Bruce Hajek

The citation for the 2015 ACM SIGMETRICS Achievement Award says,

In 2015, Hajek collaborated with Cambridge University Press to publish as a book his course notes for his Random Processes course, ECE 534, at UIUC. The book is titled Random Processes for Engineers. He is also a co-author on the second edition of a more advanced book, Eugene Wong's Stochastic Processes in Engineering Systems (Springer, 1985).

From 1990 to 1993, Hajek served as the editor-in-chief for the IEEE Transactions on Information Theory. In 1995, he served as the president of the IEEE Information Theory Society. He has mentored 18 PhD students, including IBM CEO Arvind Krishna.

Bruce Hajek's PhD dissertation, titled Stochastic Integration, Markov Property and Measure Transformation of Random Fields, studied random fields of three types: continuous-parameter Markov random fields, continuous-parameter random fields admitting stochastic-integral representations, and random fields "arising from transformations of absolutely continuous measures". This work on random fields has been recognized by others. In 1987, Hajek and Toby Berger showed that, under weak assumptions, a Markov random field whose entries take values in a finite-order field (F,+,·) can be written as a component-wise sum of two independent random fields with F-valued components, with one of these two random fields being independent and identically distributed according to a nondegenerate probability measure.

Since 1986, he has been a recurring visitor at Cambridge University. In the 2009-2010 academic year, he was appointed a Rothschild Distinguished Visiting Fellow at the Isaac Newton Institute for Mathematical Sciences at Cambridge.

Hajek's work has significantly furthered the integration of computers and communications systems. His many papers have taken the chaotic field of communication networking and given it a coherence and conceptual structure that it previously lacked. In the early 1980s, he led research that proved the stability of dynamically controlled ALOHA multiple access. He and his students also developed algorithms for dynamic routing and transmission scheduling. These innovations showed that determinism in service time minimizes waiting time in network queues. In relation to these achievements, he was inducted to the National Academy of Engineering in 1999 "for contributions to stochastic systems, communication networks, and control". In 2003, he received the IEEE Kobayashi Award "for the application of stochastic and probabilistic theory to improved understanding of computer-network behavior, particularly, the modeling and performance optimization of multiple-access channels."

Bruce Hajek attended Willowbrook High School in Villa Park, Illinois. In 1973, he won the USA Mathematical Olympiad. In the same year, he graduated from high school. He entered the University of Illinois at Urbana-Champaign (UIUC) to study computer science, but later he switched his major to mathematics. After working in Summer 1975 at Brookhaven National Laboratory with Herbert Robbins, he graduated in 1976 with a BS in mathematics from UIUC and received an NSF Graduate Research Fellowship. He completed his MS degree in electrical engineering in 1977, again from UIUC, and then took his Fellowship to UC Berkeley, where he received his PhD in 1979 under Eugene Wong. The same year, he returned to the department of UIUC in Electrical & Computer Engineering, starting as an assistant professor and then becoming an associate professor (1982) and then a professor (1985). He was named the Leonard C. and Mary Lou Hoeft Chair in Engineering in 2006.