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Day Yi

Lecturer; Analytics Consultant

Day is an actuary by training and now runs a consulting practice focused on data technologies. His client list includes companies such as New York Life, Unilever, Morgan Stanley, and Bank of China. Prior to his consulting practice, he was a Senior Actuary at Memorial Sloan Kettering. He has also previously worked as an Actuarial Associate at Prudential, MetLife, Jefferson Pilot, and Genworth. 


Day’s passion for teaching has been a steady part of his work life. He has taught college-level math courses, trained corporate clients, and built his own online educational company. In 2021, he was selected as a finalist for Columbia’s Presidential Award for Outstanding Teaching. He has given talks at conferences and been invited to speak to various student organizations. Besides teaching, Day enjoys being a mentor to students looking to enter the data analytics profession.


  • M.S., New Jersey Institute of Technology
  • B.A., Johns Hopkins University