Displaying 20 results from an estimated 300 matches similar to: "pcaNNet confusion"
2010 Nov 23
5
cross validation using e1071:SVM
Hi everyone
I am trying to do cross validation (10 fold CV) by using e1071:svm method. I
know that there is an option (?cross?) for cross validation but still I
wanted to make a function to Generate cross-validation indices using pls:
cvsegments method.
#####################################################################
Code (at the end) Is working fine but sometime caret:confusionMatrix
2011 Mar 16
1
object not found whilst loading namespace
I've been updating a package and, when installing a local devel
version, I get an error "object 'confusionMatrix' not found whilst
loading namespace". Looking around online, it appears that this might
be related to loading a specific RData file, but it doesn't seem to be
the case AFAICT.
I've installed the devel version in the last week without issues and
the
2012 Aug 15
2
sensitivity and specificity in svyglm??
Hello,
As obtained from a table svyglm clasificaion, sensitivity and specificity. The funtion ConfusionMatrix () of the library (caret)
gives these results but not how to apply it to svyglm.
thanks
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2018 Feb 26
3
Random Seed Location
Hi all,
For some odd reason when running na?ve bayes, k-NN, etc., I get slightly
different results (e.g., error rates, classification probabilities) from run
to run even though I am using the same random seed.
Nothing else (input-wise) is changing, but my results are somewhat different
from run to run. The only randomness should be in the partitioning, and I
have set the seed before this
2018 Feb 27
0
Random Seed Location
In case you don't get an answer from someone more knowledgeable:
1. I don't know.
2. But it is possible that other packages that are loaded after set.seed()
fool with the RNG.
3. So I would call set.seed just before you invoke each random number
generation to be safe.
Cheers,
Bert
Bert Gunter
"The trouble with having an open mind is that people keep coming along and
sticking
2018 Mar 04
3
Random Seed Location
On Mon, Feb 26, 2018 at 3:25 PM, Gary Black <gwblack001 at sbcglobal.net>
wrote:
(Sorry to be a bit slow responding.)
You have not supplied a complete example, which would be good in this
case because what you are suggesting could be a serious bug in R or a
package. Serious journals require reproducibility these days. For
example, JSS is very clear on this point.
To your question
>
2018 Mar 04
0
Random Seed Location
Thank you, everybody, who replied! I appreciate your valuable advise! I will move the location of the set.seed() command to after all packages have been installed and loaded.
Best regards,
Gary
Sent from my iPad
> On Mar 4, 2018, at 12:18 PM, Paul Gilbert <pgilbert902 at gmail.com> wrote:
>
> On Mon, Feb 26, 2018 at 3:25 PM, Gary Black <gwblack001 at sbcglobal.net>
>
2008 Sep 06
3
how to address last and all but last column in dataframe
Dear R-colleagues,
another question from a newbie: I am creating a lot of simple
pivot-charts from my raw data using the reshape-package. In these charts
we have medical doctors judging videos in the columns and the videos
they judge in the rows. Simple example of chart/data.frame "input" with
two categories 1/0:
video 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
1 1 0 0
2018 Mar 04
2
Random Seed Location
The following helps identify when .GlobalEnv$.Random.seed has changed:
rng_tracker <- local({
last <- .GlobalEnv$.Random.seed
function(...) {
curr <- .GlobalEnv$.Random.seed
if (!identical(curr, last)) {
warning(".Random.seed changed")
last <<- curr
}
TRUE
}
})
addTaskCallback(rng_tracker, name = "RNG tracker")
EXAMPLE:
>
2009 Jan 25
0
caret version 4.06 released
Version 4.06 of the caret package was sent to CRAN.
caret can be used to tune the parameters of predictive models using
resampling, estimate variable importance and visualize the results.
