Richard E. Nance

July 22, 1940

Brief Biography

Nance Fellow Portrait

Richard E. Nance is a leader in computer simulation, having received the INFORMS Simulation Society’s Distinguished Service and Lifetime Professional Achievement Awards. Nance obtained his bachelors and masters degrees from North Carolina State University. In the classroom and meetings with his advisors, he developed a fascination with the term “simulation,” and sought a fuller understanding of the subject. Between the BS and MS degrees, he served for two years as a member of the management staff of Procter and Gamble.   Nance resumed his studies in 1964, focusing on computer simulation and gaming. His decision to seek a PhD in industrial engineering at  Purdue University was influenced by the requisite presence of strong programs in computer science and statistics,   His doctoral research involved the comparative study of control systems in libraries using models based on simulation constructs from industrial (later, “system”) dynamics.

After completing graduate study in 1968, Nance accepted a position with the Computer Sciences Center (combining operations research and computer science) at Southern Methodist University in Dallas. While continuing his research in simulation, he also pursued an interest in stochastic models for computer performance evaluation and computer communications networks with Narayan Bhat, a research partnership that continued for decades.  Concerned with the challenges in validating system dynamics models, Nance returned to the study of time flow mechanisms for discrete event simulation originally encountered in his master’s work.  In 1971, he showed that event scheduling, the widely used time flow mechanism in SIMSCRIPT and other languages in the U.S., did not produce the minimal execution time for all discrete event models.

Nance accepted appointment as Department Head of Computer Science at Virginia Tech in 1973, serving until 1979.  During that period, his interests broadened to include aspects of the modeling decisions that affected the time and state representations provided in the transition from the conceptual and more abstract view of the modeler to executable forms that were efficient in execution, amenable to verification and validation, and maintainable over an extended period of use.  Particularly interesting was the activity cycle diagram, quite simple in concept but widely used in the UK as the input to program generators – skeletal model structures that the modeler completed to affect an executable program in one of several language choices.  In 1979-80 Nance took a sabbatical to study at the Naval Surface Weapons Center in Dahlgren, Virginia and at Imperial College, London.  His work in the UK was supported by a UK Science Research Council Senior Research Fellowship that enabled travel to meet with a number of British researchers in simulation.  A product of this extended effort was an influential paper on the time and state relationships in simulation modeling that formed the cornerstone for his major contributions in simulation model development (or simulation support) environments .  His primary collaborators were Michael Overstreet, Osman Balci, and Ernest Page.

From 1970 until his retirement, Nance worked closely with the U.S. Navy.  In 1984 he was appointed director of the Systems Research Center, established by the Navy at Virginia Tech.  He held the RADM John Adolphus Dahlgren Chair in Naval Computing from 1988 until his retirement in 2004.

.In his later career, Nance has played a role in chronicling and reflecting upon the development of computer simulation. In 1996, he authored a chapter in History of Programming Languages - II on the history of discrete event simulation programming languages.  Six years later, he and Robert G. Sargent co-authored an article in Operations Research offering their perspectives on the evolution of simulation.

In addition to being a recipient of the Simulation Society awards, Nance holds the rare distinction of being a Fellow of both the Association of Computing Machinery (ACM) and the Institute for Operations Research and the Management Sciences (INFORMS). He was recognized for his long-standing editorial service in the establishment and advancement of computer simulation literature. On numerous occasions, Nance has been lauded for his contributions to the methodology and software environments that enable large-scale simulation model development.

Other Biographies

(2013) Simulation and software through 50 years: Richard E. Nance Bio. Hill R., Kim S. H., Pasupathy R., & Tolk A., eds. in Proceedings of the 2013 Winter Simulation Conference, 3. Association of Computing Machinery: Santa Barbara, CA. (link)

Virginia Tech College of Engineering. Department of Computer Science: Richard E. Nance. Accessed August 8, 2018. (link


North Carolina State University, BS 1962

North Carolina State University, MS 1966

Purdue University, PhD 1968 


Academic Affiliations
  • Purdue University
  • Brunel University
  • Imperial College of Science and Technology
  • North Carolina State University
  • Old Dominion University
  • Southern Methodist University
  • Stevens Institute of Technology
  • Virginia Polytechnic Institute and State University
Non-Academic Affiliations

Key Interests in OR/MS

  • Software Engineering

Oral Histories

Richard E. Nance (2013) Interview by Robert G. Sargent, January 24. North Carolina State University: Raleigh, NC. NCSU Computer Simulation Archive. Raleigh, North Carolina. (video)


Richard E. Nance Papers, MC 00283, Special Collections Research Center, North Carolina State University Libraries, Raleigh, NC. (link)

Awards and Honors

Science Research Council (UK) Senior Research Fellowship 1980

Simulation Society Distinguished Service Award 1987

Association for Computing Machinery Fellow 1996

Simulation Society Lifetime Professional Achievement Award 2007

Institute for Operations Research and the Management Sciences Fellow 2008

Selected Publications

Nance R. E.  (1971) On time flow mechanisms for discrete system simulation. Management Science, 18(1): 59-73.

Bhat U.N. & Nance R.E. (1971) Busy period analysis of a time-sharing system modeled as a semi-Markov process. Journal of the Association for Computing Machinery, 18(2): 221-238,

Nance R.E. & Bhat U.N. (1979) An evaluation of CPU efficiency under dynamic quantum allocation. Journal of the Association for Computing Machinery, 26(4): 761-778.

Nance R. E. (1981) The time and state relationships in simulation modeling. Communications of the ACM, 24(4): 173-179.

Nance R. E. & Overstreet C. M. (1985) A specification language to assist in analysis of discrete event simulation models. Communications of the ACM, 28(2): 190-201.

Nance R. E. (1994) The conical methodology and the evolution of simulation model development. Balci O., ed. in Annals of Operations Research, 53: 1-45.

Nance R. E. (1996). A history of discrete event simulation programming languages. Bergin Jr T. J. & Gibson Jr. R. G., eds. in History of Programming Languages - II,  369-427. American Association of Computing Machinery: New York.

Nance R.E., Overstreet C. M. & Page E. H. (1999) Redundancy in model specification for discrete event simulation. ACM Transactions on Modeling and Computer Simulation, 9(3): 254-281.

Nance R. E. & Sargent R. G. (2002) Perspectives on the evolution of simulation. Operations Research, 50(1): 161-172. (link

Nance R. E. &  Arthur  J. D. (2002) Managing Software Quality: A Measurement Framework for Assessment and Prediction. Springer-Verlag: London.