Displaying 20 results from an estimated 2000 matches similar to: "AFT model"
2010 Nov 25
2
aftreg vs survreg loglogistic aft model (different intercept term)
Hi, I'm estimating a loglogistic aft (accelerated failure time) model, just a
simple plain vanilla one (without time dependent covariates), I'm comparing
the results that I obtain between aftreg (eha package) and survreg(surv
package). If I don't use any covariate the results are identical , if I add
covariates all the coefficients are the same until a precision of 10^4 or
10^-5 except
2009 May 12
1
AFT-model with time-dependent covariates
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 already been implemented in the survival library in R?
(2) If not: Are there any alternatives/
2010 Jan 28
1
AFT-model with time-varying covariates and left-truncation
Dear Prof. Brostr?m,
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 Failure Time models
(with aftreg):
You mention that left truncation in combination with time-varying
2012 Apr 22
1
Survreg
Hi all,
I am trying to run Weibull PH model in R.
Assume in the data set I have x1 a continuous variable and x2 a
categorical variable with two classes (0= sick and 1= healthy). I fit the
model in the following way.
Test=survreg(Surv(time,cens)~ x1+x2,dist="weibull")
My questions are
1. Is it Weibull PH model or Weibull AFT model?
Call:
survreg(formula = Surv(time, delta) ~ x1
2009 Feb 24
2
Configuring chan_dahdi.conf for Sangoma A200/Remora FXO/FXS Analog AFT card
Hi I have been having a rough time getting a Sangoma A200/Remora FXO/
FXS Analog AFT card set up properly.
The main issue is that the card has four ports and as far as I can
tell Asterisk is only seeing two. On the two that it recognizes the
"Green" FXS ports are not green, they just are not lit. The "RED" FXO
ports are indeed red, but from what I have read your not
2011 Dec 07
1
survreg() provides same results with different distirbutions for left censored data
Hello,
I'm working with some left censored survival data using accelerated failure
time models. I am interested in fitting different distributions to the data
but seem to be getting the same results from the model fit using survreg
regardless of the assumed distribution.
These two codes seem to provide the same results:
aft.gaussian <-
2005 Aug 27
1
survival parametric question
Hi to all,
I am working on design package using survival function.
First using PSM and adopting a weibull specification for the baseline hazard , I have got the following results(since weibull has both PH and AFT propreties ,in addition I have used the PPHSm command):
Value Std. Error z p
(Intercept) 1.768 1.0007 1.77 7.73e-02
SIZE -0.707 0.0895 -7.90 2.80e-15
2011 Dec 30
1
Calculate survival function for AFT model
I have fit an accelerated failure time model using coxph, and have what seems
to be a simple question that I can't figure out.
Given a vector of predictor values X, the survival time S[t|X] is the
probability the entity will survive longer than some time t. Now, how do I
calculate this for a specific value of t?
--
View this message in context:
2011 Jan 28
1
survreg 3-way interaction
> I was wondering why survreg (in survival package) can not handle
> three-way interactions. I have an AFT .....
You have given us no data to diagnose your problem. What do you mean
by "cannot handle" -- does the package print a message "no 3 way
interactions", gives wrong answers, your laptop catches on fire when you
run it, ....?
Also, make sure you read
2005 Apr 28
0
(Fwd) Re: your membership of the AFT Email list
Totally understood. If you remain "on vacation" (we wish eh?!) and
get further messages like that from the list s'ware, just accept my
standing apologies and delete them.
Very welcome re letter!
Very best,
Chris
------- Forwarded message follows -------
Send reply to: "Alana O'C" <alanaoc at internode.on.net>
From: "Alana O'C"
2006 Nov 23
0
lasso for AFT model
Hi all,
I want to apply lasso method in AFT model. can anybody help me how to get
lasso estimate using AFT model.
