climpred.metrics._mse

climpred.metrics._mse(forecast, verif, dim=None, **metric_kwargs)[source]

Mean Sqaure Error (MSE).

MSE = \overline{(f - o)^{2}}

The average of the squared difference between forecasts and verification data. This incorporates both the variance and bias of the estimator. Because the error is squared, it is more sensitive to large forecast errors than mae, and thus a more conservative metric. For example, a single error of 2°C counts the same as two 1°C errors when using mae. On the other hand, the 2°C error counts double for mse. See Jolliffe and Stephenson, 2011.

Parameters
  • forecast (xarray object) – Forecast.

  • verif (xarray object) – Verification data.

  • dim (str) – Dimension(s) to perform metric over.

  • metric_kwargs (dict) – see mse()

Details:

minimum

0.0

maximum

perfect

0.0

orientation

negative

See also

Reference:
  • Ian T. Jolliffe and David B. Stephenson. Forecast Verification: A Practitioner’s Guide in Atmospheric Science. John Wiley & Sons, Ltd, Chichester, UK, December 2011. ISBN 978-1-119-96000-3 978-0-470-66071-3. URL: http://doi.wiley.com/10.1002/9781119960003.

Example

>>> HindcastEnsemble.verify(metric='mse', comparison='e2o', alignment='same_verifs',
...     dim='init')
<xarray.Dataset>
Dimensions:  (lead: 10)
Coordinates:
  * lead     (lead) int32 1 2 3 4 5 6 7 8 9 10
    skill    <U11 'initialized'
Data variables:
    SST      (lead) float64 0.006202 0.006536 0.007771 ... 0.02417 0.02769