ARIMA
Model a series as its own past values plus its own past errors.
ARIMA combines three ideas, one per order. The autoregressive part (p)
makes the forecast a weighted sum of recent values. The differencing part
(d) subtracts consecutive observations until what is left has no trend,
which is what lets the other two parts assume a stable level. The moving
average part (q) lets recent forecast errors feed back in.
It is the standard reference model for a series without a strong seasonal
pattern. For seasonality, prefer :class:ExponentialSmoothing with a
seasonal component, since seasonal ARIMA would need three more orders that
this wrapper does not expose.
The orders are not chosen automatically. d = 1 suits a series that
trends, d = 0 one that hovers around a level, and the DashAI optimizer
can search all three when told to.
References
- [1] https://www.statsmodels.org/stable/generated/statsmodels.tsa.arima.model.ARIMA.html
- [2] https://otexts.com/fpp3/arima.html
Parameters
- p : integer, default=
1 - How many past values the forecast is a weighted sum of, the autoregressive order.
- d : integer, default=
1 - How many times to difference the series before modelling it. 1 removes a straight trend, 0 suits a series that already hovers around a fixed level.
- q : integer, default=
0 - How many past forecast errors feed into the next forecast, the moving average order.
Methods
predict(self, x: 'DashAIDataset') -> 'np.ndarray'
ARIMAForecast forward from the end of the training series.
Parameters
- x : DashAIDataset
- The rows to forecast, whose dates say how far ahead each one is.
Returns
- np.ndarray
- One forecast value per requested row.
train(self, x_train: 'DashAIDataset', y_train: 'DashAIDataset', x_validation: 'DashAIDataset' = None, y_validation: 'DashAIDataset' = None) -> 'ARIMA'
ARIMAFit the ARIMA model to the series.
Parameters
- x_train : DashAIDataset
- The date column. statsmodels is given the values in order and the spacing is assumed regular; the dates are kept so a later partition can be forecast at its own dates.
- y_train : DashAIDataset
- The series to forecast.
- x_validation : DashAIDataset, optional
- Unused.
- y_validation : DashAIDataset, optional
- Unused.
Returns
- ARIMA
- The fitted model.
calculate_metrics(self, split: DashAI.back.core.enums.metrics.SplitEnum = <SplitEnum.VALIDATION: 'validation'>, level: DashAI.back.core.enums.metrics.LevelEnum = <LevelEnum.LAST: 'last'>, log_index: int = None, x_data: 'DashAIDataset' = None, y_data: 'DashAIDataset' = None, fold_index: int = None, inner_fold_index: int = None)
BaseModelCalculate and save metrics for a given data split and level.
Parameters
- split : SplitEnum
- The data split to evaluate (TRAIN, VALIDATION, or TEST). Defaults to SplitEnum.VALIDATION.
- level : LevelEnum
- The metric granularity level (LAST, TRIAL, STEP, or BATCH). Defaults to LevelEnum.LAST.
- log_index : int, optional
- Explicit step index for the metric entry. If None, the next step index is computed automatically. Defaults to None.
- x_data : DashAIDataset, optional
- Input features. If None, the dataset stored in the model for the given split is used. Defaults to None.
- y_data : DashAIDataset, optional
- Target labels. If None, the labels stored in the model for the given split are used. Defaults to None.
compute_metrics(self, split: DashAI.back.core.enums.metrics.SplitEnum = <SplitEnum.TEST: 'test'>, x_data: 'DashAIDataset' = None, y_data: 'DashAIDataset' = None) -> Dict[str, float]
BaseModelCalculate and return metric scores for a given data split.
Parameters
- split : SplitEnum
- The data split to evaluate (TRAIN, VALIDATION, or TEST). Defaults to SplitEnum.VALIDATION.
- x_data : DashAIDataset, optional
- Input features. If None, the dataset stored in the model for the given split is used. Defaults to None.
- y_data : DashAIDataset, optional
- Target labels. If None, the labels stored in the model for the given split are used. Defaults to None.
Returns
- Dict[str, float]
- A dictionary mapping metric names to their computed scores.
get_credential(self, name: str)
ConfigObjectResolve a registered credential component by name.
Parameters
- name : str
- Credential component class name (e.g. "HuggingFaceCredential").
Returns
- BaseCredential
- An instance of the requested credential component.
get_metadata(cls) -> Dict[str, Any]
BaseModelGet metadata values for the current model.
Returns
- Dict[str, Any]
- Dictionary containing UI metadata such as the model icon used in the DashAI frontend.
get_schema(cls) -> dict
ConfigObjectGenerates the component related Json Schema.
Returns
- dict
- Dictionary representing the Json Schema of the component.
load(filename: str) -> Any
ForecastingModelDeserialise a model from disk using joblib.
Parameters
- filename : str
- Path to the file previously written by :meth:
save.
Returns
- ForecastingModel
- The loaded model instance.
predict_prepared(self, features: Any) -> Any
BaseModelPredict from data that is already in this model's feature space.
Parameters
- features : pandas.DataFrame or numpy.ndarray
- Feature matrix as returned by
prepare_dataset(..., is_fit=False). No further preparation is applied to it.
Returns
- Any
- The same kind of output as
predict: predicted values for regressors, class probabilities for DashAI classifiers.
predict_proba_prepared(self, features: Any) -> Any
BaseModelReturn class probabilities for data already in the feature space.
Parameters
- features : pandas.DataFrame or numpy.ndarray
- Feature matrix as returned by
prepare_dataset(..., is_fit=False).
Returns
- numpy.ndarray
- Array of shape
(n_samples, n_classes)with class probabilities.
prepare_dataset(self, dataset: 'DashAIDataset', is_fit: bool = False) -> 'DashAIDataset'
BaseModelHook for model specific preprocessing of input features.
Parameters
- dataset : DashAIDataset
- The input dataset to preprocess.
- is_fit : bool
- Whether the call is part of a fitting phase. Defaults to False.
Returns
- DashAIDataset
- The preprocessed dataset ready to be fed into the model.
prepare_output(self, dataset: 'DashAIDataset', is_fit: bool = False) -> 'DashAIDataset'
BaseModelHook for model-specific preprocessing of output targets.
Parameters
- dataset : DashAIDataset
- The output dataset (target labels) to preprocess.
- is_fit : bool
- Whether the call is part of a fitting phase. Defaults to False.
Returns
- DashAIDataset
- The preprocessed output dataset.
save(self, filename: str) -> None
ForecastingModelSerialise the model to disk using joblib.
Parameters
- filename : str
- Destination file path where the model will be written.
validate_and_transform(self, raw_data: dict) -> dict
ConfigObjectIt takes the data given by the user to initialize the model and returns it with all the objects that the model needs to work.
Parameters
- raw_data : dict
- A dictionary with the data provided by the user to initialize the model.
Returns
- dict
- A validated dictionary with the necessary objects.