Displaying 20 results from an estimated 800 matches similar to: "Simple AR(2)"
1999 Jul 19
9
time series in R
Time Series functions in R
==========================
I think a good basic S-like functionality for library(ts) in base R
would include
ts class, tsp, is.ts, as.ts
plot methods
start end window frequency cycle deltat
lag diff aggregate
filter
spectrum, spec.pgram, spec.taper, cumulative periodogram, spec.ar?
ar -- at least univariate by Yule-Walker
arima -- sim, filter, mle, diag, forecast
2010 Dec 08
1
Newbie - want to view code for a function
Brand new to R
Want to understand the algorithm used in yule-walker time series
autoregression model
I assume there is a way to see the source for ar.yw
I also assume that everybody except me knows how
Could someone suggest to me how to find out
I've looked thru some of the documenttion - there's a lot - and
apparently I haven't looked the right place.
Thanks in advance
Dick
2009 Nov 13
2
AR(2) modelling
Hi useRs,
I'm trying to fit a basic AR(2) model with the 'ar' function. And when
I try to check the value of the coefficients, I could not find the
same value as the 'ar' function.
Here is my example:
myserie <- c(212, 205, 210, 213, 217, 222, 216, 218, 220, 212, 215, 236)
#plot(myserie, type="l")
myserieminus0 <- tail(myserie, -2)
myserieminus1 <-
2009 Nov 13
2
AR(2) modelling
Hi useRs,
I'm trying to fit a basic AR(2) model with the 'ar' function. And when
I try to check the value of the coefficients, I could not find the
same value as the 'ar' function.
Here is my example:
myserie <- c(212, 205, 210, 213, 217, 222, 216, 218, 220, 212, 215, 236)
#plot(myserie, type="l")
myserieminus0 <- tail(myserie, -2)
myserieminus1 <-
2000 Jun 20
1
pacf
Dear list,
according to the documentation of acf{ts}
"the partial correlation coefficient is estimated by fitting
autoregressive models of successively higher orders up to lag.max. "
However, R seems to return the Yule-Walker estimates of the PACF by
default. You can check this using c(1:10) as the series: the YW
estimates are 0.7000000 and -0.1527035 for lags 1 and 2 . If the PACF
2007 Nov 23
4
help pleaseeeeeeeee
Dears Sirs
During my computational work I encountered unexpected behavior when calling
"ar" function, namely
# time series
x<-ts(c(-0.2052083,-0.3764986,-0.3762448,0.3740089,0.2737568,2.8235722,-
1.7783313,0.2728676,-0.3273164),start=c(1978,3),frequency=4,end=c(1980,3))
# ar function
res.ar<-ar(x,aic=TRUE,demean=F)
# call "ar" again and ............
2007 Nov 27
1
help in ar function
Dears Sirs
During my computational work I encountered unexpected behaviour when calling "ar" function.
I want to select the order p of the autoregressive approximation by AIC criterion and sometimes an error occurs.
Example:
# time series
2012 Feb 10
3
Help needed please
I have coded a time series from simulated data:
simtimeseries <- arima.sim(n=1024,list(order=c(4,0,0),ar=c(2.7607, -3.8106, 2.6535, -0.9258),sd=sqrt(1)))
#show roots are outside unit circle
plot.ts(simtimeseries, xlab="", ylab="", main="Time Series of Simulated Data")
# Yule ----------------------------------------------------------------------------
q1 <-
2012 Feb 07
1
fixed effects with clustered standard errors
Dear R-helpers,
I have a very simple question and I really hope that someone could help me
I would like to estimate a simple fixed effect regression model with clustered standard errors by individuals.
For those using Stata, the counterpart would be xtreg with the "fe" option, or areg with the "absorb" option and in both case the clustering is achieved with "vce(cluster
2006 Dec 05
1
Cannot connect to Samba-3.0.23d (and earlier) from other trusted AD domains
Hi there
We have a bunch of Samba 3.0.10+ CentOS4.4 servers that are working 100%
fine when connected to from users who are members of the same ADS domain
our Samba servers are members of. However, users from other ADS domains
(we are all W2K3-based) on our network cannot connect - they get
NT_STATUS_ACCESS_DENIED. The shares they are trying to connect to have
no share-level permission checks -
2006 Mar 15
1
(newbie) Weighted qqplot?
