arima
班级:regARIMA
Convert regression model with ARIMA errors to ARIMAX model
Syntax
Arimax = Arima(MDL)
[Arimax,Xnew] = Arima(MDL,名称,值)
描述
Thearima
对象函数将带有Arima错误的指定回归模型转换(regARIMA
model object) to the equivalent ARIMAX model (arima
model object). To create an ARIMAX model directly, seearima
。
使用ARIMA时间序列错误转换单变量回归模型Arimax
= arima(MDL
)MDL
to a model of typearima
包括回归分量(ARIMAX)。
[
returns an updated regression matrix of predictor data using additional options specified by one or moreArimax
,XNew
] = Arima(Arima(MDL
,Name,Value
)Name,Value
配对参数。
Input Arguments
|
Regression model with ARIMA time series errors, as created by |
Name-Value Arguments
将可选的参数对Name1=Value1,...,NameN=ValueN
, whereName
是个argument name and价值
是相应的值。名称值参数必须在其他参数之后出现,但是对的顺序并不重要。
Before R2021a, use commas to separate each name and value, and encloseName
in quotes.
|
预测数据的回归组件 最后一行 每一列 |
Output Arguments
|
Arimax模型等于具有Arima错误的回归模型 |
|
Updated predictor data matrix for the regression component of
每一列 |
例子
算法
让X表示串联预测数据矢量(或设计矩阵)的矩阵和βdenote the regression component for the regression model with ARIMA errors,MDL
。
如果指定
X
, thenarima
returnsXNew
in a certain format. Suppose that the nonzero autoregressive lag term degrees ofMDL
是0 <a1<a2< ...<P, which is the largest lag term degree. The software obtains these lag term degrees by expanding and reducing the product of the seasonal and nonseasonal autoregressive lag polynomials, and the seasonal and nonseasonal integration lag polynomialsThe first column of
XNew
isXβ。第二列
XNew
is a sequence ofa1NaN
s, and then the product whereThejth column of
XNew
is a sequence ofajNaN
s, and then the product whereThe last column of
XNew
is a sequence ofapNaN
s, and then the product where
Suppose that
MDL
是Arima(3,1,0)错误的回归模型,并且ϕ1= 0.2 andϕ3= 0.05. Then the product of the autoregressive and integration lag polynomials isThis implies that
arimax.beta
is[1 -1.2 0.02 -0.05 0.05]
和XNew
iswherexj是个jth row ofX。
If you do not specify
X
, thenarima
returnsXNew
作为无行的空矩阵,一加上一个非零自动回归系数的数量MDL
columns.