Displaying 20 results from an estimated 30000 matches similar to: "arima/arima0 function"
2004 Jun 17
1
Error with arima()
Could someone please give a brief explanation, or pointer to an explanation,
of the following error:
> arima(ts.growth, order = c(1,0,0),include.mean=T)
Error in arima(ts.growth, order = c(1, 0, 0), include.mean = T) :
non-stationary AR part from CSS
and why it does not arise with
> arima0(ts.growth, order = c(1,0,0))
Many thanks
____________________________
Dr. Daniel P. Bebber
2009 May 04
0
questions about function arima0
Hi,
I work on order estimation for autoregressive processes and after some
inconsistencies cropped up I implemented the AIC criterion myself. Its
results do not match the implementation in R and there are a few
things I can not understand even after reading the source code of R.
I used the function called arima0 (with empty "ma" coeficient vector),
and I do not understand how some of
2001 Dec 16
3
Arima
I did a regression with ARMA errors using arima0 with
ari<-arima0(y,order=c(2,0,2),xreg=reg1,delta=-1)
or
ari<-arima0(y,order=c(2,0,2),xreg=reg1)
where reg1 is the matrix of the regressors and when I see diag(ari$var.coef)
I get negative terms. Do you know what this mean ?
I try to change transform.pars to 0 or 1 but this crash R on Windows.
Is it possible to test the significativity
2003 Jan 09
2
using arima() function
HI, there,
When i use R, i tried to use function arima(), it complains:
Error: couldn't find function "arima"
But when I type "help.search("arima") ",
I got arima() poped up..
arima(ts) ARIMA Modelling of Time Series
arima.sim(ts) Simulate from an ARIMA Model
arima0(ts) ARIMA Modelling of Time Series -- Preliminary
2001 Apr 24
1
ARIMA and GARCH
Hello,
I would like to study time series with ARIMA and GARCH models.
I installed R-Plus and its libraries but when I try to execute the function
arima0, It answers that the function does not exist.
Could you help me or give me references of papers dealing with arima and garch
in R-Plus?
Thanks
Beno?t,
___________________________________
Mr. Beno?t LACHERON
Rue de l'industrie, 44,
1040
2004 Aug 29
1
predict(arima)
Dear All,
R 1.9.1, Windows
When copying and pasting a few lines from the 'predict.Arima' help, I
get an error message:
> data(lh)
> predict(arima(lh, order = c(3,0,0)), n.ahead = 12)
Error in eval(expr, envir, enclos) : Object "xreg" not found
On the other hand, the following is OK:
> data(lh)
> predict(arima0(lh, order = c(3,0,0)), n.ahead = 12)
$pred
Time
2007 Mar 13
1
estimating an ARIMA model with constraints
Hi,
I am trying to estimate an ARIMA model in the case where I have some
specific knowledge about the coefficients that should be included in the
model. Take a classical ARIMA (or even ARMA) model:
P(B) X(t) = Q(B) epsilon(t),
where X(t) is the data, epsilon is a white noise, B is the backward operator
and P and Q are some polynoms. Additionally, assume that you know in advance
how P and Q
2003 Jul 31
1
R 1.7.1 arima0 problem
Hi, I'm trying to go through the examples for function
arima0() in ts package, i.e,
>data(lh)
>arima0(lh, order = c(1,0,0))
each time the call to arima0() causes a segmentation
fault. I checked the earlier version (1.1.1) of R,
the function arima0 works fine.
Tracing the call indicates that the function
"setup_starma" (in pacf.c under ts) interprets
the addresses of the
2011 Jul 20
0
The C function getQ0 returns a non-positive covariance matrix and causes errors in arima()
Hi,
the function makeARIMA(), designed to construct some state space
representation of an ARIMA model, uses a C function called getQ0,
which can be found at the end of arima.c in R source files (library
stats). getQ0 takes two arguments, phi and theta, and returns the
covariance matrix of the state prediction error at time zero. The
reference for getQ0 (cited by help(arima)) is:
2004 May 24
0
Seasonal ARIMA question - stat package (formerly ts)
To whom it may concern:
I am trying to better understand the functionality of 'R' when making
arima predictions to avoid any "Black Box" disadvantages.
