Dr.Ramesh Johari

Stanford University

 

Abstract:

We study a system where a service is shared by many identical customers; the service is provided by a single resource. As expected each customer experiences congestion, a negative externality, from the others' usage of the shared resource in our model. In addition, we assume each customer experiences a positive externality from others' usage; this is in contrast to prior literature that assumes a positive externality that depends only on the mere presence of other users. We consider two points of view in studying this model: the behavior of self-interested users who autonomously form a ``club'', and the behavior of a service manager. We first characterize the usage patterns of self-interested users, as well as the size of the club that self-interested users would form autonomously. We find that this club size is always smaller than that chosen by a service manager; however, somewhat surprisingly, usage in the autonomous club is always efficient. Next, we carry out an asymptotic analysis in the regime where the positive externality is increased without bound. We find that in this regime, the asymptotic behavior of the autonomous club can be quite different from that formed by a service manager: for example, the autonomous club may remain of finite size, even if the club formed by a service manager has infinitely many members. Joint work with Sunil Kumar (Stanford GSB).

 

 

Bio:

Ramesh Johari is an Assistant Professor at Stanford University, with a full-time appointment in the Department of Management Science and Engineering (MS&E), and courtesy appointments in the Departments of Computer Science (CS) and Electrical Engineering (EE). He is a member of the Operations Research group in MS&E, and the Information Systems Laboratory in EE. He is also a member of the advisory board of the Stanford Clean Slate Internet Program. He received an A.B. in Mathematics from Harvard (1998), a Certificate of Advanced Study in Mathematics from Cambridge (1999), and a Ph.D. in Electrical Engineering and Computer Science from MIT (2004). He is the recipient of a British Marshall Scholarship (1998), First Place in the INFORMS George E. Nicholson Student Paper Competition (2003), the George M. Sprowls Award for the best doctoral thesis in computer science at MIT (2004), Honorable Mention for the ACM Doctoral Dissertation Award (2004), the Okawa Foundation Research Grant (2005), the MS&E Graduate Teaching Award (2005), the INFORMS Telecommunications Section Doctoral Dissertation Award (2006), and the NSF CAREER Award (2007). He has served on the program committees of ACM EC (2007), ACM SIGCOMM (2006), IEEE Infocom (2007, 2008, 2009), and ACM SIGMETRICS (2008, 2009).

Heilmeier Hall

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