My name is Roy and I'm a data scientist, machine learning engineer, and team leader in Houston, Texas, USA. I have built and led data science and machine learning teams at several companies. I am also the co-organizer of the Houston Data Analytics Meetup group and the founder of Zefs Data Science, where I do occasional consulting work related to data science and machine learning strategy and team planning.

I am the author of the in-progress series Zefs Guides, a series of little guides to machine learning and data science topics. The first book in the series, Zefs Guide to Deep Learning, is available now in paperback and ebook formats, as well as accompanying digital flashcards.

I'm also the author of Hiring Data Scientists and Machine Learning Engineers: A Practical Guide, a book I wrote drawing on my experience building data science and machine learning teams, and featuring interviews with experienced hiring managers from across the tech industry. It covers the entire process of hiring data scientists, MLE's, and related roles, from team planning, through hiring, to onboarding your new hires. You can purchase it now!

By training I am a physicist. My PhD focused primarily on Monte Carlo-based radiation simulations aimed at improving cancer treatments. Nowadays I focus on the broad application of computational data analysis, machine learning, and visualization, along with leading teams to do those things.

This site is home to some of my data projects, occasional blog posts, and links to my other web presences.