SECAI Core · phase 15 of 15 · noun

Model drift

A phenomenon wherein the statistical properties of the target variable or features of a machine learning model change over time, leading to a reduction in model performance.

The Explain card

Plain English
Model drift is the decline in a model's performance over time because the statistical relationships it learned, between its features and its target, no longer hold in the real world.
Example
A fraud model learned that late-night foreign transactions signal fraud. After the business expands internationally, that pattern becomes normal behavior, and the model starts flagging legitimate customers while missing newer fraud types.
Why it matters
A drifting model gives false confidence. Defenders need scheduled performance checks and retraining triggers, because a model that was accurate at launch can become a liability.
Hook
The model did not change, the world did.

Word knowledge

How the word is built, where it came from, and what it sits beside in memory.

In a sentence

Security engineers monitor authentication scores for model drift when new attack patterns alter a deployed fraud detector's alert distribution.

Why these words
  • model Latin modulus, small measure, through Italian modello and French modèle identifies the trained computational system being monitored
  • drift Old English drīfan, to drive or move suggests gradual movement away from an earlier state
Where it came from
Origin
an English technical compound combining model with the figurative sense of drift
Entered the language
2000s
What changed
Drift developed from physical movement into a term for gradual, often unintended change, then joined model in machine learning usage.
How it is spelled
Pattern
It is an open compound written as two separate lowercase words.
Pattern
Drift retains the final consonant cluster -ft.

Spelled like

  • data drift
  • concept drift
  • feature drift
Broken into chunks
  • model
    • model monitoring
    • model evaluation
  • drift
    • data drift
    • concept drift
What it sits beside

Same subject

Same shape

machine learning drift terms

Where it sits in the deck

Phase 15: MLOps, Continuous Delivery, and Operational Resilience

Close the loop — operational practices, drift management, and delivery discipline that keep deployed AI systems healthy, current, and continuously improving.