Displaying 20 results from an estimated 3000 matches similar to: "fGarch: how to use garchFit() in loop?"
2008 Apr 01
1
garch prediction
Hello
I want to predict the future values of time series with Garch
When I specified my model like this:
library(fGarch)
ret <- diff(log(x))*100
fit = garchFit(~arma(1,0,0)+garch(1, 1), data =ret)
predict(fit, n.ahead = 10)
meanForecast meanError standardDeviation
1 0.01371299 0.03086350 0.03305819
2 0.01211893 0.03094519 0.03350248
2011 Sep 28
1
fGarch - Fitting and APARCH-Modell with fixed delta
Hi there,
I'm trying to fit a GJR-GARCH Model using fGarch. I wanted to try that by
fitting an APARCH model with a fixed delta of 2 and a non-fixed gamma. So I
was simply trying to use:
spec <- garchFit(~aparch(1,1),data=garchSim(),delta=2)
coef(spec)
And sometimes, it's working like a charm and delta is indeed exactly 2 in
the resulting coefficient vector.
Frequently, though, the
2009 Mar 02
1
(no subject)
Greetings,
I am using fGarch package to estimate and simulate GARCH models. What I would like to do is to perform Monte Carlo simulation. Unfortunately I cannot figure how to modify the code to achieve this. I use the following code to run a single simulation:
spec=garchSpec(model=list(ar= 0.440270860, omega=0.000374365,alpha=0.475446583 , mu=0, beta=0))
sim<-garchSim(spec,
2004 Nov 10
2
fSeries
Good morning everyone,
I use for the first time the package fSeries and i try to run the example
given by Diethelm Würtz. But when i run its example which is the following
#
# Example:
# Model a GARCH time series process
#
# Description:
# PART I: Estimate GARCH models of the following type ARCH(2)
# and GARCH(1,1) with normal conditional distribution functions.
# PART II: Simulate
2008 Dec 30
1
A mistake in garchFit()? {fGarch}
Hello,
I was using garchFit {fGarch} to fit some GARCH processes.
I noticed that the result contains "Log Likelihood" value (right above
"Description"), but when I use .. at fit$llh to retrieve Log Likelihood value,
the sign switched.
I am confused about which value I should choose to report...
Any help here?
Thanks a lot!
Ted
--
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2012 Oct 11
1
a question
Dear R-helpers,
I need to read some data from output of garchFit in fGarch.
my model is garch(1,1) and i want to read
coefficients(omega,alpha,beta) and timeseries(x) and conditional
SD(s). because i need them to use in other formula.
for example :omega+x[1]+s[3]
and maybe i have several simulation then i need a general way to read
them, not to read with my eyes for example the quantity of
2009 Apr 06
1
Problem with Extracting Fitted Values from fGarch package
Good day everyone,
I fitted a GARCH model to a time series and R estimated the model and provide me with the estimates. However, when I tried to extract the fitted values from the estimated model I got the following error message:
"Error in .local(object, ...) : object "fit" not found"
I used the following to extract the fitted values
fitted_TASI <- fitted(garchFit(~
2006 May 08
3
GARCH SIMULATION
Hi All,
I,m trying to do a GARCH simulation in R 2.3.0 release
in Windows XP. I've seen garchsim function but that is
for garch (1,1) and ?garch gives an example for ARCH
simulation. Can anyone help me how can i extend the
help shown in ?garch to GARCH simulation? Please help
me in this regard.
Thanks,
Sumanta Basak.
2011 May 04
1
fGarch
Hi,
I am attempting to fit a ARMA/GARCH regression model without success.