There are also various modeling and "helper" functions that can be
useful for training models. caret has wrappers to over 50 different
models for classification and regression. See the package
2009 Jan 25
0
caret version 4.06 released
Version 4.06 of the caret package was sent to CRAN.
caret can be used to tune the parameters of predictive models using
resampling, estimate variable importance and visualize the results.
There are also various modeling and "helper" functions that can be
useful for training models. caret has wrappers to over 50 different
models for classification and regression. See the package
2018 Mar 04
0
Random Seed Location
On 04/03/2018 5:54 PM, Henrik Bengtsson wrote:
> The following helps identify when .GlobalEnv$.Random.seed has changed:
>
> rng_tracker <- local({
> last <- .GlobalEnv$.Random.seed
> function(...) {
> curr <- .GlobalEnv$.Random.seed
> if (!identical(curr, last)) {
> warning(".Random.seed changed")
> last <<- curr
2016 Aug 31
1
A bug in the R Mersenne Twister (RNG) code?
On 30 August 2016 at 18:29, Duncan Murdoch wrote:
| I don't see evidence of a bug. There have been several versions of the
| MT; we may be using a different version than you are. Ours is the
| 1999/10/28 version; the web page you cite uses one from 2002.
|
| Perhaps the newer version fixes some problems, and then it would be
| worth considering a change. But changing the default RNG
2008 Aug 12
3
aligned memory allocation in C
Hi,
I'm currently R porting SF Mersenne Twister algorithm of Matsumoto and
Saito. To get the full power of their code, I want to use their
fonction fill_array32 which need aligned memory. That is to say I need
to use the C function memalign on windows, posix_memalign on linux and
classic malloc on Mac OS. In 'writing R extenstion', they recommand to
use R_alloc function to
2008 Aug 12
3
aligned memory allocation in C
Hi,
I'm currently R porting SF Mersenne Twister algorithm of Matsumoto and
Saito. To get the full power of their code, I want to use their
fonction fill_array32 which need aligned memory. That is to say I need
to use the C function memalign on windows, posix_memalign on linux and
classic malloc on Mac OS. In 'writing R extenstion', they recommand to
use R_alloc function to
2009 May 12
4
different results on linux and windows
Dear R experts,
we are preparing an R-package to compute the Oja Median which contains
some C++ code in which random numbers are needed. To generate the random
numbers we use the following Mersenne-Twister implementation:
// MersenneTwister.h
// Mersenne Twister random number generator -- a C++ class MTRand
// Based on code by Makoto Matsumoto, Takuji Nishimura, and Shawn Cokus
// Richard J.
2009 Jul 11
1
hands-on classification tutorial needed...
Hi all,
I am doing binary classification and want to improve the
classification results on imbalanced response data.
Currently the performance is poor. Are there ways I could improve the
performance?
I could either try different classification methodologies, or try
exploring the data more, and throwing away noisy data, and manipulate
the data more before sending into the classifiers.
I was
2010 Jun 08
2
cross-validation
Hi
I want to do leave-one-out cross-validation for multinomial logistic regression in R. I did multinomial logistic reg. by package nnet in R. How I do validation? by which function?
response variable has 7 levels
please help me
Thanks alot
Azam
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2007 Dec 14
2
train nnet
Hi R-helpers,
Can some one tell me how to train 'mynn' of this type?:
mynn <- nnet(y ~ x1 + ..+ x8, data = lgist, size = 2, rang = 0.1,
decay = 5e-4, maxit = 200)
I assume that this nn is untrained, and to train I have to split the
original data into train:test data set,
do leave-one-out refitting to refine the weights (please straighten
this up if I was wrong).
I just don't know
2003 Jun 12
1
Tested Random Number Generator
Dear All,
The editor of a journal to which I had submitted a publication asked
whether R has a "tested random number generator." My paper included
Monte Carlo simulations generating random normal and random chi-square
values.
help(rnorm) lists
Wichura, M. J. (1988) Algorithm AS 241: The Percentage Points of
the Normal Distribution. Applied Statistics, 37, 477-484.
as a