ARIMAProcess
ARIMAProcess[{a1,…,ap},d,{b1,…,bq},v]
represents an autoregressive integrated moving-average process such that its difference is a weakly stationary ARMAProcess[{a1,…,ap},{b1,…,bq},v].
ARIMAProcess[{a1,…,ap},d,{b1,…,bq},Σ]
represents a vector ARIMA process (y1(t),… ,yn(t)) such that its (d,…,d) difference is a vector weakly stationary ARMAProcess.
ARIMAProcess[{a1,…,ap},{d1,…,dn},{b1,…,bq},Σ]
represents a vector ARIMA process (y1(t),… ,yn(t)) such that its (d1,…,dn) difference is a vector weakly stationary ARMAProcess.
ARIMAProcess[{a1,…,ap},d,{b1,…,bq},v,init]
represents an ARIMA process with initial data init.
ARIMAProcess[c,…]
represents an ARIMA process with a constant c.
Details
- ARIMAProcess is a discrete-time and continuous-state random process.
- An ARIMAProcess[…,d,…,v] has a polynomial trend of degree d for d≥1.
- The ARIMA process is described by the difference equation , where is the state output, is the white noise input, is the shift operator and the constant c is taken to be zero if not specified.
- The initial data init can be given as a list {…,y[-2],y[-1]} or a single-path TemporalData object with time stamps understood as {…,-2,-1}.
- A scalar ARIMA process should have real coefficients ai, bj, and c, non-negative integer integration order d, and a positive variance v.
- An -dimensional vector ARIMA process should have real coefficient matrices ai and bj of dimensions ×, real vector c of length , integer non-negative integrating orders di or integer non-negative integrating order d, and the covariance matrix Σ should be symmetric positive definite of dimensions ×.
- The ARIMA process with zero constant has transfer function , where , , and where is an -dimensional unit.
- ARIMAProcess[p,d,q] represents an ARIMA process with autoregressive and moving average orders p and q and integration order d for use in EstimatedProcess and related functions.
- ARIMAProcess can be used with such functions as CovarianceFunction, RandomFunction, and TimeSeriesForecast.
Examples
open allclose allBasic Examples (2)
Scope (25)
Basic Uses (9)
Simulate an ensemble of paths:
Simulate with given precision:
Simulate a process with given initial values:
In the presence of a nonzero constant:
Simulate a two-dimensional process:
Create a 2D sample path function from the data:
The color of the path is the function of time:
Create a 3D sample path function with time:
Color of the path is the function of time:
Simulate a three-dimensional process:
Create a sample path function from the data:
The color of the path is the function of time:
Use TimeSeriesModel to automatically find orders:
Plot the data and the forecasted values:
Find a forecast for a vector-valued time series process:
Stationarity and Invertibility (2)
Estimation Methods (5)
The available methods for estimating an ARIMAProcess:
Method of moments admits the following solvers:
This method allows for fixed parameters:
Some relations between parameters are also permitted:
Maximum conditional likelihood method allows the following solvers:
This method allows for fixed parameters:
Some relations between parameters are also permitted:
Maximum likelihood method allows the following solvers:
This method allows for fixed parameters:
Some relations between parameters are also permitted:
Spectral estimator allows to specify windows used for PowerSpectralDensity calculation:
Spectral estimator allows following solvers:
Process Slice Properties (5)
Single time SliceDistribution:
Multiple time slice distributions:
Slice distribution of a vector-valued time series:
First-order probability density function:
Compute the expectation of an expression:
Calculate the probability of an expression:
Skewness and kurtosis are constant:
CentralMoment and its generating function:
FactorialMoment has no closed form for symbolic order:
Cumulant and its generating function:
Representations (4)
Approximate with an MA process:
Approximate with an AR process:
Represent as the equivalent ARMA process:
It is usually not weakly stationary:
TransferFunctionModel representation:
StateSpaceModel representation:
Applications (3)
Forecast annual revenue of commercial airlines:
Data has a linear trend that can be confirmed using UnitRootTest:
Fit an ARIMA model to the time series:
Find the forecast for 10 years ahead:
Global yearly mean temperature compared to 1951–1980 baseline:
Find order of integration with UnitRootTest:
Estimate an ARIMA with integration order equal to 1:
Find the forecast for the next 20 years:
Properties & Relations (4)
ARIMAProcess is a generalization of an ARMAProcess:
ARIMAProcess is a generalization of an ARProcess:
ARIMAProcess is a generalization of an MAProcess:
ARIMA process follows WienerProcess in discrete steps:
Possible Issues (5)
Multi-time-slice properties may not evaluate for symbolic time stamps:
Some properties are defined only for weakly stationary processes:
Use FindInstance to find a weakly stationary process:
Slice distribution properties with inexact parameters may be ill-conditioned for symbolic times:
The negative result is incorrect:
Or use exact values of parameters:
ToInvertibleTimeSeries does not always exist:
There are zeros of the TransferFunctionModel on the unit circle:
The method of moments may not find a solution in estimation:
Neat Examples (2)
Simulate a three-dimensional ARIMAProcess:
Simulate paths from an ARIMA process:
Take a slice at 50 and visualize its distribution:
Plot paths and histogram distribution of the slice distribution at 50:
Text
Wolfram Research (2012), ARIMAProcess, Wolfram Language function, https://reference.wolfram.com/language/ref/ARIMAProcess.html (updated 2014).
CMS
Wolfram Language. 2012. "ARIMAProcess." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2014. https://reference.wolfram.com/language/ref/ARIMAProcess.html.
APA
Wolfram Language. (2012). ARIMAProcess. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ARIMAProcess.html