Evaluation

Model drift

Model drift is a change over time that degrades or alters model behavior.

months in productionaccuracyaccuracyworld changed
Model drift is a change over time that degrades or alters model behavior. Values shown in the worked visual are illustrative unless the labels state otherwise.

How it works

Input distributions, target relationships, or user behavior can shift after deployment. Detection requires reference windows and actionable thresholds.

A concrete example

Illustrative: positive-class prevalence rises from 8% in training to 15% this month.

Do not confuse it with Data drift

data drift is input change; model drift is the broader observed behavior change and may have several causes.

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