I'm fitting a seasonal arima model using the following command (having
already loaded 'stat' package).
arimaSeason <-
arima(Data,order=c(1,0,1),seasonal=list(order=c(1,0,1),period=12))
I can then generate
2010 Sep 11
0
outputting arima models
sseq <- c(1, seq(5, 120, by = 5))
for(i in 1:length(sseq)){
assign(paste("arima", i, sep=""), arima0(data.ts[sseq[i]:(sseq[i]+115)],
order=c(1,1,1)))
}
pred1 = predict(arima1, n.ahead = 5, se.fit = TRUE)$pred
how do I traverse the arima models so I repeat the above prediction
procedure(bold) on all arima models. Also, how do i automatically create
one huge vector of the
2011 Apr 09
0
stats/arima.c memory allocation
Looking at the arima.c code related to arima fitting I noticed that the code
is mainly a merge of:
- Gardner, G, Harvey, A. C. and Phillips, G. D. A. (1980) Algorithm AS154.
An algorithm for exact maximum likelihood estimation of
autoregressive-moving average models by means of Kalman filtering. Applied
Statistics 29, 311–322.
- Jones, R. H. (1980) Maximum likelihood fitting of ARMA models to
2010 Oct 26
0
problem with arima() function
Hi
I posted this problem yesterday but didn't get a reply so I try again today.
I hope someone can help me with this.
thank you very much for the help
cheers
Benedikt
I would like to use arima () to find the best arima model for a time
series. The default in arima apparently is to use conditional sum of
squares to find the starting values and then use ML for the
2009 Apr 22
1
arima
Hi,
I have a suggestion for the fonction arima and arima0. I think you
should not call the constant an intercept because it creates confusion.
It is not really an intercept but a mean. For an AR(1) the intercept mu
should be defined as:
X(t)=mu + phi X(t-1) + e(t)
What you call intercept mu is rather defined as
(X(t)-mu) = phi (X(t-1)-mu)) + e(t)
which is not a common way to define an
2000 Feb 29
0
Re: arima in ts.
> From: "Krassimir Krastev" <krastev at fas.harvard.edu>
> To: "R-help" <r-help at stat.math.ethz.ch>
> Date: Tue, 29 Feb 2000 11:56:49 -0500
> X-Priority: 3 (Normal)
> X-MSMail-Priority: Normal
> Importance: Normal
> X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6600
>
> Does anyone know of any comprehensive literature (like a
2009 Mar 06
0
modifying a built in function from the stats package (fixing arima) (CONCLUSIONS)
Thanks a lot to everybody that helped me out with this.
Conclusions:
(1)
In order to edit arima in R:
>fix(arima)
or alternatively:
>arima<-edit(arima)
(2)
This is not contained in the "Introduction to R" manual.
(3)
A "productive" fix of arima is attached (arma coefficients printed out and
error catched so that it doesn't halt parent loops to search for
2007 Aug 23
1
Estimate Intercept in ARIMA model
Hi, All,
This is my program
ts1.sim <- arima.sim(list(order = c(1,1,0), ar = c(0.7)), n = 200)
ts2.sim <- arima.sim(list(order = c(1,1,0), ar = c(0.5)), n = 200)
tdata<-ts(c(ts1.sim[-1],ts2.sim[-1]))
tre<-c(rep(0,200),rep(1,200))
gender<-rbinom(400,1,.5)
x<-matrix(0,2,400)
x[1,]<-tre
x[2,]<-gender
fit <- arima(tdata, c(1, 1, 0), method = "CSS",xreg=t(x))
2003 Sep 01
1
Arima with an external regressor
Hello,
Does anybody know if the function arima with an external regressor (xreg)
applies the auto correlation on the dependant variable or on the residuals.
In comparison with SAS (proc autoreg), it seems that the auto correlation
applies on the residuals but i'd like to have the confirmation.
I want to estimate:
Y[t] = a[1]*X[t] + a[2] + E[t]
with E[t]=b[1]*E[t-1]
Should I use :
arima(Y,
1999 Nov 07
2
arima0() (PR#314)
Full_Name: Ahmad Abu Hammour
Version: rw0651
OS: windows 95
Submission from: (NULL) (63.23.128.44)
Although I know that "ts package" is preliminary, I wanted to compare the
results from R and SPSS. I ran ARIMA(2,1,2) in both softwares. I got NaN in
standard errors of coefficients from R and real figures from SPSS. I changed
"delta" in R to match that used by SPSS, I received