similar to: [R} seasonal differencing

Displaying 20 results from an estimated 7000 matches similar to: "[R} seasonal differencing"

2015 May 21
3
Fix for bug in arima function
On 21 May 2015, at 12:49 , Martin Maechler <maechler at lynne.stat.math.ethz.ch> wrote: >>>>>> peter dalgaard <pdalgd at gmail.com> >>>>>> on Thu, 21 May 2015 11:03:05 +0200 writes: > >> On 21 May 2015, at 10:35 , Martin Maechler <maechler at lynne.stat.math.ethz.ch> wrote: > >>>> >>>> I noticed that
2007 Oct 12
1
Differencing data by groups
Colleagues, I am analyzing data collected during oceanographic cruises. We have conducted many cruises over the last decade. On each cruise we visit ~50 stations. At each station (termed EventNum)we lower an instrument that measures depth, temperature, salinity and oxygen every few seconds as it is lowered through the water. Data from all EventNums on all cruises are stacked, generating a data
2015 May 21
2
Fix for bug in arima function
On 21 May 2015, at 10:35 , Martin Maechler <maechler at lynne.stat.math.ethz.ch> wrote: >> >> I noticed that the 3.2.1 release cycle is about to start. Is there any >> chance that this fix will make it into the next version of R? >> >> This bug is fairly serious: getting the wrong variance estimate leads to >> the wrong log-likelihood and the wrong
2011 Jul 07
1
Discussion on time series analysis and the use and misuse of Differencing
How does the R module ARIMA account for unspecified deterministic structure such as seasonal pulses, level shifts, local time trends and regular pulses without needing to ask the user to intervene to specify this? I have attached a Makradakis paper which hammers Box-Jenkins approach to this problem of nonstationarity. I have also included a recent discussion from stackexchange which you might
2013 Sep 09
1
Fitting Arima Models and Forecasting Using Daily Historical Data
Hello everyone, I was trying to fit an arima model to a daily historical data, but, for some reason, havent been able to. I basically have 212 observations (from 12/1/2012 to 06/30/2013) containing the number of transits for a particular vessel. The following messages are produced by R: dailytrans.fit<-arima(dailytrans$transits, order=c(0,1,2), seasonal=list(order=c(0,1,2), period=365),
2015 Apr 20
2
Fix for bug in arima function
There is currently a bug in the arima function. Namely, for arima models with differencing or seasonal differencing, the innovation variance estimator uses the wrong denominator whenever xreg is non-null. This is the case, for example, when fitting an ARIMA(p,1,q) model with a drift term (common in financial applications). I reported the bug (and a fix) at
2010 Aug 30
1
How to Remove Autocorrelation from Simple Moving Average time series
Hi R experts, I am trying to remove autocorrelation from Simple Moving Average time series. I know that this can be done by using seasonal ARIMA like, library(TTR) data <- rnorm(252) n=21 sma_data=SMA(data,n) sma_data=sma_data[-1:-n] acf(sma_data,length(sma_data))
2005 Oct 31
1
how to optimise cross-correlation plot to study time lag between time-series?
Dear R-help, How could a cross-correlation plot be optimized such that the relationship between seasonal time-series can be studied? We are working with strong seasonal time-series and derived a cross-correlation plot to study the relationship between time-series. The seasonal variation however strongly influences the cross-correlation plot and the plot seems to be ?rather? symmetrical (max
2004 Sep 27
1
optim error in arima
Hello, I'm fitting a series of ARIMA models to a data set to compare fits. After taking the logs of the data and then differencing them to induce stationarity, I execute arima( y, order=c( p, 0, q ), seasonal=list( order=c( P, 0, Q ), period=7 ) ) for various values of p, q, P and Q. For one set of these values, I get Error in optim(init[mask], armafn, method = "BFGS", hessian
2008 May 15
1
plotting predictions
I have the following model: m1.dis=arima(diff(diff(log(ts1),lag=12)),order=c(0,1,1),seasonal=list(order=c(0,1,1),period=12)) I would like to know how to plot the correct predictions in the original units because I am trying the following code but it is not working. I believe that there must be something to account for the differencing.
