Surapprentissage

Résumé

vignette|300x300px|La ligne verte représente un modèle surappris et la ligne noire représente un modèle régulier. La ligne verte classifie trop parfaitement les données d'entrainement, elle généralise mal et donnera de mauvaises prévisions futures avec de nouvelles données. Le modèle vert est donc finalement moins bon que le noir. En statistique, le surapprentissage, ou sur-ajustement, ou encore surinterprétation (en anglais « overfitting »), est une analyse statistique qui correspond trop précisément à une collection particulière d'un ensemble de données. Ainsi, cette analyse peut ne pas correspondre à des données supplémentaires ou ne pas prévoir de manière fiable les observations futures. Un modèle surajusté est un modèle statistique qui contient plus de paramètres que ne peuvent le justifier les données. Apprentissage automatique Le problème existe aussi en apprentissage automatique . Il est en général provoqué par un mauvais dimensionnement de la structure utilisée po

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