similar to: arima function fix the coefficients

Displaying 20 results from an estimated 40000 matches similar to: "arima function fix the coefficients"

2009 Jun 04
2
Import ARIMA coefficients
Hello, I need to know how to import ARIMA coefficients. I already determined the coefficients of the model with other software, but now i need to do the forecast in R. For Example: I have a time series named x and i have fitted an ARIMA(1,0,1) (with other software) AR coef = -.172295 MA coef = .960043 (i know that this is not a good model, it's just an example) I try to
2011 Jul 07
3
AR vs ARIMA question
Dear R People: Here is some output from AR and ARIMA functions: > xb <- arima.sim(n=120,model=list(ar=0.85)) > xb.ar <- ar(xb) > xb.ar Call: ar(x = xb) Coefficients: 1 0.6642 Order selected 1 sigma^2 estimated as 1.094 > xb.arima <- arima(xb,order=c(1,0,0),include.mean=FALSE) > xb.arima Call: arima(x = xb, order = c(1, 0, 0), include.mean = FALSE)
2004 May 02
1
arima problems when using argument fixed=
As I am reading ?arima, only NA entries in the argument fixed= imports. The following seems to indicate otherwise: x <- arima.sim(model=list(ar=0.8), n=100) + (1:100)/50 > t <- 1:100 > mod1 <- lm(x ~ t) > > init1 <- c(0, coef(mod1)[2]) > fixed1 <- c(as.numeric(NA), 0) > > arima(x, order=c(1,0,0), xreg=t, include.mean=FALSE, init=init1, fixed=fixed1)
2009 Jun 05
1
Bug in print.Arima and patch
Dear List, A posting to R-Help exposed this problem with the print method for objects of class Arima: > set.seed(1) > x <- arima.sim(n = 100, list(ar = 0.8897, ma = -0.2279)) > mod <- arima(x, order = c(1,0,1)) > coefs <- coef(mod) > mod2 <- arima(x, order = c(1,0,1), fixed = coefs) > mod2 Call: arima(x = x, order = c(1, 0, 1), fixed = coefs) Coefficients: Error
2005 Oct 13
1
arima: warning when fixing MA parameters.
I am puzzled by the warning message in the output below. It appears whether or not I fit the seasonal term (but the precise point of doing this was to fit what is effectively a second seasonal term). Is there some deep reason why AR parameters ("Warning message: some AR parameters were fixed: ...") should somehow intrude into the fitting of a model that has only MA terms? >
2004 Jan 14
2
Fixed parameters in an AR (or arima) model
Hello I want to fit an AR model were two of the coefficients are fixed to zero (the second and third ar-coefficients). I used the "arima" function with the "fixed" argument but the ar3 coefficient is not set to zero: ============================================== > arima(Y, order=c(4,0,0), xreg=1:23, fixed=c(NA,0,0,NA,NA,NA)) Call: arima(x = Y, order = c(4, 0, 0), xreg =
2008 Sep 10
0
MA coefficients
Hi everyone, I am performing the time series regression analysis on a series of data sets. A few data sets followed an ARMA(1,1) process. However, they all had a same value of moving average MA coefficients = -1, constantly, from output of function “arima" . Example: > arima(residuals, order=c(1,0,1)) Call: arima(residuals, order = c(1, 0, 1)) Coefficients:          ar1      ma1  intercept
2010 Mar 25
1
*** caught segfault *** address 0x18, cause 'memory not mapped'
Hello R Community, I've been run the following codes. However, I've been getting an unusual segfault that I'm unable to trace its origin. Please give me a light to decipher the "caught segfault" Thanks for you attention. Bernardo. > options(STERM='iESS', editor='emacsclient') > rm(list = ls()) > > source("fgenIGLD.R") #RNG
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
2003 Apr 16
0
arima function - estimated coefficients and forecasts
I'm using the arima function to estimate coefficients and also using predict.Arima to forecast. This works nicely and I can see that the results are the same as using SAS's proc arima. I can also take the coefficent estimates for a simple model like ARIMA(2,1,0) and manually compute the forecast. The results agree to 5 or 6 decimal places. I can do this for models with and without
2008 Mar 11
1
messages from mle function
Dears useRs, I am using the mle function but this gives me the follow erros that I don't understand. Perhaps there is someone that can help me. thank you for you atention. Bernardo. > erizo <- read.csv("Datos_Stokes_1.csv", header = TRUE) > head(erizo) EDAD TALLA 1 0 7.7 2 1 14.5 3 1 16.9 4 1 13.2 5 1 24.4 6 1 22.5 > TAN <-
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
2008 Apr 17
1
How to extract vectors from an arima() object and into a data frame?
This should be very easy, but alas, I'm very new to R. My end goal is to calculate p-values from arima(). Let's say I just ran this: > MyModel <- arima(y[1:58], order=c(1,0,0), xreg=MyData[1:58,7:14], > method="ML") > MyModel And I see: arima(x = y[1:58], order = c(1, 0, 0), xreg = MyData[1:58, 7:14], method = "ML") Coefficients: ar1
2013 Jun 07
1
arima time series in R
Hi Could just anyone explain me the coefficients in the output of arima model timeseriesarima <- arima(series, order=c(1,1,2)) > timeseriesarima Series: series ARIMA(1,1,2) Coefficients: ar1 ma1 ma2 0.9744 -1.7695 0.7873 s.e. 0.0310 0.0481 0.0426 sigma^2 estimated as 337.4: log likelihood=-1096.03 AIC=2200.07 AICc=2200.23 BIC=2214.2 ****************
2002 Sep 23
0
arima() in package ts.
I've been trying to get comfy with arima() and associated functions in the ts() package. I'm thinking seriously about using this package, and R generally, in a 4th year intro time series course that I'm teaching this autumn. I have a couple of questions about arima: (1) The help file says that residuals component of the value returned by arima() consists of the
2009 Mar 06
0
modifying a built in function from the stats package (fixing arima) (CONCLUSIONS)
Thanks a lot to everybody that helped me out with this. Conclusions: (1) In order to edit arima in R: >fix(arima) or alternatively: >arima<-edit(arima) (2) This is not contained in the "Introduction to R" manual. (3) A "productive" fix of arima is attached (arma coefficients printed out and error catched so that it doesn't halt parent loops to search for
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 Dec 21
1
matrix to gal object
useR's I need transform the matrix wdat [,1] [,2] [,3] [,4] [,5] [,6] [1,] 0 1 0 1 1 0 [2,] 1 0 0 1 1 0 [3,] 0 0 0 0 1 1 [4,] 1 1 0 0 1 0 [5,] 1 1 1 1 0 0 [6,] 0 0 1 0 0 0 to gal object. How I do with spdep? Thanks in advance for the help. Bernardo. University of Concepci?.
2009 Jun 03
0
Import ARIMA-GARCH coefficients
Hello, I am modelling a Time Serie with ARIMA-GARCH and i have already determined the coefficients ( ARIMA and GARCH) with other software. Now I am trying to do the forecast in R, but i don't know how i can import the coefficients. I will be very pleased if someone help me. Daniel _________________________________________________________________ Mais do que mensagens – conheça
2012 Apr 17
2
Manually reconstructing arima model from coefficients
Colleagues I am a new to R but already love it. I have the following problem: I fitted arima model to my time series like this (please ignore modeling parameters as they are not important now): x = scan("C:/data.txt") x = ts(x, start=1, frequency=1) x.fit<-arima(x, order = c(1,0,0), seasonal = list(order=c(0,0,1))) Now I want to use this model for forecasting and backtesting (!).