Mark E. Lewis, Professor
Mark-Dec-2015 

Cornell University
School of Operations Research and Information Engineering

Rhodes Hall
Ithaca, NY 14853
phone 607.255.0757
fax 607.255.9129
email
mark.lewis 'at' cornell 'dot' edu


I am a faculty member in the
 School of Operations Research and Information Engineering at Cornell University. My undergraduate degrees are in Mathematics and Political Science from Eckerd College . I earned a Master's Degree in Theoretical Statistics from the Florida State University  and a PhD in Industrial Engineering from the Georgia Institute of Technology . After completing my Ph.D., I spent a year at the University of British Columbia as a postdoctoral fellow in the Centre for Operations Excellence with Martin Puterman.  I spent six years in the Department of Industrial and Operations Engineering at the University of Michigan in Ann Arbor, Michigan before arriving at Cornell University in the School of Operations Research and Information Engineering.  I am an avid sports fan and I love to watch football (did I mention I went to Florida State?) and play basketball.

Link To My Curriculum Vitae

Current Research
My research interests are in Stochastic Processes with an emphasis on queueing theory. My thesis work (albeit more than 20 years ago) was in this area with Professor Hayriye Ayhan and Professor Robert (Bob) D. Foley. We used Markov Decision Processes to uncover some new ideas in trunk reservation and bias optimality. I also spent time at the University of British Columbia in the Centre for Operations Excellence as a postdoctoral fellow working with Martin L. Puterman. We explained implicit discounting in bias optimality and again related it to controlled queueing systems. Most recently, I have gotten interested in parallel processing and how resources are allocated dynamically in such systems. This includes if systems are flexible enough to run servers on and off (to save energy in say, server farms) or to repair deteriorated systems (in manufacturing). There is also some work on fundamental advances in average cost Markov decision processes with Eugene Feinberg. Some of this work is detailed in the papers below.

Publications 

1.        Cory Girard and Mark E. Lewis, “Constrained Optimization of a Finite Number of Parallel Stations”,  [Abstract or full paper K-class-constrained.pdf]

2.        Jefferson Huang, Douglas G. Down, Mark E. Lewis, and Cheng-Hung Wu, “Dynamically scheduling and maintaining a flexible server”, under review [Abstract or full paper sched-repair-submission.pdf]

3.        Cory Girard, Linda V. Green, Mark E. Lewis and Jingui Xie, “A Constrained Optimization Problem for a Two-Class Queueing Model”, under review [Abstract or full paper constrained-queue.pdf]

4.        Pamela Badian-Pessot, Douglas G. Down, and Mark E. Lewis, “Optimal control policies for an M/M/1 queue with a removable server and dynamic service rates”, to appear in Probability in the Engineering and Informational Sciences, 2019. [Abstract or full paper removable-dynamic.pdf]

5.        Gabriel Zayas-Cabán, Jingui Xie, Linda V. Green and Mark E. Lewis, “Policies for Physician Allocation to Triage and Treatment in Emergency Departments”, to appear in IIE Transactions on Healthcare Systems Engineering, 2019. [Abstract or full paper: K-level.pdf]

6.        Gabriel Zayas-Cabán and Mark E. Lewis, “Admission Control in a Two Class Loss System with Periodically Varying Parameters and Abandonments”, to appear in Queueing Systems: Theory and Applications, 2019. [Abstract or full paper: periodic-abandon.pdf]

7.        Mark E. Lewis and Anand Paul, “Uniform turnpike theorems for finite Markov decision processes”, to appear in Mathematics of Operations Research, 2019 [Abstract or full paper: turnpike.pdf]

8.        Eugene Feinberg and Mark E. Lewis, “On the Convergence of Optimal Actions for Markov Decision Processes and the Optimality of (s,S) Policies for Inventory Control”, to appear in Naval Research Logistics, 2018. [Abstract or full paper: inventory.pdf]

9.        Kenneth C. Chong, Shane G. Henderson and Mark E. Lewis, “Two-Class Routing with Admission Control and Strict Priorities”, in Probability in the Engineering and Informational Sciences, 2018. [Abstract or full paper: strict-priority.pdf] (online appendix)

10.   Gabriel Zayas-Cabán, Jingui Xie, Linda V. Green and Mark E. Lewis, “Dynamic control of a tandem system with abandonments”, Queueing Systems: Theory and Applications, Vol. 84(3), 279–293, December 2016. [Abstract or full paper: Treatment-triage.pdf ] (online appendix)

11.   Kenneth C. Chong, Shane G. Henderson and Mark E. Lewis, “The Vehicle Mix Decision in Emergency Medical Service Systems”, Manufacturing & Service Operations Management, Vol. 18(3), 347-360. [Abstract or full paper: vehiclemix.pdf]

12.   Ravi Kumar, Mark E. Lewis and Huseyin Topaloglu, “Dynamic Service Rate Control for a Single Server Queue with Markov Modulated Arrivals”, Naval Research Logistics, Vol. 60(8), 661–677, December 2013. This material is based upon work supported by the National Science Foundation under Grant Nos. CMMI-0900460 and CMMI-0826255. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: Markov-modulated.pdf].

