Frederick Hillier (1936-2026)

 I never took a course from Fred Hillier when I was a PhD student in the Department of Operations Research at Stanford from 1971-73, but as an assistant professor at the University of Illinois from 1974 I taught undergraduate OR from the introductory OR textbook by Hillier and Lieberman.

Here's his Stanford obituary:

Influential textbook author Frederick S. Hillier dies at 89
Hillier’s work shaped operations research theory and practice at Stanford and beyond, with his textbooks introducing the field to generations of learners worldwide.

"Frederick S. Hillier, professor emeritus of operations research in Stanford Engineering’s Department of Management Science and Engineering, passed away on Jan. 9, 2026. He was 89.
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"Hillier was best known for co-authoring Introduction to Operations Research, first published in 1967. “His textbook played a major role in defining what operations research is,” said Peter W. Glynn, professor of management science and engineering at Stanford. “It helped people in adjacent fields understand what the field is and how it works.” 

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"When he arrived at Stanford, Hillier was assigned Gerald J. Lieberman as his freshman adviser. Lieberman introduced Hillier to the emerging field of operations research and became Hillier’s undergraduate mentor, doctoral advisor, department chair, and eventually his co-author.

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"Following Lieberman’s encouragement, Hillier stayed at Stanford for graduate school. He earned an MS in statistics in 1959 and a PhD in operations research in 1961. He joined the Stanford faculty as an assistant professor in the Department of Industrial Engineering that same year.

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"Hillier retired in 1996 and continued revising his textbooks into his late 80s. The 11th edition of Introduction to Operations Research was published in 2020, and he completed the manuscript for the 12th edition in 2023."