Displaying 20 results from an estimated 10000 matches similar to: "list of methods"
2018 Jun 26
0
list of methods
While it's easy to conceive of a utility that found all generics for
which there is no non-default method for a given class vector, it's
not clear it would be useful, because it depends on the nature of the
object. Surv objects are vector-like, so they need to implement the
"vector API", which is not formally defined. You could look at the
S4Vectors package or the date/time
2011 Dec 20
2
Extract BIC for coxph
Dear all,
is there a function similar to extractAIC based on which I can extract the
BIC (Bayesian Information Criterion) of a coxph model?
I found some functions that provide BIC in other packages, but none of them
seems to work with coxph.
Thanks,
Michael
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2004 Mar 05
1
Application of step to coxph using method="exact" (PR#6646)
Full_Name: John E. Kolassa
Version: Version 1.8.1
OS: Solaris
Submission from: (NULL) (128.6.76.36)
Stepwise model selection for coxph appears to fail with method="exact".
The code
step(coxph(Surv(1:100,rep(1,100))~factor(rep(1:4,25)),method="exact"))
produces the error message
Start: AIC= 733.07
Surv(1:100, rep(1, 100)) ~ factor(rep(1:4, 25))
Error in
2013 Jun 12
2
survreg with measurement uncertainties
Hello,
I have some measurements that I am trying to fit a model to. I also
have uncertainties for these measurements. Some of the measurements
are not well detected, so I'd like to use a limit instead of the
actual measurement. (I am always dealing with upper limits, i.e. left
censored data.)
I have successfully run survreg using the combination of well detected
measurements and limits,
2018 Jun 27
2
new behavior in model.response
I now understand the issue, which leads to a different and deeper issue which is "how to
assign a proper length to Surv objects".
> Surv(c(1,2,3), c(1,0,1))
[1] 1? 2+ 3
The above prints as 3 elements and is conceptually 3 elements. But if I give it length
method to return a 3 then I need a names method, and names<-? pays no attention to my
defined length. How do we conceive
2014 Mar 06
1
makepredictcall
An issue came up with the rms package today that makepredictcall would solve, and I was
going to suggest it to the author. But looking in the help documents I couldn't find any
reference to it. There is a manual page, but it does not give much aid in creating code
for a new transformation function. Did I miss something?
If not, I'd be willing to draft a paragraph about that which
2013 May 01
1
Trouble with methods() after loading gdata package.
Greetings to r-help land.
I've run into some program crashes and I've traced them back to methods()
behavior
after the package gdata is loaded. I provide now a minimal re-producible
example. This seems bugish to me. How about you?
dat <- data.frame(x = rnorm(100), y = rnorm(100))
lm1 <- lm(y ~ x, data = dat)
methods(class = "lm")
## OK so far
library(gdata)
2017 Sep 13
3
vcov and survival
Dear Terry,
Even the behaviour of lm() and glm() isn't entirely consistent. In both cases, singularity results in NA coefficients by default, and these are reported in the model summary and coefficient vector, but not in the coefficient covariance matrix:
----------------
> mod.lm <- lm(Employed ~ GNP + Population + I(GNP + Population),
+ data=longley)
>
2013 Oct 09
1
frailtypack
I can't comment on frailtypack issues, but would like to mention that coxme will handle
nested models, contrary to the statement below that "frailtypack is perhaps the only ....
for nested survival data".
