Cooperation under Limits on Information Exchange and Actions

Abstract: Interaction between information/communication and control (with “control” interpreted in a broader context, including strategic decision making in teams and games) has been a dominating research topic for several decades. This interaction is in general a complex one because, viewed as separate decision units, each one could help the other to achieve an overall better performance: more information generally leads to better control performance, and a judicious use of control could improve the information content of transmitted messages. These dual roles are not always aligned, however, making the derivation of optimal solutions to team problems generally much more challenging than obtaining for example saddle-point solutions to similarly structured games. Regardless of these difficulties, which are inherent to stochastic decision problems with non-classical information, the common element in all these problems of cooperation has been to find a satisfactory answer to the question of “what to send”, or equivalently “how to shape the information/sensor and control signals” so as to collectively meet a targeted objective.

With the emergence of remote control applications, some nontraditional and nonstandard constraints have been imposed on designs, prompted by constraints on power usage and limits on available resources. The questions that are now being asked are not only “what to send”, but also “when to send”, given some limitations on the number and frequency of transmissions (which could include sensor signals, control signals, or communication between agents) and also given the unreliability of the transmission medium where the information on whether the signals sent have reached their intended destinations or not is at best only partially available.

Following a brief overview of the classical paradigm of “what to send” and “how to shape”, this talk will discuss a mathematical framework wherein also the question of “when to send” can be given a precise meaning and addressed along with the former. Solutions to these problems involve threshold-type policies with online dynamic scheduling and offline computation. This is a rich paradigm with relevance not only to control but also to multi-agent teams and games.

Biography: Tamer Başar is with the University of Illinois at Urbana-Champaign (UIUC), where he holds the positions of Interim Director, Beckman Institute for Advanced Science and Technology;  Swanlund Endowed Chair; Center for Advanced Study Professor of  Electrical and Computer Engineering;  Research Professor in the Coordinated Science Laboratory; and Research Professor  in the Information Trust Institute. He received the B.S.E.E. degree from Robert College, Istanbul, and the M.S., M.Phil, and Ph.D. degrees  from Yale University.  He joined UIUC in 1981 after holding positions at Harvard University and Marmara Research Institute (Turkey).  He has published extensively in systems, control, communications, and dynamic games, and has current research interests in modeling and control of communication networks; control over heterogeneous networks; estimation and control with limited sensing and transmission; resource allocation, management and pricing in networks; mobile and distributed computing; and security issues in computer networks.

Dr. Başar is currently the Editor-in-Chief of Automatica,  the Editor-in-Chief of  IEEE Expert Now, Editor of the Birkhäuser Series on Systems & Control,   Managing Editor  of the Annals of the International Society of Dynamic Games (ISDG), and  member of editorial and advisory boards of several international journals in control, wireless networks, and applied mathematics. He has received several awards and recognitions over the years, among which are the Medal of Science of Turkey (1993); Distinguished Member Award  (1993),  Axelby Outstanding  Paper Award (1995), and Bode Lecture Prize (2004) of the IEEE  Control Systems  Society (CSS);  Tau Beta Pi Drucker Eminent Faculty Award of UIUC (2004);  Quazza Medal (2005) and Outstanding Service Award (2005) of the International Federation of Automatic Control (IFAC);  Bellman Control Heritage Award (2006) of the American Automatic Control  Council (AACC); honorary doctorate (Doctor Honoris Causa) from Doguş University (Istanbul; 2007); and honorary professorship from Northeastern University (Shenyang; 2008). He is a member of the US National Academy of Engineering, a member of the European Academy of Sciences, a Fellow of IEEE, a Fellow of IFAC, a past president of CSS, the founding president of ISDG, and the current President-Elect of AACC.

Tamer Basar