Displaying 20 results from an estimated 2000 matches similar to: "rolling n-step predictions for ARIMA models"
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
2002 Jan 30
1
Hi,
Hi,
Sorry for the confusion.
I would like to estimate a model wherein
the marginals of z with respect to w1 and w2
are smooth functions of x and y. I have data
on z, x, y, w1 and w2.
so E[dz/dw1] = f(x,y) and E[dz/dw2] = g(x,y)
and I would like to estimate f(x,y) and g(x,y)
I suppose I could try to fit something more general
using projection pursuit, but the nature of the problem
suggests
2002 Jan 28
6
Almost a GAM?
Hello:
I sent this question the other day with the wrong subject
heading and couple typos, with no response. So,
here I go again, having made those corrections.
I would like to estimate, for lack of a better description,
a partially additive non-parametric model with the following
structure:
z~ f(x,y):w1 + g(x,y):w2 + e
In other words, I'd like to estimate the marginals with
respect to
2002 Jan 25
1
Fw: Summary for Distance matrix by cosine?
Dear all,
below you find enclosed my message from January 9th and my program
(attention: beginner).
Thanks for both answers! a. However, as far as I know the cosine is not the
same as the Pearson correlation (only in special cases).
b. Reid Huntsinger's hint was very useful, however I had to transpose the
matrix first, for I want to calculate the distance of the _rows_.
Regards,
Petra
2003 Jul 31
1
spatial statistics vs. spatial econometrics
Dear R users,
I am putting together reading and resources lists for spatial statistics and spatial econometrics and am looking for some pointers from more experienced practitioners.
In particular, I find two "camps" in spatial modelling, and am wondering which approach is better suitied to which situation.
The first camp is along the lines of Venables and Ripley's Chapter 14
2012 Aug 01
1
Odd Results when using R's auto.arima function
Good morning everyone,
I have attached an Excel file that contains a macro from which I call and
use R's auto.arima function to generate forecasts. The program runs
perfectly and it gets me the results; however, those results are pretty
unusual. I also tried using the auto.arima function directly in the R
console and still get weird results.
The results are shown in columns AB, AC and AD
2009 Mar 05
3
Time Series - ARIMA differencing problem
Hi,
I have been using this website (
http://www.stat.pitt.edu/stoffer/tsa2/Rissues.htm
http://www.stat.pitt.edu/stoffer/tsa2/Rissues.htm ) to help me to fit ARIMA
models to my data. At the moment I have two possible methods to use.
Method 1
If I use
arima(ts.data, order=c(1,2,0), xreg=1:length(ts.data))
then the wrong value for the intercept/mean is given (checked on SPSS and
Minitab) and
2007 Jan 24
1
n step ahead forecasts
hello,
I have a question about making n step ahead forecasts in cases where test
and validation sets are availiable. For instance, I would like to make one
step ahead forecasts on the WWWusage data so I hold out the last 10
observations as the validation set and fit an ARIMA model on the first 90
observations. I then use a for loop to sequentially add 9 of the holdout
observations to make 1
2009 Nov 27
0
VAR forecasts and out-of-sample prediction
Dear users,
I am struggling with this issue. I want to estimate a VAR(1) for three
variables, say beta1 beta2 beta3, using monthly observations from January
1984 to September 2009. In-sample period January 1984 to December 2003,
out-of-sample January 2004 to September 2009. This is what I have done at
the moment
2000 Nov 08
3
state-space models and kalman filter
Hello again,
A different but related question to my last one:
Does anyone know if one can easily estimate state-space models
using ML and the kalman filter using R? I would be especially
interested in a relatively flexible function that would allow for
estimation
of hyperparameters, or could be made to do so.
Thanks
Michael J. Roberts
Resource Economics Division, PMT
USDA-ERS
202-654-5557
2003 Apr 16
0
arima function - estimated coefficients and forecasts
I'm using the arima function to estimate coefficients and also using
predict.Arima to forecast. This works nicely and I can see that the
results are the same as using SAS's proc arima.
I can also take the coefficent estimates for a simple model like
ARIMA(2,1,0) and manually compute the forecast. The results agree to 5
or 6 decimal places. I can do this for models with and without
2002 Feb 27
3
winsock 16 BIT
Hi!
In October I worked with a client-server (using winsock.dll) 16 bit
aplication
emulated in wine (Not using ODBC), it worked fine. This aplication needs
to connect to a
server using port ctsql 5557/tcp, this service is in my /etc/services.
And wine made all realy fine (Version 20011108). With the release
20011226 (I think)started the problem. Something changed with winsock
16-bit.
I've
2007 Nov 18
2
problem with tdm2400p configuration
Hi i have a tdm2400p and installed asterisk 1.4.11 with zaptel 1.4.5
im having an error message when in running asterisk with the tdm card
in.
here's the error from the console of asterisk:
[Nov 18 10:30:44] ERROR[5557]: chan_zap.c:7489 mkintf: Unable to get
span status: Inappropriate ioctl for device
[Nov 18 10:30:44] ERROR[5557]: chan_zap.c:10466 build_channels: Unable
to register channel
2010 Mar 19
1
Arima forecasting
Hello everyone,
I'm doing some benchmark comparing Arima [1] and SVR on time series data.
I'm using an out-of-sample one-step-ahead prediction from Arima using
the "fitted" method [2].
Do someone know how to have a two-steps-ahead forecast timeseries from Arima?
Thanks,
Matteo Bertini
[1] http://robjhyndman.com/software/forecast
[2] AirPassengers example on page 5
2010 Sep 13
0
Adding dummy variable "zero/one" in ARIMA model in R
Dear R gurus,
How do I add dummy variable zero/ one in the ARIMA model " both in the
in-sample and outside the sample(forecasts)?
Regards
Peter
South Africa
Tell: +2712 422 7357
Please Note: This email and its contents are subject to our email legal notice which can be viewed at http://www.sars.gov.za/Email_Disclaimer.pdf
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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
2007 Dec 24
2
ARIMA problem
Hi,
This is regarding the ARIMA model.
I am having time series data of stock of 2000 values. Using the ARIMA model
in R, I want the forcasted values for next 36 time points.
However when I run this model in R, I am getting same value for all 36 time
points.
I have tried to fit the data with ARIMA model by changing the parameters
p,d,q after looking at the errors and other criteria for
2012 May 18
0
Forecast package, auto.arima() convergence problem, and AIC/BIC extraction
Hi all,
First:
I have a small line of code I'm applying to a variable which will be
placed in a matrix table for latex output of accuracy measures:
acc.aarima <- signif(accuracy(forecast(auto.arima(tix_ts,
stepwise=FALSE), h=365)), digits=3).
The time series referred to is univariate (daily counts from 12-10-2010
until 5-8-2010 (so not 2 full periods of data)), and I'm working on
2009 Jun 04
2
Import ARIMA coefficients
Hello,
I need to know how to import ARIMA coefficients. I already determined the coefficients of the model with other software, but now i need to do the forecast in R.
For Example: I have a time series named x
and i have fitted an ARIMA(1,0,1) (with other software)
AR coef = -.172295
MA coef = .960043
(i know that this is not a good model, it's just an example)
I try to
2012 Apr 17
2
Manually reconstructing arima model from coefficients
Colleagues
I am a new to R but already love it.
I have the following problem:
I fitted arima model to my time series like this (please ignore modeling
parameters as they are not important now):
x = scan("C:/data.txt")
x = ts(x, start=1, frequency=1)
x.fit<-arima(x, order = c(1,0,0), seasonal = list(order=c(0,0,1)))
Now I want to use this model for forecasting and backtesting (!).