Jim Renegar, the Class of 1912 Professor of Engineering Emeritus, has retired.
Renegar has been on the faculty since 1987 and served as director from 2004 to 2009. In his research, Renegar focused on developing mathematical foundations for a variety of algorithmic issues pertaining to continuous optimization and to the numerical solution of systems of algebraic nonlinear equations. This included creating new families of algorithms possessing novel properties, and deepening our understanding of existing algorithms and modeling techniques.
At a celebration of Renegar’s career, David Williamson, director of the School of Operations Research and Information Engineering read the following tribute.
It’s my great privilege to say a few words in honor of Jim’s retirement this evening.
Cornell’s School of Operations Research and Information Science has long been known as a – or the – top institution in the world for optimization, and Jim has been one of the people who has made that reputation over the nearly 40 years that he has been on the faculty. He’s made amazing contributions to the literature in continuous optimization.
As many of you know, I lead a double life, wearing another hat over in the Department of Information Science. In that department, one of the highest words of praise that you can give an intellectual piece of work is to say that it is ‘generative,’ meaning that it creates a foundation for many, many other people to build upon; it creates room, it opens doors, and researchers can use it to do other things maybe not even realizing how much they are indebted to that original contribution.
That is a characterization of much of Jim’s work, but especially his work on interior point methods: It was one of a handful of papers that spawned a field with literally over a thousand papers, leading both to tremendous theoretical and practical innovation in efficient optimization algorithms for linear and convex optimization problems. For his contributions to this area and to others, Jim has been recognized with many honors, including being named a SIAM Fellow in 2017 and winning the 2018 Khachiyan Prize for Lifetime Achievement from the INFORMS Optimization Society.
Jim’s style of research is in some sense the opposite of the computer science conference style of research in which I was trained. While computer scientists are always trying frantically to make that one more incremental contribution in time for the next conference deadline, Jim’s style was more along the lines of the old Orson Welles’ Gallo tagline of ‘serving no wine before its time.’ He worked over long periods of time, writing singly-authored papers, making large contributions with elegance and depth. The papers were fewer but monumental and profound in their impact.
Jim’s contributions to the department and the area went well beyond his research contributions. Shortly after I arrived, he became director of the department and served for five years – one that, since that time, only Mark Lewis has matched, and I have no intention of duplicating. Jim oversaw significant changes to the department, including the creation of the Cornell Financial Engineering Manhattan, or CFEM, an outpost of the department in New York City, and the introduction of a third semester in the city for our financial engineering students, giving them important practical experience in the heart of the financial world. He was one of the founding members of the Society for Foundations of Computation Mathematics, serving for many years on its board of directors and in many of its organizational roles repeatedly.
Not only has Jim been an outstanding researcher and administrator, but an outstanding teacher as well. He has won the College of Engineering Teaching Excellence Award four times and was elected ‘Professor of the Year’ by the students in the department six times. Students praise him for helping them understand hard concepts, for caring for them, and for putting large amounts of time into how he presented course material. One student’s remarks are typical of the many students whom he taught:
“I think the main strength of the course is Professor Renegar’s lectures and lecture notes. He has managed to take a particularly difficult subject and make it seemingly easy. It’s no wonder he got the excellence in teaching award a couple years ago. I think he’s extremely dedicated to his students and it shows in his commitment to the class! He’s a great teacher and I am so happy I got to take this class with him. If I ever donated money to Cornell, it would be because of Professor Renegar, and I would gladly sponsor his research. He is brilliant and I really appreciated learning from his class each and every day.”
Finally, in an environment in which oversized accomplishments are often matched with oversized egos, that is not Jim at all. He is modest to the point of reticence; he could easily have had a multiday conference in his honor on retirement, celebrating his many achievements, but he wanted to have a beer together with a small number of friends and colleagues.
Jim, I remember you entering one faculty meeting as director and saying, “Welcome to the best operations research department anywhere.” You are a big part of what made it so. Congratulations on your retirement, and many, many thanks for your many contributions to the department.