Principal ML Scientist

Expedia is looking for a Principal Machine Learning Scientist to lead the technical strategy and execution for LLM-powered AI agent servicing. You will define and drive the transformation to scalable voice and chat self-service experiences while improving customer and operational outcomes.

• Define and lead the ML strategy for personalization/search/recommendations/pricing/fraud/risk or GenAI experiences
• Formulate business needs into well-posed ML problems with success metrics
• Design and implement state-of-the-art ML models and own them through production
• Partner with engineering to productionize models and improve data/feature pipelines
• Lead experiment design and evaluation including A/B tests and offline eval

The role focuses on designing and owning state-of-the-art ML models (deep learning, representation learning, causal inference, bandits, and LLM/GenAI where appropriate) and productionizing them through robust data and feature pipelines. You will lead experiment design and evaluation, including A/B tests and offline evaluation, and partner with engineering to meet reliability, latency, and scalability requirements.

The ideal candidate is a senior-to-principal ML scientist who has led ML strategy and shipped production-grade models, with strong experience in personalization and modern GenAI/LLM-based agent systems. They can design rigorous experiments (A/B tests and offline eval), partner closely with engineering to productionize models, and lead end-to-end transformation of customer-facing voice and chat self-service experiences.