### ARIMA-GARCH model with regressor ###
### Time series data: A multivariate data set.
cov.ts.dq = cov.ts[1:4,"dq1"][!is.na(cov.ts[,"dq1"])]
cov.ts.day = ts.intersect(dq = diff(q.ts), day = lag(q.ts, -1))
### The following R scripts work:
(summary(no.day.fitr <- garchFit(dq ~ arma(0,3) +
2009 Jun 19
1
using garchFit() to fit ARMA+GARCH model with exogeneous variables
Hello -
Here's what I'm trying to do. I want to fit a time series y with
ARMA(1,1) + GARCH(1,1), there are also an exogeneous variable x which I
wish to include, so the whole equation looks like:
y_t - \phi y_{t-1} = \sigma_t \epsilon_t + \theta \sigma_{t-1}
\epsilon_{t-1} + c x_t where \epsilon_t are i.i.d. random
variables
\sigma_t^2 = omega + \alpha \sigma_{t-1}^2 + \beta
2011 Mar 24
1
Problems with predict in fGarch
Hello. I am using fGarch to estimate the following model:
Call:
garchFit(formula = fmla, data = X[, i], trace = F)
Mean and Variance Equation:
data ~ arma(1, 1) + garch(1, 1)
Conditional Distribution:
norm
Coefficient(s):
mu ar1 ma1 omega alpha1 beta1
-0.94934 1.00000 -0.23211 54.06402 0.45709 0.61738
Std. Errors:
based on Hessian
Error Analysis:
2009 Jun 30
1
garchFit in fGarch fitted values are all the same
Dear all-
Package /fGarch/ version 2100.78 in R version 2.8.1 (2008-12-22)
running on linux 2.6.22.9-91.fc7
In trying to fit garch models in above environment. I am getting
"reasonable" fitted coefficients, but the fitObject@fitted are all the
same. This is true even for the help page example:
library(fGarch)
R> X.timeSeries = as.timeSeries(msft.dat)
R> head(
+
2009 Mar 03
0
Monte carlo simulation in fGARCH
I use fGarch package to estimate AR(1)-ARCH(1) process for a vector of returns. Then, using the estimated parameters I want to simulate 10 000 sample paths where each path has the same length as the vector of returns. So the first line of the code is: spec=garchSpec(model=list(ar= 0.440270860, omega=0.000374365,alpha=0.475446583 , mu=0, beta=0))----
The only way I can think of generating 10 000
2007 Jul 19
1
Questions regarding R and fitting GARCH models
Dear all,
I've recently switched from EViews to R with RMetrics/fSeries (newest
version of july 10) for my analysis because of the much bigger
flexibility it offers. So far my experiences had been great -prior I
had already worked extensively with S-Plus so was already kind of
familiar with the language- until I got to the fSeries package.
My problem with the documentation of fSeries is that
2008 Aug 18
1
another GARCH problem
Hallo,
i want to fit a GARCH model with a extern regressor (without arma
components), so i found the following function in package fGarch. I tryed
out a lot of things but usually I get this Error.
> garchFit(formula=y~x, formula.var=~garch(1,1),data=w)
Error in .garchFit(formula.mean, formula.var, series = x, init.rec, delta,
:
Algorithm only supported for mci Recursion
I think i use the
2011 May 15
4
DCC-GARCH model
Hello,
I have a few questions concerning the DCC-GARCH model and its programming in
R.
So here is what I want to do:
I take quotes of two indices - S&P500 and DJ. And the aim is to estimate
coefficients of the DCC-GARCH model for them. This is how I do it:
library(tseries)
p1 = get.hist.quote(instrument = "^gspc",start = "2005-01-07",end =
2009 Apr 29
1
arma model with garch errors
Dear R experts,
I am trying to estimate an ARMA 2,2 model with garch errors.
I used the following code on R 2.9.
#library
library(fGarch)
#data
data1<-ts(read.table("C:/Users/falcon/Desktop/Time
Series/exports/goods1.csv"), start=c(1992,1), frequency=12)
head(data1)
#garch
garchFit(formula.mean= ~arma(2,2),formula.var=~garch(1,1), data=data1)
but get this error:
>
2011 May 12
2
DCC-GARCH model and AR(1)-GARCH(1,1) regression model
Hello,
I have a rather complex problem... I will have to explain everything in
detail because I cannot solve it by myself...i just ran out of ideas. So
here is what I want to do:
I take quotes of two indices - S&P500 and DJ. And my first aim is to
estimate coefficients of the DCC-GARCH model for them. This is how I do it:
library(tseries)
p1 = get.hist.quote(instrument =
2008 May 23
1
GARCH-like
I need to change the code of Garch to the FCGARCH (a non-linear
multi-regime GARCH).
I don't know nothing about R.
I'd like to know how can I get the code of the garch in order to change it
and make the fit for the FC-GARCH.
Any non-linear code will be helpfull because if doesn't help in the
programming it helps in getting familiar with R.
Thank you
Renato
--
PhD Student Renato
2010 Jul 14
0
fGarch: garchFit() with fixed coefficents
hello everybody,
I would like to fit a model to a times series (testing set) for out of
sample predictions using garchFit(). I would like to keep the coefficients
of ARMA/GARCH model fixed (as found by fitting the model to my training
set). The arima fitting function has such an option for that (fixed=NULL)
but the garchFit() doesnt.
It is very important for me to keep the same coefficients