Principal Applied Scientist

About the role

As a Principal Applied Scientist, you’ll deliver mission-critical innovations that directly improve Copilot experiences. Your work will include:

• Adapting advanced vector search algorithms (e.g., FAISS, ANN, ScaNN) for enterprise-scale semantic retrieval.
• Improving classic and neural keyword search quality through deep language understanding.
• Designing and training relevance models, including LLM fine-tuning and learning-to-rank (LTR) approaches.
• Building robust evaluation pipelines using offline metrics and online A/B experimentation.
• Driving cross-org collaboration with platform partners, other applied science teams, and product teams across time zones.

This is a highly impactful role requiring a mix of technical depth and strategic execution to shape the next generation of AI-powered search experiences. The team fosters a culture driven by growth mindset, collaboration, and inclusive innovation, rooted in core values of respect, integrity, and accountability.

Responsibilities

• Drive end-to-end applied science projects: From ideation and design to implementation, experimentation, and shipping. Lead high-impact projects that improve Copilot Chat, Copilot Search, and BizChat experiences by identifying search and relevance gaps, formulating hypotheses, and delivering scalable solutions.
• Innovate with scientific rigor: Apply cutting-edge techniques in machine learning, natural language processing, and information retrieval to address real-world challenges at enterprise scale. Design novel approaches for improving retrieval, ranking, query understanding, and semantic search in Copilot systems.
• Document, share, and amplify learnings: Promote transparency and innovation by capturing experimental results, documenting methodology, and publishing internal learnings to enable broader impact across the organization.
• Translate business goals into scientific strategy: Partner with product and business stakeholders to align team efforts with high-priority objectives. Translate ambiguous product requirements into clear, data-driven, and technically feasible directions.
• Collaborate across organizations and time zones: Work cross-functionally with platform engineering teams, peer science orgs, and product managers to ensure alignment, resolve dependencies, and unblock progress. Serve as a key bridge between applied science innovation and product delivery.

Qualifications

Required Qualifications:

• Bachelor's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 8+ years related experience (e.g., statistics, predictive analytics, research).
• Master's Degree in the same fields AND 6+ years related experience.
• Doctorate in the same fields AND 5+ years related experience.
• OR equivalent experience.

Preferred Qualifications:

• Bachelor's, Master's, or Doctorate in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 8+ years related experience (e.g., statistics, predictive analytics, research).
• OR equivalent experience.
• 8+ years of industrial programming experience in modern languages such as Python, Java, C++, or C#, including production-level ML pipelines.
• Demonstrated expertise in data analysis at scale, including working with logs, telemetry, and large datasets to uncover behavioral patterns, build evaluation datasets, and derive insights.
• Familiarity with modern machine learning and deep learning frameworks such as PyTorch, TensorFlow, scikit-learn, and Hugging Face Transformers.
• Proven ability to collaborate across engineering, product, and science organizations and communicate technical details clearly to both technical and non-technical stakeholders.

Pay

The typical base pay range for this role across the U.S. is USD $142,800 - $274,800 per year. A different range applies to specific work locations, including the San Francisco Bay area and New York City metropolitan area, where the base pay range is USD $188,000 - $304,200 per year. Certain roles may be eligible for benefits and other compensation.