Displaying 20 results from an estimated 3000 matches similar to: "computing sum of indicator variables"
2004 Jan 09
3
ipred and lda
Dear all,
can anybody help me with the program below? The function predict.lda
seems to be defined but cannot be used by errortest.
The R version is 1.7.1
Thanks in advance,
Stefan
----------------
library("MASS");
library("ipred");
data(iris3);
tr <- sample(1:50, 25);
train <- rbind(iris3[tr,,1], iris3[tr,,2], iris3[tr,,3]);
test <- rbind(iris3[-tr,,1],
2007 Jun 20
2
Computing time differences
Dear R users,
I have a problem computing time differences using R.
I have a date that are given using the following format: 20080620.00, where
the 4 first digits represent the year, the next 2 ones the month and the last
2 ones the day. I would need to compute time differences between two vectors
of this given format.
I tried around trying to change this format into any type of time serie
2003 Jan 28
6
reading non-existent files
Dear R-experts
I would like to read all files from a directory, the files have names
"myname0001.txt" etc. I paste the directory plus file names and
use "read.delim()".
My problem is that some file names are missing, so I get an error
and my program stops.
Is there a way to check for a null pointer analogous to C, so that
I can simply skip non-existent filenames?
Please do
2006 Jan 04
1
AW: QLA2xxx URGEND
2003 Mar 07
5
Moving average
Hi,
Does anyone know if R has the functionality to calculate a simple moving
average. I cant seem
to find it in the help menu.
thanks,
Wayne
Dr Wayne R. Jones
Statistician / Research Analyst
KSS Group plc
St James''s Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713
KSS Ltd
A division of Knowledge Support Systems Group plc
Seventh
2003 Mar 28
4
Testing for randomness
Dear all,
Is there a test in R for the randomness of a sequence of observations (e.g.
to test the random number generator)? Specifically I am looking for autocorrelations
which are not necessarily linear in nature, which the acf function does
not seem to be flexible enough to detect as it tests for linear autocorrelation.
Thanks in advance,
Paul.
2004 Jul 19
5
converting character strings to eval
Hi there fellow R-users,
I'm stuck on this seemingly trivial problem.
All I want to coerce a character string into a command.
For example:
x<-rnorm(20)
y<-rnorm(20)
str<-"lm(y~x)"
I want to evaluate the "str" command.
I have tried
eval(as.expression(str))
But it doesn't seem to work. I am aware of the call command, but for
reasons I won't go
2004 Jun 09
3
market-basket analysis in R
Hi there fellow R-users,
Does anyone know if there exists a package for associated rules data mining
(market basket analysis) in R.
I have tried searching CRAN but with no luck.
Regards
Wayne
KSS Ltd
Seventh Floor St James's Buildings 79 Oxford Street Manchester M1 6SS England
Company Registration Number 2800886
Tel: +44 (0) 161 228 0040 Fax: +44 (0) 161 236 6305
2003 Nov 19
2
Correction for first order autocorrelation in OLS residuals
Hi there fellow R-users,
Can anyone tell me if there exits an R package that deals with serial
correlation in the residuals of an lm model.
Perhaps, using the Cochrane Orcutt or Praise Wilson methods?