13.   Gabriel Zayas-Cabán, Mark E. Lewis, Matthew Olson and Samuel Schmitz, “Emergency Medical Service Allocation in Response to Large Scale Events”, IIE Transactions on Healthcare Systems Engineering, Vol. 3(1), 57 – 68, January 2013. [Abstract or full paper: EMS-Response.pdf].

14.   Hyun-soo Ahn and Mark E. Lewis, “Flexible Server Allocation and Customer Routing Policies for Two Parallel Queues when Service Rates are not Additive”, Operations Research, Vol. 61(2), 344 – 358, April 2013. This material is based upon work supported by the National Science Foundation under Grant Nos. CMMI-0900460 and CMMI-0826255. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: alloc-route-final.pdf].

15.   Douglas G. Down, Ger Koole and Mark E. Lewis, "Dynamic Control of a Single Server System with Abandonments", Queueing Systems: Theory and Applications, Vol. 67(1), January 2011. This material is based upon work supported by the National Science Foundation under Grant Nos. CMMI-0900460 and CMMI-0826255. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: abandon-final.pdf].

16.   Luz A. Caudillo-Fuentes, David L. Kaufman and Mark E. Lewis, "A Simple Heuristic for Load Balancing in Parallel Processing Networks with Highly Variable Service Time Distributions”, Queueing Systems: Theory and Applications, Vol. 64(2), 145-165, February 2010. The original publication is available at www.springerlink.com. This material is based upon work supported by the National Science Foundation under Grant Nos. CMMI-0540808 and CMMI-0826255. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: heavy-tail-questa-final.pdf ].

17.   Douglas G. Down and Mark E. Lewis, "The N-Network Model with Upgrades", Probability and the Engineering and Informational Sciences, Vol. 24(2), 171-200, 2010. This material is based upon work supported by the National Science Foundation under Grant Nos. CMMI-0540808 and CMMI-0826255. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: N-network-up.pdf].

18.   Cheng-Hung Wu, Douglas G. Down and Mark E. Lewis, "Heuristics for Allocation of Reconfigurable Resources in a Serial Line with Reliability Considerations", IIE Transactions, Vol. 40(6), 595-611, June 2008. (also featured in IE Magazine, June 2008, p. 54-5). [ie-magazine-feature.pdf] This material is based upon work supported by the National Science Foundation under Grant No. CMMI-0540808. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: heuristic-wu.pdf].

19.   David Kaufman and Mark E. Lewis, "Machine Maintenance with Workload Considerations", Naval Research Logistics, Vol. 54(7), 750-766, 2007. This material is based upon work supported by the National Science Foundation under Grant No. CMMI-0540808. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: reliability.pdf]. 

20.   Eugene A. Feinberg and Mark E. Lewis, "Optimality Inequalities for Average Cost Markov Decision Processes and the Stochastic Cash Balance Problem", Mathematics of Operations ResearchVol. 32(4), 769-783, 2007. This material is based upon work supported by the National Science Foundation under Grant No. CMMI-0540808. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: mdp-cash-balance.pdf]

21.   Cheng-Hung Wu, Mark E. Lewis and Michael Veatch, "Dynamic Allocation of Reconfigurable Resources in a Two-Stage Tandem Queueing System with Reliability Considerations", IEEE Transactions on Automatic Control, Vol. 51(2), 309-314, 2006. This research was supported in part by the NSF grant DMI-0132811 and by the NSF Engineering Research Center for Reconfigurable Manufacturing Systems part of the Engineering Research Centers Program of the National Science Foundation under NSF Award Number EEC 95-29125. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect those of the National Science Foundation. [Abstract or full paper: reconfig.pdf]

22.   Douglas G. Down and Mark E. Lewis, "Dynamic Load Balancing in Parallel Queueing Systems: Stability and Optimal Control", The European Journal of Operational Research,  Vol. 168(2), 509-519, 2006. The original publication is available online at www.sciencedirect.com. This material is based upon work supported by the National Science Foundation under Grant No. DMI-0132811. [Abstract or full paper: load.pdf 

23.   David L. Kaufman, Hyun-soo Ahn, and Mark E. Lewis, "On the Introduction of an Agile, Temporary Workforce into a Tandem Queueing System", Queueing Systems: Theory and Applications, Vol. 51(1-2), 135-171, 2005. The original publication is available at www.springerlink.com. This material is based upon work supported by the National Science Foundation under Grant No. DMI-0132811. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: flex-temp.pdf

