A company deploys a model with SageMaker and wants to monitor for concept drift. They have noticed that the relationship between input features and the target variable has changed, causing model accuracy to degrade. However, the input data distribution remains stable. Which type of drift is this, and what is the most appropriate response strategy?
Concept drift is a change in P(y|x). Retraining with recent labeled data adjusts the model to the new relationship.
Why this answer
This is concept drift because the relationship between input features and the target variable has changed while the input data distribution remains stable. The most appropriate response is to retrain the model with newly collected labeled data that reflects the current relationship, as concept drift requires updating the model's learned mapping from features to labels.
Exam trap
The trap here is that candidates confuse concept drift with data drift, assuming any drift requires updating baseline statistics, when in fact concept drift demands retraining with fresh labeled data to realign the model with the new feature-target relationship.
How to eliminate wrong answers
Option A is wrong because ignoring concept drift will cause continued model accuracy degradation, even if the input distribution is stable; concept drift directly impacts predictive performance. Option B is wrong because this is not data drift (input distribution is stable), and updating baseline statistics would not address the changed feature-target relationship. Option D is wrong because data drift refers to changes in input data distribution, not the feature-target relationship, so retraining with the latest training data under the assumption of data drift is a misdiagnosis.