Machine Learning System Design Interview, issue 16, Dec 2, 2025
The P-Value Mirage
Machine Learning Research Engineer interview at Google DeepMind, and the interviewer asks:
“We need an automated trigger for model retraining based on feature drift. How do you implement it?”
Why KS tests fail at scale and how magnitude-based drift metrics save your retraining pipeline.
The full answer, with the mechanism and the arithmetic, is for paid subscribers on Substack.