2000 Nov 30
1
means in arima0 (PR#754)
Full_Name: Arto Luoma Version: 1.1.0 OS: Windows 98 Submission from: (NULL) (153.1.53.119) In arima0 it is possible to specify whether the mean of the original series is included in the model or not. However, it is not possible to specify whether the mean of the differenced series is included. It seems that it is not included. However, if differencing is used to eliminate trend, the mean of the
2012 Aug 09
4
R Commander - Time Series
Hello all, I'm just starting to learn R and I heard a good way of doing that was R Commander. For my work I use a lot of time series, so I installed (and loaded) R Commander with epack. When I go to Ts-Models, after loading my data, I click on ARIMA Models tab. I load my variable D1 Ln Demand (1st differenced ln demand). I set my regular and seasonal p d q settings hit run and I get: [1]
2006 Nov 30
1
bug in arima? (PR#9404)
I don't think arima works exactly the way one would expect when there is differencing. What I think should happen is that by default the mean of the differenced series is estimated and if include.mean=F, then it is not. This is not what happens. Instead when there is differencing the include.mean argument is ignored. Now I guess, someone could argue that the mean of the original series
2004 Jul 04
1
Re: Seasonal ARMA model
> It might clarify your thinking to note that a seasonal ARIMA model > is just an ``ordinary'' ARIMA model with some coefficients > constrained to be 0 in an efficient way. E.g. a seasonal AR(1) s = > 4 model is the same as an ordinary (nonseasonal) AR(4) model with > coefficients theta_1, theta_2, and theta_3 constrained to be 0. You > can get the same answer as from
2010 Oct 29
3
Dickey Fuller Test
Dear Users, please help with the following DF test: ===== library(tseries) library(timeSeries) Y=c(3519,3803,4332,4251,4661,4811,4448,4451,4343,4067,4001,3934,3652,3768 ,4082,4101,4628,4898,4476,4728,4458,4004,4095,4056,3641,3966,4417,4367 ,4821,5190,4638,4904,4528,4383,4339,4327,3856,4072,4563,4561,4984,5316 ,4843,5383,4889,4681,4466,4463,4217,4322,4779,4988,5383,5591,5322,5404
2002 Nov 18
1
Prediction from arima() object (library ts) (PR#2305)
Full_Name: Allan McRae Version: 1.6.0 OS: Win 2000 P Submission from: (NULL) (129.215.190.229) When using predict.Arima in library ts(), it appears differencing is only accounted for in the first step of prediction and so any trend is not apparent in the predictions. The example shows the difference between the predictions of an arima(1,1,1) model and the backtransformed predictions of an
2004 Jul 01
2
[gently off topic] arima seasonal question
Hello R People: When using the arima function with the seasonal option, are the seasonal options only good for monthly and quarterly data, please? Also, I believe that weekly and daily data are not appropriate for seasonal parm estimation via arima. Is that correct, please? Thanks, Sincerely, Laura Holt mailto: lauraholt_983 at hotmail.com download!
2004 Jan 14
1
seasonal fractional ARIMA models
Hello, does anyone know about: a) simulating seasonal ARIMA models? arima out of package ts can fit it, but it does not look like it can simulates data from seasonal models b) fitting and simulating fractional seasonal ARIMA models? Hints will be appreciated, Henning -- Henning Rust Potsdam Institute for Climate Impact Research Dept. Integrated Systems Analysis Tel.: #49/331/288-2596
2012 Aug 01
4
how to calculate seasonal mean for temperatures
Hello everybody, I need to calculate seasonal means with temperature data for my work. I have 70 files coming from weather stations, which looks like this for example: startdate <- as.POSIXct("01/01/2006", format = "%d/%m/%Y") enddate <- as.POSIXct("05/01/2006", format = "%d/%m/%Y") date <- seq(from = startdate, to = enddate, by =
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