Thanks,
Wayne
Dr Wayne R. Jones
Senior Statistician / Research Analyst
KSS Limited
St James's Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713
2003 May 14
1
ROracle problem with Oracle9i on Red Hat 8.0
Hi,
I have a problem executing "library(ROracle)" in R:
OS/Software:
Redhat 8.0, all available patches applied
Oracle 9i v9.2.0.1.0
R v1.7.0
ROracle v0.5-0
DBI v0.1-5
The compilation and installation of ROracle went fine. However when I try to
load ROracle I get the following:
>> library(ROracle)
>Error in dyn.load(x, as.logical(local), as.logical(now)) :
> unable
2004 Oct 04
7
Strange Matrix Multiplication Behaviour
Hi there fellow R-users,
Im seeing some strange behaviour when I multiply a vector by a matrix
Here is my script:
> tr
1 2 3 4 5 6
0.2217903 0.1560525 0.1487908 0.1671354 0.1590643 0.1471667
>
> ex1
a b c d e f
1 0.2309579 -3.279045 -0.6694697 -1.1024404 0.2303928 -1.5527404
2
2005 Jul 27
3
Asymmetric colors for heatmap
> Dear expeRts,
>
> Currently, my colors are as follows:
> mycol <-
> c("blue1","blue2","blue3","blue4","black","yellow4","yellow3","yellow2","y
> ellow1")
> heatmap(snp, Rowv=NA, Colv=NA, col=mycol)
>
> However, I would like to have the following colors:
> bright blue ->
2003 Apr 17
2
Testing for Stationarity of time series
Hi there,
Does anyone know if R has a function for testing whether a time series is
stationary??
Thanks in advance,
Wayne
Dr Wayne R. Jones
Statistician / Research Analyst
KSS Group plc
St James's Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713
KSS Ltd
A division of Knowledge Support Systems Group plc
Seventh Floor St James's
2003 Sep 02
2
FW: Creating a Package with Windows XP.
> Hi there fellow R-Users,
>
> I am trying to use the "package.skeleton" to create my own package with
> R.1.7.1 on Windows XP Professional.
> I have followed the package.skeleton example and have downloaded the
> necessary files found at http://www.stats.ox.ac.uk/pub/Rtools/tools.zip.
>
> and perl5, available via
2003 Sep 04
3
: RODBC column length>255
Hello there fellow R-users,
I am using the RODBC functionality to query a database. I am trying to read
in a columns of strings which have a character field lengths greater than
255.
The data.frame that I recieve back from the RODBC query only contains the
first 255 characters (the rest having been truncated).
Any help on how to solve this problem would be greatly appreciated.
Reagrds
Wayne
2005 Jul 12
3
bug in chdir option of source
I'm on R 2.1.0.
In the "source" function there is a bug preventing the proper use of the
chdir option (which simply doesn't work).
The problem is that in the function the following line occurs:
file <- file(file, "r", encoding = encoding)
This overwrites the variable "file" and later causes the check
if (chdir && is.character(file)
2004 Feb 12
1
Almost Ideal Demand System
Hi there fellow R users,
Has anyone got an R example of applying an Ideal demand system, possibly
using the library systemfit??
Thanks
Wayne
Dr Wayne R. Jones
Senior Statistician / Research Analyst
KSS Limited
St James's Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713
KSS Ltd
Seventh Floor St James's Buildings 79 Oxford Street
2003 Apr 03
1
Na handing with time series objects
Hello All,
Does anyone out there know a way to decompose time series objects with
missing values.
A simple "na.omit" will not work since it does not preserve the time
differences between succesive observations.
Thanks in advance,
Wayne
Dr Wayne R. Jones
Statistician / Research Analyst
KSS Group plc
St James''s Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161
2003 Apr 09
2
Building function libraries
HI there,
Does anyone how I can build my own library of R functions?
Regards,
Wayne
Dr Wayne R. Jones
Statistician / Research Analyst
KSS Group plc
St James's Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713
KSS Ltd
A division of Knowledge Support Systems Group plc
Seventh Floor St James's Buildings 79 Oxford Street Manchester M1
2004 Apr 02
1
GARCH
Hi there fellow R-Users,
Can anyone recommend a good book on the theory and practice of applying
GARCH models.
Also, does any one know of any R related subject material in addition to
library(tseries).
Regards
Wayne
Dr Wayne R. Jones
Senior Statistician / Research Analyst
KSS Limited
St James's Buildings
79 Oxford Street
Manchester M1 6SS
Tel: +44(0)161 609 4084
Mob: +44(0)7810 523 713