Hossain
[[alternative HTML version deleted]]
2010 Oct 01
2
No translator path exists for channel type DAHDI (native 76) to 256
Hello,
We are having issues with a NEW Sangoma A108D:
-- Executing [691918892 at pbx1:1] Dial("SIP/xtravoip200-009d24b0",
"DAHDI/g0/691918892|30|m") in new stack
[Oct 1 10:04:43] WARNING[14171]: channel.c:3170 ast_request: No translator
path exists for channel type DAHDI (native 76) to 256
[Oct 1 10:04:43] WARNING[14171]: app_dial.c:1237 dial_exec_full: Unable to
create
2010 May 28
3
Gelman 2006 half-Cauchy distribution
Hi,
I am trying to recreate the right graph on page 524 of Gelman's 2006
paper "Prior distributions for variance parameters in hierarchical
models" in Bayesian Analysis, 3, 515-533. I am only interested, however,
in recreating the portion of the graph for the overlain prior density
for the half-Cauchy with scale 25 and not the posterior distribution.
However, when I try:
2011 May 02
3
ID parameter in model
Hello,
I am apparently confused about the use of an id parameter for an event
history/survival model, and why the EHA documentation for aftreg does
not specify one. All assistance and insights are appreciated.
Attempting to specifiy an id variable with the documentation example
generates an "overlapping intervals" error, so I sorted the original
mort dataframe and set subsequent entry
2002 Jun 28
1
Problem in optim(method="L-BFGS-B") (PR#1717)
Full_Name: Jörg Polzehl
Version: 1.5.1
OS: Windows 2000
Submission from: (NULL) (193.175.148.198)
When calculating MLE's in a variance component model using constrained
optimization, i.e. optim(...,method="L-BFGS-B",...) I observed an inproper
behaviour in cases where
the likelihood function was evalueted at the constraint. Parameters and value of
the
function at the constraint
2009 Dec 03
2
dahdi_tool shows no alarms, but no line connected
Hi,
I'm using Sangoma's wanpipe together with dahdi, all
software downloaded today at most recent version.
Hardware is Sangoma A104, a 4xE1 card.
Installation went well.
Anyway, wanrouter status shows a different result than
dahdi_tool or dahdi_scan.
I've just put a hardware loop on port 1. All the other
ports are open.
wanrouter status shows the expected result:
Device name |
2005 Feb 17
2
Sangoma A104 - D-Channel problem
Hello,
I have following problem with Sangoma A104 card:
CLI> pri show span 1
Primary D-channel: 16
Status: Provisioned, Down, Active
Switchtype: EuroISDN
Type: CPE
Window Length: 0/7
Sentrej: 0
SolicitFbit: 0
Retrans: 0
Busy: 0
Overlap Dial: 0
T200 Timer: 1000
T203 Timer: 10000
T305 Timer: 30000
T308 Timer: 4000
T313 Timer: 4000
N200 Counter: 3
NOTICE[16509]: chan_zap.c:7494 pri_dchannel: PRI
2003 Jul 25
5
named list 'start' in fitdistr
Hi R lovers!
I'd like to know how to use the parameter 'start' in the function
fitdistr()
obviously I have to provide the initial value of the parameter to optimize
except in the case of a certain set of given distribution
Indeed according to the help file for fitdistr
" For the following named distributions, reasonable starting values
will be computed if `start'
2006 Feb 01
1
Cauchy distribution limits
I have question (curiosity) regarding returned values of R's qcauchy
() function,
for nonexceedance probability (F). It seems the ideal returned range
of cauchy distribution should be [-Inf,Inf].
For F=0
> qcauchy(0)
[1] -Inf
but for F=1
> qcauchy(1)
[1] 8.16562e+15
It seems to me that the proper return value should be Inf???
For default (location=0,scale=1) quantile function of
2011 Apr 18
1
A101DE Sangoma Card in AsteriskNow 1.7.1
Hi,
I have A101DE Sangoma Card(
http://www.sangoma.com/products/hardware_products/digital_voice_and_data_networking/a101.html
)
lspci shows as 03:04.0 Network controller: Sangoma Technologies Corp.
A200/Remora FXO/FXS Analog AFT card
[root at asterisk ~]# lspci -vvv -s 03:04.0
03:04.0 Network controller: Sangoma Technologies Corp. A200/Remora FXO/FXS
Analog AFT card
Subsystem: Unknown device