Evaluation, Testing & Optimization·Task 4.4·Bloom: evaluate·Difficulty 4/5·9 min read·Updated 2026-07-14

Change Attribution: Model Drift vs Data Drift vs Model Update

Diagnose system issues (prompt failure, hallucinations, model mismatch)

SUBy Solomon UdohReviewed by Solomon UdohAI-assisted · human-reviewed
In short
Change attribution distinguishes the three distinct causes a monitored metric can move for. Model drift is a gradual change in the model behaviour on stable inputs over time. Data drift is a change in the distribution of inputs the system receives, with the model itself unchanged. Model update effects occur when the model version changed and the new version behaves differently on existing inputs. These three require different mitigations, so mixing them up when a metric moves produces the wrong fix.

Full concept guide coming soon

We are building the in-depth, exam-aligned guide for this knowledge point. In the meantime, explore the prerequisites and related concepts below, watch the official Anthropic Academy lessons, and start an adaptive study session to master it with Archie.

Watch and learn

Official Anthropic Academy lessons first, then hand-picked walkthroughs. Videos load only when you press play.

No videos curated for this concept yet

We are still curating the best official and community videos for this topic.

References & primary sources

Adaptive study

Master this concept with Archie

Practice it inside an adaptive study session. Archie, your Socratic AI tutor, tracks your mastery with Bayesian Knowledge Tracing and schedules the perfect next review.

Start studying