VAR
VAR model from statsmodels.
Direct interface to statsmodels.tsa.vector_ar.
A VAR model is a generalisation of the univariate autoregressive model to multivariate time series, see [1]_.
Quickstart
from sktime.forecasting.var import VAR
estimator = VAR(maxlags=None, method='ols', verbose=False, trend='c', missing='none', dates=None, freq=None, ic=None, random_state=None)Parameters(9)
- maxlags: int or None (default=None)
- Maximum number of lags to check for order selection, defaults to 12 * (nobs/100.)**(1./4)
- methodstr {“ols”} (default=”ols”)
Estimation method to use.
"ols"is the only estimation method offered bystatsmodels.- verbosebool (default=False)
- Print order selection output to the screen
- trendstr {“c”, “ct”, “ctt”, “n”} (default=”c”)
“c” - add constant
“ct” - constant and trend
“ctt” - constant, linear and quadratic trend
“n” - co constant, no trend
Note that these are prepended to the columns of the dataset.
- missingstr {“none”, “drop”, “raise”} (default=”none”)
A string specifying how missing values are handled.
"none"- no nan checking is done"drop"- any observations with nans are dropped"raise"- an error is raised if nans are present
- freqstr, tuple, datetime.timedelta, DateOffset or None, optional (default=None)
A frequency specification for either
datesor the row labels from the endog / exog data. A pandas offset, or one of the strings"B"- business day"D"- calendar day"W"- weekly"M"- monthly"A"- annual"Q"- quarterly
This is optional if
datesare provided.- datesarray_like of datetime, optional (default=None)
An array like object containing
datetimeobjects, which must match the number of rows of the endogenous data. If a pandas object with aDatetimeIndexis passed as data, that index is used, and this argument can be left asNone.- ic: One of {‘aic’, ‘fpe’, ‘hqic’, ‘bic’, None} (default=None)
Information criterion to use for VAR order selection.
“aic”: Akaike
“fpe”: Final prediction error
“hqic”: Hannan-Quinn
“bic”: Bayesian a.k.a. Schwarz
- random_stateint, RandomState instance or None, optional,
- default=None - If int, random_state is the seed used by the random number generator; If RandomState instance, random_state is the random number generator; If None, the random number generator is the RandomState instance used by np.random.
Examples
>>> from sktime.forecasting.var import VAR
>>> from sktime.datasets import load_longley
>>> _, y = load_longley ()
>>> forecaster = VAR ()
>>> forecaster. fit (y) VAR(
... )
>>> y_pred = forecaster. predict (fh = [1, 2, 3 ])References
- [1] Athanasopoulos, G., Poskitt, D. S., & Vahid, F. (2012). Two canonical VARMA forms: Scalar component models vis-à-vis the echelon form. Econometric Reviews, 31(1), 60-83, 2012.