Displaying 20 results from an estimated 7000 matches similar to: "Use of hosking.sim R function"
2009 Apr 05
0
Question about arima.sim()
Hi,
I tried to simulate an ARIMA model by using arima.sim(), say arima.sim(n=100,list(order=c(1,0,1),ar=0.6,ma=0.9,sd=1), but the acf and pacf of simulated data using acf() and pacf() are so much different from the theoritcal acf and pacf. For instance, in my case, ar=0.6 and ma=0.9, so the acf for all lags should be greater than 0 based on the theoritical calculation, but the acf of simulated
2002 Feb 13
0
L-moments/Hosking & Wallis (1997)
1) L-moments:
Does anyone know of any R code that will calculate these? (I'm aware that
these can be calculated in S-Plus using the EnvironmentalStats for S-Plus
module.)
2) Hosking & Wallis (1997): "Regional frequency analysis: an approach based
on L-moments"
Does anyone know of any code in either R or S-plus that implements the
discordancy and homogeneity methods described
2005 Dec 23
1
dse package problems
I am having problems with the package dse. I just installed R 2.2.1
and reinstalled all packages. I am running Windows XP Pro with all
updates.
Below there are two examples of error messages generated when trying
to execute some simple programs. The code was taken directly from the
package documentation.
Any help on this will be greatly appreciated.
Merry Christmas
Fernando
2003 Nov 21
0
gls with serial correlation
Hello there fellow R users,
Im trying to fit a gls model to data which has serial correlation in the
errors e(t)=p*e(t-1).
However I dont seem to be having much luck in erradicating the
autocorrelation in the residuals.
I have created the following example.
library(nlme)
x<-rnorm(100)
y<-3+2*x
y<-y+arima.sim(100,model=list(ar=(0.6)))+rnorm(100,0,0.2)
#Create a data set with first
2008 Sep 21
1
card reader "sim-max"
hi!
some time ago i have purchased card reader for scanning sim-card.
it have usb inerface.
in set was cd with soft (as usual only for windows)
soft on cd:
usb-driver installer
sim max 5.16
& i try to run it on mandriva2008 kernel 2.6.22.9
first i try to install 'usb-driver installer.exe'
then install sim max 5.16(it's 2 prog.: sim editor and sim scanner),but that's wrong
way!
2010 Aug 19
1
How to include trend (drift term) in arima.sim
I have been trying to simulate from a time series with trend but I don't see
how to include the trend in the arima.sim() call. The following code
illustrates the problem:
# Begin demonstration program
x <- c(0.168766559, 0.186874000, 0.156710548, 0.151809531, 0.144638812,
0.142106888, 0.140961714, 0.134054659, 0.138722419, 0.134037018,
0.122829846, 0.120188714,
2004 May 24
1
Null model for arima.sim().
In some time series simulations I'm doing, I occasionally want the
model to be ``white noise'', i.e. no model at all. I thought it
would be nice if I could fit this into the arima.sim() context,
without making an exceptional case. I.e. one ***could*** do
something to the effect
if(length(model)==0) x <- rnorm(n) else x <- arima.sim(model,n)
but it would be more suave if one
1999 Nov 14
1
bug in arma.sim (PR#322)
Dear Sir,
I think I found a bug in the function arma.sim, which is defined in
the help page of the function filter:
arma.sim <- function(n, ar = NULL, ma = NULL, sigma = 1.0)
{
x <- ts(rnorm(n+100, 0, sigma^2), start = -99)
if(length(ma)) x <- filter(x, ma, sides=1)
if(length(ar)) x <- filter(x, ar, method="recursive")
as.ts(x[-(1:100)])
}
I am using R
2005 Oct 10
1
using innov in arima.sim
Hello,
I have used the arima.sim function to generate a lot of time series, but to day I got som results that I didn't quite understand. Generating two time series z0 and z1 as
eps <- rnorm(n, sd=0.03)
z0 <- arima.sim(list(ar=c(0.9)), n=n, innov=eps)
and
z1 <- arima.sim(list(ar=c(0.9)), n=n, sd=0.03),
I would expect z0 and z1 to be qualitatively similar. However, with n=10 the
2005 Sep 13
1
Limiting call minutes on a GSM SIM
Hi!
I'm considering to buy a GSM bridge to save on GSM calls. Right now they
are offering subscriptions with 200 minutes each month for almost nothing,
however the 400 minutes subscriptions are considerably more expensive.
