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Concept drift

By Updated

A change in the relationship between a system's inputs and the correct output, so the same input should now get a different answer 1. Unlike data drift, it shows only in outcomes: in production it appears in performance on fresh labels and in change-point tests on the error rate.

Developed in
ch. 11, Contrast pairs
ch. 15, Drift: what moves and how to see it
Chapters
ch. 11, AI Defined · ch. 15, Deployment
Contrast with
Data drift
Source
1 numbered reference, listed below

Commonly confused

  • Data drift versus Concept drift

    Data drift
    A change in the distribution of the inputs a system sees in production relative to the data it was validated on, such as a new customer segment or a changed upstream form.
    Concept drift
    A change in the relationship between a system's inputs and the correct output, so the same input should now get a different answer.

    The differenceThe inputs change, against the relationship between inputs and the right answer changing.

    Why it mattersThe first shows in input monitors before labels arrive; the second only in outcomes on fresh labels.

Where it is used

3 chapters of the Body of Knowledge use the term. Each link opens the first section that does.

Patterns that use this term

One pattern page uses the term.

  • Drift

    The gradual divergence of a model's inputs, outputs or performance from its validated baseline over time; a runtime signal that a control or eval must catch.

  • Explainability

    In NIST's framing, a representation of the mechanisms behind a system's operation: how a decision was made.

  • Opacity

    The inability of a person to follow how a system reached an output.

  • Transparency

    In NIST's framing, how far information about an AI system and its outputs reaches the people who interact with it: what happened.

Sources

  1. [1] "Learning under Concept Drift: A Review" (IEEE TKDE 31(12); detection, understanding and adaptation; arXiv 2004.05785). Lu et al.. 2018. https://arxiv.org/abs/2004.05785 (verified: primary)

Definitions of legal terms paraphrase the cited text, which governs. Dated statements are as of .

Cite this term

García Aibar, J. (2026). Concept drift. In AI Governance Engineering: The Thesis & Body of Knowledge (v0.5.0), Glossary. https://doi.org/10.5281/zenodo.22956197. https://aigovernanceengineer.com/glossary/concept-drift. CC BY 4.0

BibTeX

@misc{aige2026conceptdrift,
  author  = {Jorge García Aibar},
  title   = {{Concept drift}},
  note    = {Glossary, AI Governance Engineering: The Thesis \& Body of Knowledge, version 0.5.0},
  year    = {2026},
  doi     = {10.5281/zenodo.22956197},
  url     = {https://aigovernanceengineer.com/glossary/concept-drift}
}