Please welcome Dr. Amy R. Ward to the ISE Department. Dr. Ward is a Professor of Data Sciences and Operations at the University of Southern California. She will discuss the problem that many classic models used to study scheduling problems do not incorporate customer impatience and how that assumption can lead to poor scheduling decisions.
As always refreshments are available in 428 Daniels Hall 30 minutes before the seminar begins.
The study of scheduling problems has a long history in the academic literature. However, many classic models used to study scheduling problems do not incorporate customer impatience. Furthermore, many of the ones that do assume the time a customer is willing to wait for service is exponentially distributed. The issue is that that assumption can lead to poor scheduling decisions.
Our objective is to study the interplay between customer impatience and scheduling decisions when managing heterogeneous customer classes. We do this in the context of a many server queue, and develop results in as general a framework as possible. First, we use the solution of an approximating diffusion control problem to propose and numerically evaluate a scheduling policy. Under certain conditions, we see a novel “U-shape” structure emerge. Second, we consider how to prove an asymptotic optimality result. For this, the first step is to understand fluid-scale behavior. That leads to an interesting closed-form non-linear relationship between the queue-length and the server effort allocation.
Amy R. Ward is Professor of Data Sciences and Operations in the Marshall School of Business at the University of Southern California (USC). She received her Ph.D. from Stanford University in 2001. Her research focuses on the approximation and control of systems in which uncertainty and variability are present, and cannot be ignored. Service systems are her main application area. She has over 25 journal publications. She received the Marshall Deans Award for Research Excellence in 2015. She is the chair of the Applied Probability Society (term 11/2016-6/2018) and the Service SIG Chair for the MSOM Society (term 6/2017-6/2019).
