Principal Applied Scientist

Microsoft Microsoft · Big Tech · Redmond, WA +2 · Applied Sciences

This Principal Applied Scientist role focuses on building and operating advanced ML systems for real-time fraud detection in a large advertising ecosystem. The role involves designing anomaly detection approaches, building cross-signal correlation frameworks, and developing next-generation ML models and low-latency pipelines. Key responsibilities include architecting scalable end-to-end solutions, ensuring system performance, resilience, and cost-efficiency, and providing technical leadership and mentorship. The work directly influences platform capabilities and requires applying advanced ML methods like anomaly detection and LLMs with clear evaluation frameworks.

What you'd actually do

  1. Independently lead and execute multiple high-impact fraud detection initiatives, turning ambiguous problems into measurable business outcomes.
  2. Develop practical, deployable machine learning (ML) solutions that operate reliably at production scale, balancing detection effectiveness, latency, resilience, operational complexity, and cost.
  3. Translate scientific insights into production impact through rigorous experimentation, validation, rollout, monitoring, and continuous optimization under real-world operating constraints.
  4. Apply advanced ML methods—including anomaly detection, cross-signal analysis, large language models (LLMs), and other modern AI techniques—with clear evaluation frameworks, robust tests, and success metrics to deliver reliable, scalable, production-ready solutions.
  5. Drive technical collaboration across science, engineering, ads, security, and privacy teams to operationalize research and deliver end-to-end fraud detection capabilities.

Skills

Required

  • Bachelor's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 6+ years related experience OR Master's Degree AND 4+ years related experience OR Doctorate AND 3+ years related experience OR equivalent experience.
  • Ability to meet Microsoft, customer and/or government security screening requirements.
  • Microsoft Cloud Background Check

Nice to have

  • Master's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 9+ years related experience OR Doctorate AND 6+ years related experience OR equivalent experience.
  • 5+ years experience creating publications (e.g., patents, libraries, peer-reviewed academic papers).
  • 2+ years experience presenting at conferences or other events in the outside research/industry community as an invited speaker.
  • 5+ years experience conducting research as part of a research program (in academic or industry settings).
  • 3+ years experience developing and deploying live production systems, as part of a product team.
  • 3+ years experience developing and deploying products or systems at multiple points in the product cycle from ideation to shipping.
  • Extensive industry experience delivering machine learning solutions to production, including technical leadership in complex, ambiguous problem spaces.
  • Proven track record architecting scalable ML systems and low-latency decision pipelines that operate reliably and cost-efficiently at web scale.
  • Deep expertise in several of the following areas: statistical machine learning, anomaly detection, fraud and risk modeling, deep learning, large-scale data mining, and causal inference.
  • Demonstrated ability to set technical direction

What the JD emphasized

  • lead the most complex and ambiguous fraud challenges
  • architect scalable solutions end to end
  • production reliability requirements
  • operate reliably at production scale
  • real-world operating constraints
  • clear evaluation frameworks
  • robust tests
  • success metrics
  • reliable, scalable, production-ready solutions
  • operationalize research
  • end-to-end fraud detection capabilities
  • responsible AI practices
  • high standards for quality, reliability, and governance

Other signals

  • real-time detection
  • massive scale
  • high-precision, high-recall detection
  • adapting continuously
  • sophisticated threat landscape
  • architect scalable solutions end to end
  • performant, resilient, and cost-efficient
  • production reliability requirements
  • advanced ML methods
  • anomaly detection
  • cross-signal correlation
  • large language models (LLMs)
  • low-latency pipelines
  • rigorous experimentation
  • validation
  • rollout
  • monitoring
  • continuous optimization
  • responsible AI practices