Thomas Lumley
On Tue, 17 Mar 2009, tsn4867 wrote: Hi, In the package survival, using the function survreg for AFT model, I only see 4 distributions for the response y: weibull, gaussian, logistic, lognormal and log-logistic, which correspond to certain distributions for the error terms. I'm wondering i

[R] AFT model

2009-03-17 Thread tsn4867
Hi, In the package survival, using the function survreg for AFT model, I only see 4 distributions for the response y: weibull, gaussian, logistic, lognormal and log-logistic, which correspond to certain distributions for the error terms. I'm wondering if there is a package or how to obta