Displaying 20 results from an estimated 1000 matches similar to: "arima0() (PR#314)"
2011 Sep 09
2
Different results with arima in R 2.12.2 and R 2.11.1
Hello , I have estimated the following model, a sarima:
p=9
d=1
q=2
P=0
D=1
Q=1
S=12
In R 2.12.2
Call:
arima(x = xdata, order = c(p, d, q), seasonal = list(order = c(P, D, Q),
period = S),
optim.control = list(reltol = tol))
Coefficients:
ar1 ar2 ar3 ar4 ar5 ar6 ar7 ar8
ar9
0.3152 0.8762 -0.4413 0.0152 0.1500 0.0001 -0.0413 -0.1811
2011 Aug 30
2
ARMA show different result between eview and R
When I do ARMA(2,2) using one lag of LCPIH data
This is eview result
>
> *Dependent Variable: DLCPIH
> **Method: Least Squares
> **Date: 08/12/11 Time: 12:44
> **Sample (adjusted): 1970Q2 2010Q2
> **Included observations: 161 after adjustments
> **Convergence achieved after 14 iterations
> **MA Backcast: 1969Q4 1970Q1
> **
> **Variable Coefficient Std.
2013 May 02
1
warnings in ARMA with other regressor variables
Hi all,
I want to fit the following model to my data:
Y_t= a+bY_(t-1)+cY_(t-2) + Z_t +Z_(t-1) + Z_(t-2) + X_t + M_t
i.e. it is an ARMA(2,2) with some additional regressors X and M.
[Z_t's are the white noise variables]
So, I run the following code:
for (i in 1:rep) { index=sample(4,15,replace=T)
final<-do.call(rbind,lapply(index,function(i)
2001 Dec 16
3
Arima
I did a regression with ARMA errors using arima0 with
ari<-arima0(y,order=c(2,0,2),xreg=reg1,delta=-1)
or
ari<-arima0(y,order=c(2,0,2),xreg=reg1)
where reg1 is the matrix of the regressors and when I see diag(ari$var.coef)
I get negative terms. Do you know what this mean ?
I try to change transform.pars to 0 or 1 but this crash R on Windows.
Is it possible to test the significativity
2017 Jun 20
1
How to write an estimated seasonal ARIMA model from R output?
I'm trying to use the following command.
arima (x, order = c(p,d,q), seasonal =list(order=c(P,D,Q), period=s)
How can I write an estimated seasonal ARIMA model from the outputs. To be specifically, which sign to use? I know R uses a different signs from S plus.
Is it correct that the model is:
(1-ar1*B-ar2*B^2-...)(1-sar1*B^s-sar2*B^2s-....)(1-B)^d(1-B^s)^D
2002 Apr 02
1
predict with arima0
Dear R People:
I'm trying to use the predict command on an arima0 object.
I do the following:
xm.arma <- arima0(xm2,order=c(1,0,1))
predict(xm.arma,n.ahead=2)
and I get the message:
Error in round(x, digits) : Non-numeric argument to mathematical function
Any ideas what the problem might be, please?
R version 1 4 1 on Windows.
Thanks in advance!
Sincerely,
Erin Hodgess
Associate
2006 Jun 01
1
why does arima returns "NAN" standard error?
Hi everyone,
-----------------------------
Coefficients:
ar1 ar2 ma1 ma2 sar1 intercept drift
1.5283 -0.7189 -1.9971 0.9999 0.3982 0.0288 -9e-04
s.e. 0.0869 0.0835 0.0627 0.0627 0.1305 NaN NaN
sigma^2 estimated as 0.04383: log likelihood = 4.34, aic = 7.32
Warning message:
NaNs produced in: sqrt(diag(object$var.coef))
2008 Nov 20
2
Reformatting a table
Hi !
I am new to R. Can somebody help me in reformatting huge output files ,i.e, rearranging sets of columns in specific order.
For example: I have data for three compunds 1, 2 and 3
file1:
ID CA1 CA3 CA2 MA2 MA1 MA3
1 14 15 13 7 12 3
2 19 7 12 10 14 5
3 21 12 19 6 8 9
to
File 2:
ID CA1 CA2 CA3 MA1 MA2 MA3
1 14 13 15 12 7 3
2 19 12 7 14 10 5
3 21 19 12 8 6 9
or File3:
ID
2007 Aug 31
3
Choosing the optimum lag order of ARIMA model
Dear all R users,
I am really struggling to determine the most appropriate lag order of ARIMA model. My understanding is that, as for MA [q] model the auto correlation coeff vanishes after q lag, it says the MA order of a ARIMA model, and for a AR[p] model partial autocorrelation vanishes after p lags it helps to determine the AR lag. And most appropriate model choosed by this argument gives
2009 Jan 23
1
forecasting error?
