Displaying 20 results from an estimated 20000 matches similar to: "R-help Digest, Vol 118, Issue 20"
2012 Dec 19
0
Fitting a predefined classification tree
Hi,
I've searched R-help and haven't found an answer. I have a set of data from which I can create a classification tree using
rpart. However, what I'd like to do is predefine the blank structure of the binary tree (i.e., which nodes to include) and then use a package like rpart to fit for the optimal splitting criteria at each of the predefined nodes.
Does such a package exist?
2009 May 26
0
cross-validation in rpart
Dear R users,
I know cross-validation does not work in rpart with user defined split
functions. As Terry Therneau suggested, one can use the xpred.rpart function
and then summarize the matrix of the predicted values into a single
"goodness" value.
I need only a confirmation: set for example xval=10, if I correctly
understood a single column of the matrix obatined by xpred.rpart gives
2004 Feb 17
0
New package -- mvpart
The package mvpart is now available.
mvpart includes partitioning based on (1) multivariate numeric responses and
(2) dissimilarity matrices.
The package mvpart is a modification of rpart --
-- authors of original: Terry M Therneau and Beth Atkinson
<atkinson at mayo.edu>, and
R port of rpart Brian Ripley <ripley at stats.ox.ac.uk>.
Includes some modified routines from vegan --
2004 Feb 17
0
New package -- mvpart
The package mvpart is now available.
mvpart includes partitioning based on (1) multivariate numeric responses and
(2) dissimilarity matrices.
The package mvpart is a modification of rpart --
-- authors of original: Terry M Therneau and Beth Atkinson
<atkinson at mayo.edu>, and
R port of rpart Brian Ripley <ripley at stats.ox.ac.uk>.
Includes some modified routines from vegan --
2005 Oct 18
1
Memory problems with large dataset in rpart
Dear helpers,
I am a Dutch student from the Erasmus University. For my Bachelor thesis I
have written a script in R using boosting by means of classification and
regression trees. This script uses the function the predefined function
rpart. My input file consists of about 4000 vectors each having 2210
dimensions. In the third iteration R complains of a lack of memory,
although in each iteration
2010 Mar 12
1
using xval in mvpart to specify cross validation groups
Dear R's
I'm trying to use specific rather than random cross-validation groups
in mvpart.
The man page says:
xval Number of cross-validations or vector defining cross-validation groups.
And I found this reply to the list by Terry Therneau from 2006
The rpart function allows one to give the cross-validation groups explicitly.
So if the number of observations was 10, you could use
2020 Sep 25
1
Extra "Note" in CRAN submission
When I run R CMD check on the survival package I invariably get a note:
...
* checking for file ?survival/DESCRIPTION? ... OK
* this is package ?survival? version ?3.2-6?
* checking CRAN incoming feasibility ... NOTE
Maintainer: ?Terry M Therneau <therneau.terry at mayo.edu>?
...
This is sufficient for the auto-check process to return the following failure message:
Dear maintainer,
2012 Sep 27
1
erasing a polygon
I'm updating some (very) old code, and one particular option of its plot method depends on
a once-was-true trick
polygon(x, y, border=TRUE, col=0)
polygon(x, y, border=TRUE, density=0)
would draw the polygon AND erase whatever was underneath it back to background color.
Is there a reliable way to do this with the current R (standard graphics)?
Terry Therneau
PS For the
2024 Jun 26
2
Fixing a CRAN note
I am trying to clear up all the "NOTE"s before a CRAN submission, but am a bit confused
about this one.?? What is it complaining about -- that it doesn't like my name?
...
* checking for file ?deming/DESCRIPTION? ... OK
* this is package ?deming? version ?1.4-1?
* checking CRAN incoming feasibility ... [7s/18s] NOTE
Maintainer: ?Terry Therneau <therneau.terry at mayo.edu>?