24.   Seongmoon Kim, Mark E. Lewis, and Chelsea C. White III, "State Space Reduction for Non-stationary Stochastic Shortest Path Problems with Real-Time Traffic Information", IEEE Transactions on Intelligent Transportation Systems, Vol. 6(3), 273-284, 2005. [Abstract or full paper: reduction.pdf

25.   Seongmoon Kim, Mark E. Lewis, and Chelsea C. White III, "Optimal Vehicle Routing with Real-Time Traffic Information", IEEE Transactions on Intelligent Transportation Systems, Vol. 6(2), 178-188, 2005. [Abstract or full paper: real-time.pdf]

26.   Eugene A. Feinberg and Mark E. Lewis, "Optimality of Four-Threshold Policies in Inventory Systems with Customer Returns and Borrowing/Storage Options", Probability in the Engineering and Informational Sciences, Vol. 19(1) 45-71, 2005. [Abstract or full paper: borrow.pdf 

27.   Seunghwan Yoon and Mark E. Lewis, "Optimal Pricing and Admission Control in a Queueing System with Periodically Varying Parameters", Queueing Systems: Theory and Applications, Vol. 47(3), 177-199, 2004. The original publication is available at www.springerlink.com. This material is based upon work supported by the National Science Foundation under Grant No. DMI-9908321. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: congestion_control.pdf ]

28.   Jason H. Goto, Mark E. Lewis, and Martin L. Puterman, "Coffee, Tea, or ...?: A Markov Decision Process Model for Airline Meal Provisioning". Transportation Science, Vol. 38 (1), 107-118, 2004. [Abstract or full paper: canadian_air.pdf 

29.   William L. Cooper, Shane G. Henderson, and Mark E. Lewis, "Convergence of Simulation-Based Policy Iteration", Probability in the Engineering and Informational Sciences, Vol. 17(2), 213-234, 2003. This material is based upon work supported by the National Science Foundation under Grant No. DMI-9908321. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: csbpi.pdf 

30.   Hyun-soo Ahn, Izak Duenyas, and Mark E. Lewis, "The Optimal Control of a Two-Stage Tandem Queueing System with Flexible Servers", Probability in the Engineering and Informational Sciences, Vol. 16(4), 453-469, 2002. [Abstract or full paper: flex.pdf 

31.   Mark E. Lewis, Hayriye Ayhan, and Robert D. Foley, "Bias Optimal Admission Policies for a Nonstationary Multiclass Queueing System", Journal of Applied Probability, Vol. 39(1), 20-37, 2002. This material is based upon work supported by the National Science Foundation under Grant No. DMI-9908321. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: nonstat.pdf

32.   Mark E. Lewis and Martin L. Puterman, "Bias Optimality". In The Handbook of Markov Decision Processes: Methods and Applications. Edited by Eugene Feinberg and Adam Shwartz. Kluwer, 89-111.  2001.  [Abstract or whole chapter: chapter.pdf 

33.   Mark E. Lewis, "Average Optimal Policies in a Controlled Queueing System with Dual Admission Control", Journal of Applied Probability , Vol. 38(2), 369-385, 2001. [Abstract or full paper: dual_ad.pdf

34.   W.S. Vincent Wong, Mark E. Lewis, and Victor C.M. Leung, "Stochastic Control of Path Optimization for Inter-Switch Handoffs in Wireless ATM Networks", IEEE/ACM Transactions on Networking, Vol. 9(3), 336-350, 2001. [Abstract or full paper: handoffs.pdf ]

35.   Mark E. Lewis and Martin L. Puterman, "A Probabilistic Analysis of Bias Optimality in Unichain Markov Decision Processes",  IEEE Transactions on Automatic Control, Vol. 46(1), 96-100, 2001.  This material is based upon work supported by the National Science Foundation under Grant No. DMI-9908321. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). [Abstract or full paper: bias2.pdf ]

36.   Mark E. Lewis and Martin L. Puterman, "A Note on Bias Optimality in Controlled Queueing Systems". The Journal of Applied Probability , Vol. 37(1), 300-305, 2000. [Abstract or full paper: biasnote.pdf 

37.   Mark E. Lewis, Hayriye Ayhan, and Robert D. Foley "Bias Optimality in a Queue with Admission Control". Probability in the Engineering and Informational Sciences , Vol. 13(3), 309-327, 1999.  [abstract or full paper: bias1.pdf ]

Back to Top

Classes Taught

·         ORIE 561: Queueing Theory

·         ORIE 6570: Stochastic Dynamic Programming

·         ORIE 6500: Applied Stochastic Processes

·         ORIE 6510: Probability Theory

·         ORIE 3510: Introductory Engineering Stochastic Processes

Other Links of Interest

Center for Applied Probability at Columbia 
INFORMS Applied Probability Society 
  
 

Back to Top

Sports Links

The Official Web Site of the NBA 
ESPNET Sportzone 
  
 

Back to Top

African-American Interests

INFORMS Minority Issues Forum 
The Universal Black Pages
Mathematicians of the African Diaspora

Back to Top