def __init__(
        self,
        alias: str = "RWD",
        prediction_intervals: Optional[ConformalIntervals] = None,
    ):
        r"""RandomWalkWithDrift model.

        A variation of the naive method allows the forecasts to change over time.
        The amout of change, called drift, is the average change seen in the historical data.

        $$\hat{y}_{t+1} = y_t+\frac{1}{t-1}\sum_{j=1}^t (y_j-y_{j-1}) = y_t+ \frac{y_t-y_1}{t-1}$$

        From the previous equation, we can see that this is equivalent to extrapolating a line between
        the first and the last observation.

        References
        ----------
        [Rob J. Hyndman and George Athanasopoulos (2018). "forecasting principles and practice, Simple Methods"](https://otexts.com/fpp3/simple-methods.html).

        Parameters
        ----------
        alias : str
            Custom name of the model.
        prediction_intervals : Optional[ConformalIntervals]
            Information to compute conformal prediction intervals.
            By default, the model will compute the native prediction
            intervals.
        """
        self.alias = alias
        self.prediction_intervals = prediction_intervals
RandomWalkWithDrift model.

        A variation of the naive method allows the forecasts to change over time.
        The amout of change, called drift, is the average change seen in the historical data.

        $$\hat{y}_{t+1} = y_t+\frac{1}{t-1}\sum_{j=1}^t (y_j-y_{j-1}) = y_t+ \frac{y_t-y_1}{t-1}$$

        From the previous equation, we can see that this is equivalent to extrapolating a line between
        the first and the last observation.

        References
        ----------
        [Rob J. Hyndman and George Athanasopoulos (2018). "forecasting principles and practice, Simple Methods"](https://otexts.com/fpp3/simple-methods.html).

        Parameters
        ----------
        alias : str
            Custom name of the model.
        prediction_intervals : Optional[ConformalIntervals]
            Information to compute conformal prediction intervals.
            By default, the model will compute the native prediction
            intervals.
        
python/statsforecast/models.py