Halo! I'm Lei Ma. I am a physicist transformed data scientist based in Cologne, Germany. I am a theory-centric data scientist with well-trained engineering skills. I regularly organize online discussion groups to keep track of the frontier of machine learning. As for my engineering skillset, I worked on data warehouses and data lakes, model building, model deployment, and machine learning API for production. Nevertheless, my specialty is probability estimation in marketplaces which is easily generalized to other real-world problems.

Trained as a theorist, I embrace the exploration of collective intelligence and foster better collaborations in our society. Developing a career, I am currently working on marketplaces for logistics. By optimizing marketplaces using machine learning, we are building a more efficient and environmentally friendly future. In general, I am focusing on machine learning to improve our society and people's lives.

I am a maker. I've built a bunch of fun stuff in my free time to make people happy, most of which are open source as I am deeply attached to philosophy of open source. I am also an active reviewer of the Journal of Open Source Software.