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Brier Score

scoringrules.brier_score

brier_score(
    observations: ArrayLike,
    forecasts: ArrayLike,
    /,
    *,
    backend: Backend = None,
) -> Array

Compute the Brier Score (BS).

The BS is formulated as

\[ BS(f, y) = (f - y)^2, \]

where \(f \in [0, 1]\) is the predicted probability of an event and \(y \in \{0, 1\}\) the actual outcome.

Parameters:

Name Type Description Default
observations ArrayLike

Observed outcome, either 0 or 1.

required
forecasts NDArray

Forecasted probabilities between 0 and 1.

required
backend Backend

The name of the backend used for computations. Defaults to 'numpy'.

None

Returns:

Name Type Description
brier_score NDArray

The computed Brier Score.