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Mitchell Naylor

Member of Technical Staff ยท Cohere

Post-training research for coding models.

About

Mitch Naylor is a machine learning and AI scientist with extensive experience in natural language processing (NLP), statistical modeling, and deep learning. Mitch currently works as a member of technical staff at Cohere, where he works on all things related to post-training LLMs for code. Mitch is also an author of Applied Causal Inference, released August 2023.

Mitch lives in Chattanooga, TN. Outside of work, he enjoys rock climbing, hiking, music, and traveling.

Experience

Cohere

Member of Technical Staff

July 2026 โ€“ Present

I am joining Cohere as a Member of Technical Staff on the post-training team for coding models. This includes experimentation on model training (RL and SFT), as well as the environments and infrastructure which make RL possible.

GitHub

Staff Applied Researcher

April 2024 โ€“ July 2026

I worked as a technical leader in GitHub Copilot's Applied Science team, leading small teams of applied researchers to execute on high-impact, cross-functional efforts to improve Copilot products. This included:

  • Post-training LLMs to improve model performance on high-priority applications, including leading efforts to use reinforcement learning (RL) for agentic tasks โ€” designing reward functions, training pipelines, and evaluation processes
  • Designing agentic systems to accomplish complex software engineering tasks, such as reviewing pull requests (see Copilot Code Review), and partnering with engineering and product teams to develop and improve early-stage products
  • Conducting A/B tests to quantify model improvements, and contributing to a culture of shipping quickly and rigorously
  • Mentoring junior team members through pairing and sharing knowledge of ML best practices, and acting as a key member of the hiring team for applied researchers โ€” designing technical interview material and assessing prospective team members

Azra AI

Lead Data Scientist

October 2019 โ€“ March 2024

At Azra AI, I operated as a "full-stack" data scientist, from collaborating with clinical stakeholders to leading research efforts on efficient attention mechanisms for Transformers and model pretraining.

  • Led research on efficient architectures for long-context NLP, implementing and adapting emerging methods (including MEGA architecture contribution to Hugging Face Transformers) for clinical NLP
  • Designed pretraining and domain-adaptation pipelines, producing language models optimized for deployment on resource-constrained hardware
  • Built and deployed clinical NLP models (NER, classification) identifying high-risk findings for 200k+ patients annually, enabling early detection and faster treatment
  • Drove technical strategy for ML product development โ€” evaluating cutting-edge research and rapidly prototyping novel architectures for production deployment, and collaborating with clinical stakeholders to ensure model accuracy and reliability met the high standards required for cancer detection workflows

Note: Azra AI spun out as a standalone company in January 2022, previously part of Digital Reasoning

Asurion

Data Scientist

March 2018 โ€“ October 2019

Applied methods from NLP, statistical inference, and operations research to a diverse set of business problems, communicating findings to audiences ranging from highly technical to C-level.

GEICO

Product Modeling Analyst III

June 2016 โ€“ March 2018

Built predictive models of customer behavior under various pricing scenarios and ran robust statistical analyses in support of the pricing department.

Publications & Open Source

Applied Causal Inference

Authored the book Applied Causal Inference, released August 2023.

Journal of Oncology Navigation and Survivorship, 2023

Using Machine Learning to Accelerate Identification of Pancreatic Incidentalomas

Interpretable ML in Healthcare (IMLH) at ICML, 2021

Quantifying Explainability in NLP and Analyzing Algorithms for Performance-Explainability Tradeoff

IEEE International Conference on Bioinformatics and Biomedicine (BIBM), 2021

PsychBERT: A Mental Health Language Model for Social Media Mental Health Behavioral Analysis

Transformers for Machine Learning: A Deep Dive

Code contributions for the textbook by Kamath, Graham & Emara (Chapman & Hall, 2022).

Explainable Artificial Intelligence: An Introduction to Interpretable Machine Learning

Code contributions for the textbook by Kamath & Liu (Springer, 2021).

Education

M.S. Analytics

Georgia Institute of Technology

Completed December 2020

B.S. Business Analytics

University of Tennessee

Completed May 2016