A team deploys a model using Vertex AI and wants to monitor for concept drift. What should they track?
Concept drift is a change in the underlying function mapping inputs to outputs.
Why this answer
Concept drift refers to a change in the underlying relationship between the input features and the target variable over time, which degrades model performance. In Vertex AI, monitoring this requires tracking the statistical relationship between inputs and outputs (e.g., via prediction residuals or model performance metrics), not just the input distribution alone. Option D correctly identifies this need, as concept drift is fundamentally about the input-output mapping shifting, even if the input distribution remains stable.
Exam trap
Google Cloud often tests the distinction between data drift (input distribution changes) and concept drift (input-output relationship changes), and the trap here is that candidates confuse the two, picking Option C because they think monitoring input data is sufficient for detecting all model degradation.
How to eliminate wrong answers
Option A is wrong because the number of prediction requests measures traffic volume, not data or concept drift; it is a scaling or operational metric, not a model quality metric. Option B is wrong because prediction latency measures inference speed, which is a performance indicator unrelated to the statistical properties of data or model relationships. Option C is wrong because changes in input data distribution represent data drift (covariate shift), not concept drift; while data drift can cause concept drift, monitoring only input distribution misses shifts in the input-output relationship that occur without distributional changes.