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
2010 Apr 11
0
plotting rpart objects, text.rpart, fancy option
I have created plots of rpart objects with the fancy option for text.rpart
("fancy" creates ellipses and rectangles and labels branches with splitting
criteria). The ellipses and rectangles are supposed to "interrupt" the tree
lines (as seen in Therneau and Atkinson 1997, page 48, Fig. 18,
http://www.mayo.edu/hsr/techrpt/61.pdf), but they do not, even when I use
Therneau and
2014 Aug 18
0
patch for rpart
On 08/14/2014 05:00 AM, r-devel-request at r-project.org wrote:
> Dear list
>
>
> For my work, it would be helpful if rpart worked seamlessly with an
> empty model:
>
> library(rpart); rpart(formula=y~0, data=data.frame(y=factor(1:10)))
>
> Currently, an unrelated error (originating from na.rpart) is thrown.
>
> At some point in the near future, I'd like to
2001 Jul 26
0
tree and rpart
There have been various messages about packages tree and rpart whilst
I have been travelling, and I have now prepared updates.
tree
====
Tree is one of the oldest packages on CRAN (Feb 2000 apart from adding
the maintainer field), and I had been hoping that it would fade away
in favour of rpart.
1) sys.parent needed to be replaced by parent.frame in all but the
most recent R (post 1.3.0).
2019 Sep 06
2
install_github and survival
I cloned therneau/survival and the installation failed since there is no definition for exported function survfit().
A file seems to be missing - there is survfit0() and survfit0.R but, compared to CRAN, no survfit.R.
Georgi Boshnakov
----------------------------------------------------------------------
Message: 1
Date: Thu, 05 Sep 2019 12:53:11 -0500
From: "Therneau, Terry M.,
2016 Apr 15
0
simple interactions
Dear Terry,
Does fitting group + age:group instead of age*group solves your problem?
Best regards,
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and
Forest
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070 Anderlecht
Belgium
To call in the statistician after the experiment is done may be no more
2011 Jan 11
0
Some questions concerning survival tree analysis using the rpart module
All the documentation that I have on survival splitting is found in the
technical report you mention. However, there is both a short form and a
long form of this on our web site, did you get the larger one (52
pages)? I admit it is not a lot.
There are no other split algorithms implimented for survival data. It
would be possible to add your own. Attached is a slightly updated
version of the
2016 Mar 17
0
match and unique
Hi Terry,
On 03/16/2016 08:03 AM, Therneau, Terry M., Ph.D. wrote:
> Is the phrase "index <- match(x, sort(unique(x)))" reliable, in the
> sense that it will never return NA?
This is assuming that match() and unique() will never disagree on
equality between 2 floating point values. I believe they share some
code internally (same hashing routine?), so maybe it's reliable.
2017 Dec 29
0
winbuilder warning message wrt function pointers
You can legally cast a function pointer to another function pointer, where
the signatures differ. (It is not legal to cast between data and function
pointers.)
I would make typedefs for the various signatures, as the casting syntax is
more
readable then.
Bill Dunlap
TIBCO Software
wdunlap tibco.com
On Fri, Dec 29, 2017 at 10:13 AM, Therneau, Terry M., Ph.D. <
therneau at mayo.edu> wrote:
2006 May 12
2
reusing routines
I've created some Splus code for a microarray problem that
- needed to be in C, to take advantage of some sparse matrix
properties
- uses a cholesky decompostion as part of the computation
For the cholesky, I used the cholesky2 routine, which is a part of the
survival library. It does just what I want and I'm familiar with it (after
all, I wrote it).
In Splus, this all works
2011 Jan 24
1
How to measure/rank ?variable importance when using rpart?
--- included message ----
Thus, my question is: *What common measures exists for ranking/measuring
variable importance of participating variables in a CART model? And how
can
this be computed using R (for example, when using the rpart package)*
---end ----
Consider the following printout from rpart
summary(rpart(time ~ age + ph.ecog + pat.karno, data=lung))
Node number 1: 228 observations,