Ellis graduated from Boston Latin School and attended Harvard University, where he studied German literature and mathematics.
He pursued graduate study at the Courant Institute of Mathematical Sciences.
In 1972, he received his PhD from the New York University for his thesis Chapman-Eskog-Hilbert Expansion for Models of the Boltzmann Equation under the supervision of Henry McKean.
[2] In 1984, he improved a key result in large deviations theory originally due to Jürgen Gärtner, which is now known as Gärtner-Ellis Theorem.
[3][4] Ellis died of bile duct cancer in New York City on July 2, 2018, aged 71.