Most GSM bridges can cater for 2 SIM cards, is there a way for Asterisk to
run the first SIM card to it's max and then switch to the second? (If one
call would
2009 Jan 20
0
arima.sim help
I am trying to simulate time series data for an ar(1) and ma(1) process. I want the error term to have either a t distribution with 1 degree of freedom or a normal distribution with mean=0 and sd=1. Here is my code:
error.model=function(n){rnorm(n,mean=0, sd=1)}
data<-arima.sim(model=list(ar=c(0.1)), n=1000,
n.start=200, start.innov=rnorm(200,mean=0, sd=1),
rand.gen=error.model )
data
2005 Oct 02
2
arima.sim bug?
Hi,
I am using the arima.sim function to generate some AR time series. However, the function does not seem to produce exactly the same time series when I specify the innov parameter. For example
> r <- rnorm(300)
> x <- arima.sim(300, model=list(order=c(1,0,0),ar=c(.96)), innov=r, n.start=10)
> y <- arima.sim(300, model=list(order=c(1,0,0),ar=c(.96)), innov=r, n.start=10)
>
2011 Nov 22
1
arima.sim: innov querry
Apologies for thickness - I'm sure that this operates as documented and with good reason. However...
My understanding of arima.sim() is obviously imperfect. In the example below I assume that x1 and x2 are similar white noise processes with a mean of 5 and a standard deviation of 1. I thought x3 should be an AR1 process but still have a mean of 5 and a sd of 1. Why does x3 have a mean of ~7?
2003 Jul 16
1
arima.sim problems (PR#3495)
Full_Name: Gang Liang
Version: 1.7.1
OS: Debian/Woody
Submission from: (NULL) (192.6.19.190)
> print(arima.sim(list(ar=.3,order=c(1,1,1)), 30))
[1] 0.00000000 0.10734243 0.02907301 -1.23441659 -0.98819317 -2.82731975
[7] -2.69052512 -4.22884756 -5.02820635 -5.41514613 -6.20486350 -7.01040649
[13] -6.78121289 -5.41111810 -4.96338053 -5.42395408 -6.22741444 -5.75228153
[19] -6.07346580
2009 Jul 21
0
Specifying initial values for arima.sim
Hi Everyone,
I'm having a problem with arima.sim. Namely specifying inital values
for the series.
If I generate a random walk
> vs = rnorm(100,0,1)
> xs = cumsum(vs)
and fit an ARIMA(1,0,0) to it
> xarima = arima(xs,order=c(1,0,0))
> xarima
Call:
arima(x = xs, order = c(1, 0, 0))
Coefficients:
ar1 intercept
0.9895 8.6341
s.e. 0.0106 6.1869
I should
2009 Sep 29
0
Incoherence between arima.sim and auto.arima
Hello,
I have a question about function arima.sim
I tried to somulate a AR(1) process, with no innovation, no error term.
I used this code:
library(forecast)
e=rnorm(100,mean=0,sd=0)
series=arima.sim(model=list(ar=0.75),n=100,innov=e)+20
Then I tried to applicate ti this series auto.arima function:
mod1<-auto.arima(series,stepwise=FALSE,trace=TRUE,ic='aicc')
The best model returned
2008 Jan 14
7
GSM SIM Cards and Digium, or GSM SIM Adaptor
Hi List;
Is there an Digium cards support GSM SIM cards so we
can fix an SIM card to be used for calls within
mobiles as it is less rate?
Or I have to use an FXS to SIM adaptor? If yes, then
anyone advise a models and prices?
Regards
Bilal
____________________________________________________________________________________
Be a better friend, newshound, and
know-it-all with Yahoo!
2012 Oct 08
1
arima.sim
Hi,
I have been using arima.sim from the stats package recently, and I'm
wondering why I get different results when using what seem to be the
same parameters. For example, I've given examples of three different
ways to run arima.sim with what I believe are the same parameters.
It's my understanding from the R documentation that rnorm is the
default function for rand.gen if not
2008 Jul 12
1
Help with arima.sim
Hey,
as a bloddy beginner in R I want to simulate a Arima (2,1,0) process with R.
My problem is, that I don't know how to specify the AR.
For a ARIMA(1,1,0) I use the following syntax: S <-
arima.sim(list(order=c(1,1,0), ar=0.9), n=100).
I think it is a stupid question with an easy answer. But when I google
the only results are arima.sim for an ARIMA (1,1,0).
Regards,
Chris
--
2014 Aug 07
1
Is it possible to set asterisk's VoIP authentication to be based on EAP-SIM auth of freeradius?
Hi all,
I want to make initial VoIP authentication process from asterisk server to
be based on EAP-SIM authentication of Freeradius server (so it will be not
necessary to insert account datas in the asterisk database). Is there any
way of doing that from Freeradius and Asterisk? Or at least, is there any
way to sync the EAP-SIM data on Freeradius to asterisk server?
thank you
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