Displaying 20 results from an estimated 1000 matches similar to: "using exists with coef from an arima fit"
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
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
2012 Apr 26
1
Using the R predict function to forecast a model fit with auto.arima function
Hello R users,
Hope everyone is doing great.
I have a dataset that is in .csv format and consists of two columns: one
named Period (which contains dates in the format yyyy_mm) and goes from
1995_10 to 2007_09 and the second column named pcumsdry which is a
volumetric measure and has been formatted as numeric without any commas or
decimals.
I imported the dataset as pauldataset and made use of
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.
2006 Nov 23
1
ARMAX Models in R
Hi,
I want to model different timeseries with ARMAX models in R because I think
that ARMAX models will map best to these data.
Besides I don't want to use the order of the AR or MA part but the lag e.g.
AR Part =ar1, ar2, ar7; MA Part =ma1, ma3 and I want to use exogenous
variables as well.
I coudn't find any solutions in the R help and therefore I want to ask all
of you.
Does anyone
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))
2012 May 04
1
Problems Exporting R Output to an xls file need help
Hello R users,
I want to export to an xls or .csv some predictions I produced with the
auto.arima and forecast functions.
A detail of all my work is presented below. I loaded a package called
dataframes2xls and tried to use the function write.xls without any success.
Can anybody help me figure this out? How could I get R to export the output
to an xls file?
Any help will be greatly
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
2007 Jan 30
5
how to join two arrays using their column names intersection
Dear all,
I have a problem that may be someone of you can help. I am a newbie and
do not find how to do it in manuals.
I have two arrays, for example:
ar1 <- array(data=c(1:16),dim=c(4,4))
ar2 <- array(data=c(1:16),dim=c(4,4))
colnames(ar1)<-c("A","B","D","E")
colnames(ar2)<-c("C","A","E","B")
> ar1
2001 Sep 26
1
Table help
Hi,
A quick question:
I have to vectors, say ar1 and ar2
> ar1
[1] "a" "c" "c" "a"
attr(,"levels")
[1] "a" "b" "c"
> ar2
[1] TRUE TRUE FALSE TRUE
> table(ar1, ar2)
ar2
ar1 FALSE TRUE
a 0 2
c 1 1
I would like to obtain:
T F
a 2 0
b 0 0
c 1 1
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
1999 Nov 07
2
arima0() (PR#314)
Full_Name: Ahmad Abu Hammour
Version: rw0651
OS: windows 95
Submission from: (NULL) (63.23.128.44)
Although I know that "ts package" is preliminary, I wanted to compare the
results from R and SPSS. I ran ARIMA(2,1,2) in both softwares. I got NaN in
standard errors of coefficients from R and real figures from SPSS. I changed
"delta" in R to match that used by SPSS, I received
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)
2010 Nov 22
2
Help: Standard errors arima
Hello,
I'm an R newbie. I've tried to search, but my search skills don't seem
up to finding what I need. (Maybe I don't know the correct terms?)
I need the standard errors and not the confidence intervals from an
ARIMA fit.
I can get fits:
> coef(test)
ar1 ma1
intercept time(TempVector) - 1900
2009 Feb 03
3
Problem about SARMA model forcasting
Hello, Guys:
I'm from China, my English is poor and I'm new to R. The first message I sent to R help meets some problems, so I send again.
Hope that I can get useful suggestions from you warm-hearted guys.
Thanks.
I builded a multiplicative seasonal ARMA model to a series named "cDownRange".
And the order is (1,1)*(0,1)45
The regular AR=1; regular MA=1; seasonal AR=0; seasonal
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),
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)),
2023 Jan 05
1
R 'arima' discrepancies
Rob J Hyndman gives great explanation here
(https://robjhyndman.com/hyndsight/estimation/) for reasons why results
from R's arima may differ from other softwares.
@iacobus, to cite one, 'Major discrepancies between R and Stata for
ARIMA'
(https://stackoverflow.com/questions/22443395/major-discrepancies-between-r-and-stata-for-arima),
assign the, sometimes, big diferences from R
2007 Apr 26
1
comparing two matrices, row by row
Estimated people,
I have two matrices:
ar1 <- array(data=c(1:16),dim=c(4,4))
ar2 <- array(data=c(1,2,3,3,5:16),dim=c(4,4))
They only differ in the fourth row. I would like to compare them in order to know which columns are equal.
The following works, but I would like to have a better solution, and not to use what someone called "prehistorical loops":
for(i in
2011 Mar 02
1
Refine ARMA model
Dear users,
I tried to fit an AR(2) model to data. This the result:
> arima(vw,c(3,0,0))
Call:
arima(x = vw, order = c(3, 0, 0))
Coefficients:
ar1 ar2 ar3 intercept
0.1052 -0.0102 -0.1203 0.0099
s.e. 0.0337 0.0339 0.0338 0.0018
sigma^2 estimated as 0.002934: log likelihood = 1293.16, aic = -2576.33
Now, ar2 is not significantly different from