Senior Applied Scientist

Microsoft; City of Westminster; On-site; GBP 75,000 - 123,000; Full time

Job summary

Microsoft UK is seeking a Senior Applied Scientist to advance M365 Copilot Search and Chat quality. You will research, evaluate, and apply cutting-edge vector search and ML techniques, working with platform teams to scale evaluation and deployment.

You will mine data to improve retrieval quality, build expertise in NLP and embeddings, and collaborate with product groups across Microsoft to deliver high-impact research-driven solutions.

Qualifications

• Bachelor's Degree requirements with 4+ years related experience OR Master's with 2+ years OR Doctorate in relevant fields
• Equivalent experience accepted

Responsibilities

• Research and evaluate tools, technologies, and methods to improve M365 Copilot Chat and Search quality
• Build deep knowledge of M365 Copilot Search and consult with engineers and product teams
• Mine data to identify opportunities and evaluate models, mapping user journeys and communication insights
• Develop expertise in search relevance, NLP, data-driven analysis, and scalable, extensible solutions
• Build collaborative relationships across Microsoft and publish research where applicable

Skills

ML

NLP

Information retrieval

Python

PyTorch

Vector retrieval

Embeddings

LLMs

A/B testing

Education

Bachelor's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field

Master's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field

Doctorate in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field

Tools

Python

PyTorch

FAISS

Job description

As a Senior Applied Scientist , you will work alongside other scientists to solve problems that delight Copilot Search and Chat users. Examples include adapting state-of-the-art vector search algorithms to the enterprise domain, and applying advanced ML to improve the retrieval quality of business-critical information by jointly optimizing query understanding and the retrieval algorithm. You will also partner closely with our platform team to accelerate the evaluation of retrieval algorithms at scale. Microsoft's mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond.

Responsibilities

• Research and evaluate tools, technologies, and methods from the community that can improve the quality, performance, or efficiency of M365 Copilot Chat and Search, and apply them to deliver business impact.
• Build deep knowledge of the M365 Copilot Search service while staying current with industry trends and advances in applied ML. Consult with engineers and product teams to apply advanced concepts to search quality improvements.
• Mine data to identify opportunities to apply state-of-the-art algorithms that improve M365 Copilot search quality. Apply statistical analysis to map user journeys, evaluate the behavior of deployed models, validate assumptions about evaluation results, and communicate insights to the team.
• Develop expertise in search relevance, NLP, and data-driven analysis, along with the relevant research literature and techniques. Use this understanding to identify, adapt, or create research-backed solutions‑novel, data‑driven, scalable, and extensible‑that improve M365 Copilot Chat and Search quality.
• Build collaborative relationships with product and business groups across Microsoft, contributing expertise and technology that create business impact. This may include authoring papers, developing and maintaining internal tools and services, and publishing research.

Qualifications

• Bachelor's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 4+ years related experience
• OR Master's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 2+ year(s) related experience
• OR Doctorate in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field
• OR equivalent experience.

Other Requirements

Ability to meet Microsoft, customer and/or government security screening requirements are required for this role. These requirements include but are not limited to the following specialized security screenings: Microsoft Cloud Background Check: This position will be required to pass the Microsoft Cloud background check upon hire/transfer and every two years thereafter.

Experience and Skills

• Experience applying machine learning, NLP, or information retrieval techniques to search or recommendation problems.
• Experience using data analysis and offline/online evaluation to diagnose metrics, user journeys, model behavior and improve product quality.
• Applied ML engineering experience using Python and modern ML frameworks such as PyTorch.
• Hands‑on experience with dense/vector retrieval and text embeddings, including bi‑encoders, approximate nearest‑neighbor search, contrastive training, or hard‑negative training.
• Familiarity with information retrieval fundamentals and retrieval evaluation, including metrics such as recall@k and nDCG, offline evaluation pipelines, and interpretation of A/B test results.
• Experience fine‑tuning or adapting transformer or large language models for a specific domain, including domain adaptation, distillation, parameter‑efficient fine‑tuning, and curation of clean in‑domain training data.
• Solid applied ML engineering skills in Python and PyTorch, with experience running large‑scale training and evaluation jobs on cloud or GPU clusters.

Do you want to be part of a team that delivers innovative products and machine learning solutions to hundreds of millions of users across Microsoft every month? The Copilot Agent & Search Quality team is at the forefront of the core Copilot experiences across Microsoft products, including Copilot Chat and Search, helping users find the right information in their organization and accelerating their productivity.

Applied Sciences IC4 - The typical base pay range for this role across United Kingdom is £ 74,700.00 - £ 122,600.00 per year. Certain roles may be eligible for benefits and other compensation.