Folks,
Normally, in a data frame, one observation counts as one observation
of the distribution. Thus one can easily produce a CDF and (in Splus
atleast) use cdf.compare to compare the CDF (BTW: what is the R
equivalent of the SPlus cdf.compare() function, if any?)
However, if each point should not count equally, how can I weight the
points before comparing the distributions? I was thinking of
2009 Jun 02
1
plot 4th variable contour lines on filled.contour
Hello,
I have a dataset with 4 variables, each consisting of a vector, all with
the same length. I start by interpolating the first three variables
using the function "interp", and plot the interpolation successfully
using "filled.contour". I then interpolate the first two variables and a
fourth using "interp" again, but when I try to overlay the contour
lines
2007 Nov 24
1
Bug in package stats function ar() (PR#10459)
Full_Name: Steven McKinney
Version: 2.6.0
OS: OS X
Submission from: (NULL) (142.103.207.10)
Function ar() in package "stats" is showing
a quirky bug. Some calls to ar() run to
completion, others throw an error.
The bug is reproducible by several people on different
machines, however, the ar() function itself ends
up throwing the error sporadically. Several calls to
ar() may be
2005 Nov 28
3
How Can I change the acf's plot type?
In the R Document, the usage of the acf() is as follow:
acf(x, lag.max = NULL,
type = c("correlation", "covariance", "partial"),
plot = TRUE, na.action = na.fail, demean = TRUE, ...)
But now I want to get the result picture like:
plot(x,type="l")
or
plot(x,type="p")
How can I do this with acf function?
仭仭仭仭仭仭仭仭仭仭仭仭仭仭仭仭佒伮
伬侎仯仭
2003 Dec 15
2
Week of the Year date conversion
Hello there fellow R-users,
I have received some data which comes in the following format:
example1<-"200301"
The first 4 digits correspond to the year and the remaining 2 digits
correspond to the week of the year.
I have tried to convert this to a date by using strptime as follows:
strptime(example1,format="%Y%U")
where U (looking up strptime) is the week of the
2004 Jan 22
1
spectrum
Dear R users
I have two questions about estimating the spectral power of a
time series:
1) I came across a funny thing with the following code:
data(co2)
par(mfrow=c(2,1))
co2.sp1<-spectrum(co2,detrend=T,demean=T,span=3)
co2.sp2<-spectrum(co2[1:468],detrend=T,demean=T,span=3)
The first plot displays the frequencies ranging from 0 to 6
whearas the second plot displays the same curve but
2007 Aug 01
4
profiles?
Sometimes a user logging in takes a while. I suspect the
time delay is due to the size of a user's profile. Where
is the profile data kept and how can this data be scrubbed
or compressed?
Mike
2012 Feb 07
1
fixed effects linear model in R
Dear R-helpers,
First of all, sorry for those who have (eventually) already received that request.
The mail has been bumped several times, so I am not sure the list has received it... and I need help (if you have time)! ;-)
I have a very simple question and I really hope that someone could help me
I would like to estimate a simple fixed effect regression model with clustered standard errors by
2006 Nov 13
1
bug in acf (PR#9360)
Full_Name: Ian McLeod
Version: 2.3.1
OS: Windows
Submission from: (NULL) (129.100.76.136)
> There is a simple bug in acf as shown below:
>
> z <- 1
> acf(z,lag.max=1,plot=FALSE)
> Error in acf(z, lag.max = 1, plot = FALSE) :
> 'lag.max' must be at least 1
>
This is certainly a bug.
There are two problems:
(i) the error message is wrong since lag.max is
2024 Feb 23
2
help - Package: stats - function ar.ols
Hello,
Thanks for the reply Rui and for pointing out that I forgot to attach
my code. Please find attached in this email my code and data.
Thanks in advance.
Best regards, Pedro Gerhardt Gavronski.
On Fri, Feb 23, 2024 at 5:50?AM Rui Barradas <ruipbarradas at sapo.pt> wrote:
>
> ?s 16:34 de 22/02/2024, Pedro Gavronski. escreveu:
> > Hello,
> >
> > My name is Pedro