Explain key ML theory and techniques
Company: Amazon
Role: Machine Learning Engineer
Category: Machine Learning
Difficulty: hard
Interview Round: Onsite
Quick Answer: This question evaluates a candidate's understanding of core machine learning theory and practical modeling techniques, including parallelism in gradient-boosted trees (XGBoost), layer normalization in Transformer layers, multimodal neural network design and fusion strategies, collaborative filtering approaches, multi-armed bandit problem formulation and algorithms, and the probabilistic derivation and interpretation of logistic regression. It is commonly asked in technical interviews to assess breadth and depth across scalability, neural architecture and normalization choices, recommendation and online decision-making methods, and statistical modeling and regularization, and it falls within the Machine Learning domain testing both conceptual understanding and practical application.