Hello everybody!
I have an ARIMA model for a time series. This model was obtained through an
auto.arima function. The resulting model is a ARIMA(2,1,4)(2,0,1)[12] with
drift (my time series has monthly data). Then I perform a 12-step ahead
forecast to the cited model... so far so good... but when I look the plot of
my forecast I see that the result is really far from the behavior of my time
2009 Nov 02
2
using exists with coef from an arima fit
Dear R People:
I have the output from an arima model fit in an object xxx.
I want to verify that the ma1 coefficient is there, so I did the following:
> xxx$coef
ar1 ar2 ma1 intercept
1.3841297 -0.4985667 -0.9999996 -0.1091657
> str(xxx$coef)
Named num [1:4] 1.384 -0.499 -1 -0.109
- attr(*, "names")= chr [1:4] "ar1" "ar2"
2010 Jul 15
1
scope of an argument in a function
Hi
I am trying to define a function fu() in the following way but when I try to
run I get the error that ma1 is not found. I am not sure where I am going
wrong? Does the scope of ma1 not extend to an expr.frame object?
expr.frame() is under library tradesys.
function (y,ma1,ma2)
{
x <- y[, c("Open","Close")]
d <- expr.frame(x, list(MAf=quote(SMA(Close, ma1)),
2003 Dec 18
1
Help with predict.Arima with external regressor values [Repalced]
Hi all there
I am enjoying R since 2 weeks and I come to my first deadlock, il am trying
to use predict.Arima in the ts package.
I get a "Error in cbind(...) : cannot create a matrix from these types"
-- Start R session -----------------------------------------------------
> fitdiv <- arima(data, c(2, 0, 3), xreg = y ) ; print(fitdiv)
Call:
arima(x = data, order = c(2, 0, 3),
2011 Nov 14
1
string to list()
I can get an array of strings for the data that I want using 'paste()' as
follows:
paste('ma', 1:am$arma[2], '=', coef(am)[1:am$arma[2] + am$arma[1]], sep='')
This results in a vector of strings like:
[1] "ma1=1.17760133668255" "ma2=0.649795570407939" "ma3=0.329456750858276"
What I would like is
fixed.pars <-
2000 Sep 20
1
lag() and lm()
Hi,
I am using R interactively for estimation and even data manipulation. I want
to use lag() function within lm() function in a way looks like:
mymodel<- lm(y~x+I(lag(y,-1)-1, data=anydata)
What I get is always perfect fit; (that is, coefficient=1) which is not
true.
If the model looks like
mymodel<- lm(y~z+x+I(lag(x,-1)-1, data=anydata)
summary returns only one coefficient for x and
2003 Apr 30
2
Bug in arima?
I'm using the fixed argument in arima. Shouldn't ar4, ar5, and ar6
display as zero in the output?
Call:
arima(x = window(log(hhprice), start = c(1990, 1), end = c(2003, 3)),
order = c(7,
1, 0), xreg = window(ts.union(exa1 = lag(exa, -1), exa12 = lag(exa,
-12), exb1 = lag(exb, -1), exc1 = lag(exc, -1), exc12 = lag(exc,
-12)), start = c(1990, 1), end = c(2003, 3)),
2011 Sep 12
1
Difference in function arima estimation between 2.11.1 and R 2.12.2
Hello , I have estimated the following model, a sarima:
p=9
d=1
q=2
P=0
D=1
Q=1
S=12
In R 2.12.2
Call:
arima(x = xdata, order = c(p, d, q), seasonal = list(order = c(P, D, Q),
period = S),
optim.control = list(reltol = tol))
Coefficients:
ar1 ar2 ar3 ar4 ar5 ar6 ar7 ar8
ar9
0.3152 0.8762 -0.4413 0.0152 0.1500 0.0001 -0.0413 -0.1811
2002 Nov 09
2
importing data from Excel using RODBC
Hi,
I used RODBC to import data from an Excel spreadsheet "*.xls", but some
columns were returned as zeros. When I looked at these columns in Excel, I
found that thery are results of formula calculations and not entry. My
question is: Is there any parameter or command I need to use in order to
overcome this problem?
Thank you
Ahmad Abu Hammour
2001 Apr 12
1
estimates for e in procedure arima0() ?
Dear all,
this may be a stupid question but...
The underlying model in procedure arima0 is
X[t] = a[1]X[t-1] + ... + a[p]X[t-p] + e[t] + b[1]e[t-1] + ... +b[q]e[t-q]
Is it possible to get an estimate of e for every point t, t-1 etc. or
at least an estimate of the variance of e?
Thanks a lot in advance for any hints
Kai Arzheimer