Introduction to the Team

Expedia Technology teams partner with our Product teams to create innovative products, services, and tools to deliver high-quality experiences for travelers, partners, and our employees. A singular technology platform powered by data and machine learning provides secure, differentiated, and personalized experiences that drive loyalty and traveler satisfaction.

We are looking for a Principal Machine Learning Scientist to join our growing Travel Search & Discovery team. This Principal will lead the development and optimization of Expedia's Search & Recommendation AI models including natural language search, multi-modal search, Recommendations, and generative AI-based discovery. The ideal candidate for this position is a true deep learning expert who can develop effective AI solutions for search and recommendations. Innovation and developing cutting-edge technology as well as implementing industry-leading solutions are key responsibilities of this role. This is a rare opportunity to build foundational systems in a high-impact domain, backed by Expedia's AI-first vision.

In this role, you will:

• Drive the research, design, and deployment of advanced machine learning solutions for large-scale search and recommendation systems
• Architect hybrid multi-modal retrieval frameworks, combining text, image, and structured data to power relevant and diverse content discovery
• Develop and optimize multi-stage ranking pipelines, leveraging deep learning, generative retrieval, and other advanced algorithms to maximize relevance and engagement
• Lead efforts on intent understanding, utilizing user queries, behavioral signals, and context for superior search and recommendation accuracy
• Advance personalization strategies using embeddings, user-item modeling, and context-aware algorithms to tailor content to individual users
• Pioneer cutting-edge sequential recommender systems that account for evolving user preferences, session context, and temporal dynamics
• Design robust offline and online evaluation methodologies, including A/B testing, counterfactual estimation, and metric development
• Collaborate closely with cross-functional engineering and product teams to translate business needs into machine learning problems and production-ready solutions
• Mentor and guide a team of scientists, driving best-in-class research and deployment practices

Minimum Qualifications:

• PhD, or MS, in Computer Science, Machine Learning, Statistics, Engineering, or a related field; or equivalent professional experience
• 10+ years of related industry experience
• Experience building production-grade search, recommendation or personalization systems
• Strong understanding of intent understanding techniques, retrieval methods, deep learning for recommendations, reinforcement learning, and causal inference
• Proficiency in Python and ML frameworks such as TensorFlow, JAX, or PyTorch
• Experience with large-scale distributed systems and big data technologies (e.g., Spark, Hadoop)
• Familiarity with A/B testing and experimentation methodologies
• Ability to work with large-scale, real-world data with attention to bias, fairness, and privacy
• Excellent communication skills for both technical and non-technical audiences
• Demonstrated ability to mentor and technically lead research or engineering teams
• A passion for building user-centric AI products and a keen curiosity about advancing the state-of-the-art in search and recommendations

Preferred Qualifications:

• Experience in the travel or e-commerce industry
• Familiarity with cloud platforms (AWS, GCP, Azure)
• Publications in top-tier ML conferences or journals
• Contributions to open-source ML projects
• Experience in personalization systems
• Experience taking models from prototype to production in collaboration with Machine Learning Engineering teams

The total cash range for this position in Seattle is $224,000.00 to $313,500.00. Employees in this role have the potential to increase their pay up to $358,500.00, which is the top of the range, based on ongoing, demonstrated, and sustained performance in the role.The total cash range for this position in San Jose is $242,000.00 to $338,500.00. Employees in this role have the potential to increase their pay up to $387,000.00, which is the top of the range, based on ongoing, demonstrated, and sustained performance in the role.

Starting pay for this role will vary based on multiple factors, including location, available budget, and an individual's knowledge, skills, and experience. Pay ranges may be modified in the future.

Benefits and perks

Expedia Group offers benefits and perks designed to support employees and their families, including medical, dental, and vision coverage, paid time off, an Employee Assistance Program, wellness and travel reimbursement, travel discounts, and International Airlines Travel Agent Network (IATAN) membership. Learn more about life at Expedia Group at https://careers.expediagroup.com/life.