Displaying 20 results from an estimated 6000 matches similar to: "regression problem"
2004 Apr 05
1
Cochrane-Orcutt
hi everybody
i'm looking for a function to estimate a regression model via the Cochrane
Orcutt method
thanks
2004 Feb 18
4
How to repeat a procedure
Hello,
1. After I generate a 100x50 matrix by x3<-matrix(0,100,50);for (i in
1:100) {x1<-rpois(50, mu[i]);x2<-x1; x2[runif(50)<.01]<-0; x3[i,]<-x2},
2. I want to calculate means and sample variances of each row and create a
new matrix 100x2;
3. I then want to repeat above procedure 500 times so that eventually I
will have 500 100x2 matrices.
Would someone mind helping me to
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
2007 Jan 04
1
need help with debug package
Hi all,
I met a problem while using the debug package, I have the following program:
mainfun<- function(){
beta<-1
result<-subfun(beta+x)
}
subfun<-function(expr){
y <- eval(expr, envir=list(x=c(1,2)),enclos = parent.frame())
return(y)
}
I have no problem using this program without calling the debug
2003 Jul 08
7
rbind question
Hi
I am trying to replicate a vector in n rows for comparison purposes with
another matrix.
foo <- c(1,2,3)
bar <- rbind(foo,foo) # does the trick for 2 rows
bar <- rbind(rep(foo,2)) # does something else
How do I generate a matrix with all rows=foo without writing 'foo' n times as
arg?
Thanks,
David
2002 Dec 06
3
ts startdate
Dear R-users,
I am facing a trivial problem when trying to parameterise the start date
of a time series object. I am working with monthly data (104) performing
n-steps-ahead (6) forecasts and using a fixed window size (36). At the
end of calculations I have a list that contains 69 forecasts.
I have no problems in fixing the window size by parametrization, e.g.
k<- control variable in a for
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
2011 Aug 15
1
accumulative grouping of time series
HI there,
Consider a data set like this:
> x <- data.frame(a=1:10, b=11:20, t=c(1,1,1,2,2,2,3,3,3,3))
> x
a b t
1 1 11 1
2 2 12 1
3 3 13 1
4 4 14 2
5 5 15 2
6 6 16 2
7 7 17 3
8 8 18 3
9 9 19 3
10 10 20 3
Here x$t is a vector of integers that represent a moment
in time. I would like to calculate a function of a & b at
each moment (t0), but using the rows
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
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
2008 Jun 04
2
array of arrays
Dear R users,
I want to calculate the bias and variance of an estimator for several values
of two parameters a and b.
For example :
b1 b2
a1 bias bias
variance variance
a2 bias bias
variance variance
Can one do array of arrays ? I have tried and it did not work.
Actually I would like to get this array for several values of the number of
observations. That
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
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