Displaying 20 results from an estimated 5000 matches similar to: "for help"
2010 Mar 17
1
Reg GARCH+ARIMA
Hi,
Although my doubt is pretty,as i m not from stats background i am not sure
how to proceed on this.
Currently i am doing a forecasting.I used ARIMA to forecast and time series
was volatile i used garchFit for residuals.
How to use the output of Garch to correct the forecasted values from ARIMA.
Here is my code:
###delta is the data
fit<-arima(delta,order=c(2,,0,1))
fit.res <-
2008 Sep 19
1
Cbind help
Hi there
I want to cbind a vector(contains 20 values) to a dataframe containg (18
rows).The missing value in the dataframe is however a repeated values but
still i want to retain the repeats in the vector and the dataframe values
can even get enterd twice.
how should i go about it
Example:
Vector(contains repeating entry)
ab de dc ab be
dataframe(unique entry)
ab a b c d e
dc e f g h i
de l
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(
+
2011 May 10
0
DCC-GARCH model and AR(1)-GARCH(1, 1) regression model - help needed..
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 =
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) +
2012 Mar 11
0
specify GARCH model, using garchFit()
Hello,
I’ve fitted a Garch(2,1) model with function 'garchFit()' from the package
'fGarch':
> m1 <- garchFit(formula = ~garch(2,1),data = X,trace = F)
* See 'summary(m1)' OUTPUT BELOW *
PROBLEM: My alpha1 term is not significant and I would like to make a NEW
model, say m2, that does not contain alpha1, but I am not sure how to
specify this with the garchFit()
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 =
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:
>
2008 Mar 24
0
ARCH(1,0) with t-residuals
Dear R users,
I need to estimate an ARCH(1,0) model with t-residuals. To do this I use garchFit
function from fGarch library. However, I get the following error message:
Error in.garchInitParameters (formula.mean = formula.mean, formula.var =
formula.var, ): object "alpha" not found
I tried to estimate this model with different series, but I always get this error message.
For example,
2011 Nov 20
1
alpha_1 + beta_1 >1 in GARCH(1,1)
Hi,
as i suppose to know in a stationary GARCH(1,1) model the sum of alpha and
beta has to be smaller than 1.
But if i use the garchfit() function from the package fGarch for my
timeseries the sum is bigger than 1.
The adf.test tells me a p-value smaller than 0.01 instead.
What does this mean for me?
Can i trust in the coefficients in this case?
mfg user84
--
View this message in context:
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
2006 Nov 22
0
questions about garchFit
Hi all,
I was trying garchFIt() of fSeries to fit volatility of monthly log returns
of S&P500. I tried residuals of normal, student t, skew normal, skew t. But
all innovations except normal got exaxtly same coefficients, even if I
changed their parameters of skew and shape.
Is this correct for the data or something wrong? I am attaching the code,
thank you.
Muster
#GARCH analysis of
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
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
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
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 =
2006 Nov 22
2
problems with garchFit
Hi all,
I post it on both r-help and r-finance since I don't know where is most
appropriate for this topic. Sorry if it bothers you.
I did garch fitting on S&P500 monthly returns with garchFit from fSeries. I
got same coefficients from all cond.dist except normal. I thought that is
probabaly usual for the data. But when I play with it, I got another
question.
I plot skew normal with
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
2006 May 19
0
how to estimate adding-regression GARCH Model
---------- Forwarded message ----------
From: ma yuchao <ma.yuchao@gmail.com>
Date: 2006-5-20 ÉÏÎç4:01
Subject: hello, everyone
To: R-help@stat.math.ethz.ch
Hello, R people:
I have a question in using fSeries package--the funciton garchFit and
garchOxFit
if adding a regression to the mean formula, how to estimate the model in
R? using garchFit or garchOxFit?
For example,
2007 Jul 19
0
fSeries GARCH(1,1)
Hello all, I am trying to use the "garchFit" function in the fSeries Package
to fit a Garch(1,1) Model with t distribution. I am using the following
codes.
fit <- garchFit(~garch(1,1),data,cond.dist="dstd")
fitted(fit)
I was expecting the fitted(fit) would return the fitted volatility, but the
result turns out to be a series of repeated same value. I tried to change
the