Displaying 20 results from an estimated 2000 matches similar to: "extractAIC.coxph warning"
2017 Jun 08
1
stepAIC() that can use new extractAIC() function implementing AICc
I would like test AICc as a criteria for model selection for a glm using
stepAIC() from MASS package.
Based on various information available in WEB, stepAIC() use
extractAIC() to get the criteria used for model selection.
I have created a new extractAIC() function (and extractAIC.glm() and
extractAIC.lm() ones) that use a new parameter criteria that can be AIC,
BIC or AICc.
It works as
2013 May 16
2
Failure to join existing domain Windows 2003 Server domain
I compiled samba-4.0.5 from source on Ubuntu 12.04 and was following the instructions here:
http://wiki.samba.org/index.php/Samba4/HOWTO/Join_a_domain_as_a_DC
The exact command I executed was:
root at va-dc:/usr/local/samba# bin/samba-tool domain join win.starpoint.com<http://win.starpoint.com> DC -Uadministrator --realm=win.starpoint.com<http://win.starpoint.com>
2011 May 10
0
Help documentation in extractAIC
Hello.
The sentence in extractAIC's help <http://www.stat.psu.edu/~dhunter/R/html/stats/html/extractAIC.html> which discusses AIC's estimate of -2logL from RSS reads: "AIC only handles unknown scale and uses the formula n log (RSS/n) - n + n log 2pi - sum(log w) where w are the weights. Further AIC counts the scale estimation as a parameter in the edf and extractAIC does
2005 Jan 26
2
Source code for "extractAIC"?
Dear R users:
I am looking for the source code for the R function extractAIC. Type the
function name doesn't help:
> extractAIC
function (fit, scale, k = 2, ...)
UseMethod("extractAIC")
<environment: namespace:stats>
And when I search it in the R source code, the best I can find is in (R
source root)/library/stats/R/add.R:
extractAIC <- function(fit, scale, k = 2,
2011 Aug 04
0
extractAIC
Use extractAIC in frailty cox model (estimated with coxph function, gaussian
random effect) i obtaided
> extractAIC(fit.cox.f)
[1] 11.84563 8649.11736
but I don't know why I can't use the classic formulation of the AIC where
the degree of freedom are the number of the parameter (in my case 3).
--
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2017 Aug 23
0
MASS:::dropterm.glm() and MASS:::addterm.glm() should use ... for extractAIC()
Hi,
I have sent this message to this list the July, 7th. It was about a
problem in MASS package.
Until now there is no change in the devel version.
As the problem occurs in a package and not in the R-core, I don't know
if the message should have been sent here. Anyway, I have added a copy
to Pr Ripley.
I hope it could have been fixed.
Sincerely
Marc
Le 09/07/2017 ? 16:05, Marc Girondot via
2006 Aug 06
1
extractAIC using surf.ls
Although the 'spatial' documentation doesn't mention that extractAIC
works, it does seem to give an output.
I may have misunderstood, but shouldn't the following give at least
the same d.f.?
> library(spatial)
> data(topo, package="MASS")
> extractAIC(surf.ls(2, topo))
[1] 46.0000 437.5059
> extractAIC(lm(z ~ x+I(x^2)+y+I(y^2)+x:y, topo))
[1]
2009 Sep 22
0
AIC vs. extractAIC
Dear list,
I am confused about two functions in R: AIC(fm) and extractAIC(fm). What is
the difference between two and when do I have to use one over the other? I
have found the similar question previously and still not clear for me to
understand. I also looked at '?AIC' and '?extractAIC' in R, which is also
unclear. I pasted faked data set, fitting summary, and AICs.
Thank
2007 Dec 07
1
AIC v. extractAIC
Hello,
I am using a simple linear model and I would like to get an AIC value. I
came across both AIC() and extractAIC() and I am not sure which is best to
use. I assumed that I should use AIC for a glm and extractAIC() for lm,
but if I run my model in glm the AIC value is the same if I use AIC() on an
lm object. What might be going on? Did I interpret these functions
incorrectly?
Thanks,
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 May 24
1
bug in extractAIC.survreg (PR#6910)
Full_Name: Dave Ramsey
Version: 1.8.0
OS: win2000
Submission from: (NULL) (202.27.240.6)
there is a bug in extractAIC.survreg in library MASS.
A survreg model object has no component called "residuals". Hence
n <- length(fit$residuals)
returns 0 resulting in errors
workaround: replace
n <- length(fit$residuals)
with
n <- length(residuals(fit))
### sorry: error
2009 May 05
0
stepAICc function (based on MASS:::stepAIC.default)
Dear all,
I have tried to modify the code of MASS:::stepAIC.default(), dropterm() and addterm() to use AICc instead of AIC for model selection.
The code is appended below. Somehow the calculations are still not correct and I would be grateful if anyone could have a look at what might be wrong
with this code...
Here is a working example:
##
require(nlme)
model1=lme(distance ~ age + Sex, data =
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
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 *
2011 Feb 23
1
request for patch in "drop1" (add.R)
By changing three lines in drop1 from access based on $ to access
based on standard accessor methods (terms() and residuals()), it becomes
*much* easier to extend drop1 to work with other model types.
The use of $ rather than accessors in this context seems to be an
oversight rather than a design decision, but maybe someone knows better ...
In particular, if one makes these changes (which I am
1998 Feb 04
0
[J.Lindsey: Re: glm(.) / summary.glm(.); [over]dispersion and returning AIC..]
--Multipart_Wed_Feb__4_12:25:40_1998-1
Content-Type: text/plain; charset=US-ASCII
Jim, I am relating your message to R-devel.
This should be discussed in a broader audience;
I am not an expert on GLM's, I know you are
and others on this group also...
R-develers, please CC to Jim Lindsey (on this topic), since he hasn't
been part of the R-devel list for a while..
BTW: I will be gone
2017 Apr 04
0
Some "lm" methods give wrong results when applied to "mlm" objects
I had a look at some influence measures, and it seems to me that currently several methods handle multiple lm (mlm) objects wrongly in R. In some cases there are separate "mlm" methods, but usually "mlm" objects are handled by the same methods as univariate "lm" methods, and in some cases this fails.
There are two general patterns of problems in influence measures:
1998 Feb 03
2
glm(.) / summary.glm(.); [over]dispersion and returning AIC..
I have been implementing a proposal of Jim Lindsey for glm(.)
to return AIC values, and
print.glm(.) and print.summary.glm(.) printing them....
however:
>>>>> "Jim" == Jim Lindsey <jlindsey@luc.ac.be> writes:
Jim> The problem still remains of getting the correct AIC when the user
Jim> wants the scale parameter to be fixed. (The calculation should
2006 Sep 28
0
AIC in R
Dear R users,
According Brockwell & Davis (1991, Section 9.3, p.304), the penalty term for
computing the AIC criteria is "p+q+1" in the context of a zero-mean
ARMA(p,q) time series model. They arrived at this criterion (with this
particular penalty term) estimating the Kullback-Leibler discrepancy index.
In practice, the user usually chooses the model whose estimated index is
2010 Dec 26
1
Calculation of BIC done by leaps-package
Hi Folks,
I've got a question concerning the calculation of the Schwarz-Criterion
(BIC) done by summary.regsubsets() of the leaps-package:
Using regsubsets() to perform subset-selection I receive an regsubsets
object that can be summarized by summary.regsubsets(). After this
operation the resulting summary contains a vector of BIC-values
representing models of size i=1,...,K.
My problem