sklearn.metrics
.mean_tweedie_deviance¶
-
sklearn.metrics.
mean_tweedie_deviance
(y_true, y_pred, *, sample_weight=None, power=0)[source]¶ Mean Tweedie deviance regression loss.
Read more in the User Guide.
- Parameters
- y_truearray-like of shape (n_samples,)
Ground truth (correct) target values.
- y_predarray-like of shape (n_samples,)
Estimated target values.
- sample_weightarray-like of shape (n_samples,), default=None
Sample weights.
- powerfloat, default=0
Tweedie power parameter. Either power <= 0 or power >= 1.
The higher
p
the less weight is given to extreme deviations between true and predicted targets.power < 0: Extreme stable distribution. Requires: y_pred > 0.
power = 0 : Normal distribution, output corresponds to mean_squared_error. y_true and y_pred can be any real numbers.
power = 1 : Poisson distribution. Requires: y_true >= 0 and y_pred > 0.
1 < p < 2 : Compound Poisson distribution. Requires: y_true >= 0 and y_pred > 0.
power = 2 : Gamma distribution. Requires: y_true > 0 and y_pred > 0.
power = 3 : Inverse Gaussian distribution. Requires: y_true > 0 and y_pred > 0.
otherwise : Positive stable distribution. Requires: y_true > 0 and y_pred > 0.
- Returns
- lossfloat
A non-negative floating point value (the best value is 0.0).
Examples
>>> from sklearn.metrics import mean_tweedie_deviance >>> y_true = [2, 0, 1, 4] >>> y_pred = [0.5, 0.5, 2., 2.] >>> mean_tweedie_deviance(y_true, y_pred, power=1) 1.4260...