To reprise the original post's model
cgd.nfm <- coxme(Surv(Tstart, Tstop, Status) ~ Treatment + (1 | Center/ID), data=cgd.ag)
And a note to the poster-- you should
2017 Oct 16
1
survival analysis - predict function
Hi
I'm trying to predict the values for a survreg object called
loglogistic_na. Here is the definition of loglogistic_na and following that
the syntax used for the predict function. But upon execution I don't get
any output. Not sure what I'm doing wrong:
loglogistic_na <- survreg(Surv(time_na,event_na) ~ t_na, dist="loglogistic")
summary(loglogistic_na)
2008 Nov 28
2
AIC function and Step function
I would like to figure out the equations for calculating "AIC" in both
"step() function" and "AIC () function". They are different. Then I
just type "step" in the R console, and found the "AIC" used in "step()
function" is "extractAIC". I went to the R help, and found:
"The criterion used is
AIC = - 2*log L + k *
2017 Sep 14
6
vcov and survival
>>>>> Martin Maechler <maechler at stat.math.ethz.ch>
>>>>> on Thu, 14 Sep 2017 10:13:02 +0200 writes:
>>>>> Fox, John <jfox at mcmaster.ca>
>>>>> on Wed, 13 Sep 2017 22:45:07 +0000 writes:
>> Dear Terry,
>> Even the behaviour of lm() and glm() isn't entirely consistent. In both cases,
2008 Apr 25
3
Use of survreg.distributions
Dear R-user:
I am using survreg(Surv()) for fitting a Tobit model of left-censored longitudinal data. For logarithmic transformation of y data, I am trying use survreg.distributions in the following way:
tfit=survreg(Surv(y, y>=-5, type="left")~x + cluster(id), dist="gaussian", data=y.data, scale=0, weights=w)
my.gaussian<-survreg.distributions$gaussian
2018 Jan 18
1
Time-dependent coefficients in a Cox model with categorical variants
First, as others have said please obey the mailing list rules and turn of
First, as others have said please obey the mailing list rules and turn off html, not everyone uses an html email client.
Here is your code, formatted and with line numbers added. I also fixed one error: "y" should be "status".
1. fit0 <- coxph(Surv(futime, status) ~ x1 + x2 + x3, data = data0)
2. p
2017 Nov 02
2
vcov and survival
>>>>> Fox, John <jfox at mcmaster.ca>
>>>>> on Thu, 14 Sep 2017 13:46:44 +0000 writes:
> Dear Martin, I made three points which likely got lost
> because of the way I presented them:
> (1) Singularity is an unusual situation and should be made
> more prominent. It typically reflects a problem with the
> data or the
2013 Nov 04
1
How to plot results of clmm()?
Dear list,
I'd like to create a visual plot of a clmm() I've fitted using the
'ordinal' package in R. It's possible to do this with a glm() by using
the 'effects' package. For example:
library(effects)
data(BEPS)
mod <- lm(political.knowledge ~ age + gender + vote, data=BEPS)
eff <- effect("age", mod, default.levels=100)
plot(eff,
2012 Nov 17
4
survfit & number of variables != number of variable names
This works ok:
> cox = coxph(surv ~ bucket*(today + accor + both) + activity, data = data)
> fit = survfit(cox, newdata=data[1:100,])
but using strata leads to problems:
> cox.s = coxph(surv ~ bucket*(today + accor + both) + strata(activity),
> data = data)
> fit.s = survfit(cox.s, newdata=data[1:100,])
Error in model.frame.default(data = data[1:100, ], formula = ~bucket + :
2009 Mar 08
2
survreg help in R
Hey all,
I am trying to use the survreg function in R to estimate the mean and
standard deviation to come up with the MLE of alpha and lambda for the
weibull distribution. I am doing the following:
times<-c(10,13,18,19,23,30,36,38,54,56,59,75,93,97,104,107,107,107)
censor<-c(1,0,0,1,0,1,1,0,0,0,1,1,1,1,0,1,0,0)
survreg(Surv(times,censor),dist='weibull')
and I get the following
2009 Dec 03
3
Tobit model fluid milk consumption
Hi all,
I'm from Brazil.
I fit a Tobit model to FLUID MILK CONSUMPTION (DEPENDENT VARIABLE) data
using survreg (attached).
I am confused about the output interpretation and I would like yours
explanations.
Thanks, Marcio Roberto Silva
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2024 Aug 26
9
specials and ::
The survival package makes significant use of the "specials" argument of terms(), before
calling model.frame; it is part of nearly every modeling function. The reason is that
strata argments simply have to be handled differently than other things on the right hand
side. Likewise for tt() and cluster(), though those are much less frequent.
I now get "bug reports" from the