Informs Annual Meeting 2017

TC15

INFORMS Houston – 2017

TC15

5 - An Election Game Based on Discretization of the Hotelling - Downs Model Timothy Murray, Graduate Student, University of Illinois, Urbana-Champaign, Urbana, IL, 61801, United States, tsmurra2@illinois.edu We present a discretized version of the Hotelling-Downs election game based on centroidal clustering of opinion polls. We show that it can be modeled as a congestion game, addressing the common issues of non-independent voter opinions and non-existence of a pure Nash equilibrium (PNE) when there are more than two candidates. Furthermore, we show that a PNE still exists when a non-shared penalty is added to each edge in the congestion game which can be used to model the cost of running a campaign. Finally, we provide a quadratic time algorithm for computing a PNE. 6 - Game Theoretic Modeling of Water Energy Nexus in the Presence of Competition Between Interdependent Firms Nabeel Hamoud, PhD Student, University of Wisconsin- Milwaukee, P.O. Box 413, Milwaukee, WI, 53201, United States, nmhamoud@uwm.edu, Jaejin Jang A game theoretic model of the Water-Energy Nexus is introduced to find the equilibrium of the water and electricity markets, when some of the output of a firm in one market (e.g. water market) is an input of another firm in a different market (e.g. electricity market) and vice versa. The firms make their decisions of the quantity to produce simultaneously. The result shows that market power is practiced and output is withheld when less players exists. It also shows that technology efficiency allows a player to capture more market share. It also increases the output of the firm, the total output of the industry and the output of the cross industry; hence reducing the market prices of the two goods. 332D Robust and Stochastic Optimization in Healthcare Sponsored: Manufacturing & Service Oper Mgmt, Healthcare Operations Sponsored Session Chair: Chaithanya Bandi, Northwestern University, Evanston, IL, 60208, United States, c-bandi@kellogg.northwestern.edu 1 - Design of Patient Flows via Robust Analysis of Fork-join Queues Chaithanya Bandi, 2001 Sheridan Road, Suite 566, Evanston, IL, 60208, United States, chaitu1287@gmail.com We consider the patient flow design in hospitals and model them using fork-join queues. Using robust queueing theory approaches, we provide tractable solutions. 2 - Ambulance Emergency Response Optimization in Developing Urban Centres Justin James Boutilier, University of Toronto, 532 Palmerston Boulevard, Apartment 6, Toronto, ON, M6G 2P5, Canada, j.boutilier@mail.utoronto.ca, Timothy Chan Time sensitive medical emergencies are a major health concern comprising one third of all deaths in low and middle income countries (LMICs). Despite evidence that ambulance services can save lives, poor access and availability of emergency medical care in LMICs continues to be a widespread problem. In this paper, we develop a novel ambulance location-routing model, tailored to address the challenges faced by urban areas in LMICs. We use extensive field data from Dhaka, the capital of Bangladesh and one of the most densely populated cities on earth, to apply our modelling framework. 3 - Robust Multi-period Regional Capacity, Location, and Access of Rural Cardiovascular Service under Uncertainty Dominic Johannes Breuer, Healthcare Systems Engineering Institute, Boston, MA, 02119, United States, dbreuer@coe.neu.edu, Nadia Lahrichi, Mohit Shukla, James C. Benneyan Timely access to cardiovascular services in rural areas is difficult to ensure due to long wait times, travel distance, and practice capacity restrictions. A robust multi- period model is developed to determine long-term locations, staffing, and assignment of patients with heterogeneous care needs under uncertainty. The objective is to improve access by minimizing patients’ travel distance, out-of- network referrals, and costs. The models are tested with a large health system in Maine. The model has important implications on existing and rapidly expanding health systems to aid their decisions related to care allocation. TC14

332E Procurement Mechanisms Sponsored: Manufacturing & Service Oper Mgmt, Supply Chain Sponsored Session Chair: Mili Mehrotra, University of Minnesota, Minneapolis, MN, 55455, United States, milim@umn.edu Co-Chair: Tharanga Kumudini Rajapakshe, University of Florida, Manmohan Aseri, University of Texas-Dallas, 2200 Waterview Parkway, Apt 1738, Richardson, TX, 75080, United States, mxa113030@utdallas.edu, Milind Dawande, Ganesh Janakiraman, Vijay S.Mookerjee A mobile-promotion platform enables advertisers to launch their personalized mobile advertising campaigns. The platform bids on behalf of dynamically- arriving campaigns to procure impressions at an ad exchange. We offer an effective rolling-horizon procedure, with an attractive guarantee, in which the platform periodically re-computes its policy for the procurement of impressions. 2 - Sustaining a Good Impression: Mechanisms for Selling Impressions at Ad Exchanges Sameer Mehta, sameer.mehta@utdallas.edu, Milind Dawande, Ganesh Janakiraman, Vijay S.Mookerjee At mobile ad exchanges, impressions are sold to advertisers through an auction mechanism. The status quo mechanism selects a single ad for display over the lifetime of an impression. We argue that such a mechanism leads to allocative inefficiency. To address this efficiency loss, we consider mechanisms in which multiple ads can be displayed sequentially over the lifetime of an impression. We obtain an optimal mechanism for this setting. Our analysis reveals that on an aggregate level, the optimal mechanism is a win-win for the ad exchange and the advertisers. We also obtain a “socially-responsible” optimal mechanism that guarantees a higher surplus to the ad exchange and the advertisers in the long run. 3 - The Effect of Supply Flexibility on Price-only Contracts for Fixed-price Newsvendors Mehdi Hosseinabadi Farahani, PhD Student, The University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080- 3021, United States, mxh143930@utdallas.edu, Milind Dawande, Haresh B. Gurnani, Ganesh Janakiraman We analyze a contract in which a supplier, who is exposed to disruption risks, presents a wholesale price and a supply-flexibility parameter to a buyer facing the newsvendor problem. The supplier is allowed to deviate from the order quantity by at most the flexibility parameter. We find the optimal contract when the demand distribution has an increasing generalized failure rate and show that the order quantity under the supply-flexibility contract is higher than that under the price-only contract. Furthermore, the supply-flexibility contract improves the supply chain efficiency. More interestingly, profits of the supplier and the buyer both increase by introducing flexibility into the contract. 4 - Sourcing under Multiple Attributes: Cost-sharing Mechanisms Shivam Gupta, Texas State University, 601 University Drive, San Marcos, TX, 78666, United States, s_g515@txstate.edu, Milind Dawande, Ganesh Janakiraman, Shouqiang Wang We propose a simple cost-sharing mechanism for a principal procuring a product (or service for a project) under multidimensional information asymmetry on the agent’s cost and non-cost attributes. We establish its optimality/near-optimality under several special cases, and provide valuable insights into the nature of cost- sharing for its use in practice. Gainesville, FL, 32608, United States, tharanga@ufl.edu 1 - On the Real-time Procurement of Impressions by Mobile-promotion Platforms

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