Robust Dual Dynamic Programming
础耻迟丑辞谤蝉:听Angelos Georghiou, Angelos Tsoukalas, Wolfram Wiesemann
Publication:聽Operations Research, Forthcoming
础产蝉迟谤补肠迟:听
Multi-stage robust optimization problems, where the decision maker can dynamically react to consecutively observed realizations of the uncertain problem parameters, pose formidable theoretical and computational challenges. As a result, the existing solution approaches for this problem class typically determine suboptimal solutions under restrictive assumptions. In this paper, we propose a robust dual dynamic programming (RDDP) scheme for multi-stage robust optimization problems. The RDDP scheme takes advantage of the decomposable nature of these problems by bounding the costs arising in the future stages through lower and upper cost to-go functions. For problems with uncertain technology matrices and/or constraint right-hand sides, our RDDP scheme determines an optimal solution in finite time. If also the objective function and/or the recourse matrices are uncertain, our method converges asymptotically (but deterministically) to an optimal solution. Our RDDP scheme does not require a relatively complete recourse, and it offers deterministic upper and lower bounds throughout the execution of the algorithm. We demonstrate the promising performance of our algorithm in a stylized inventory management problem.
The Effects of Analyst鈥怌ountry Institutions on Biased Research: Evidence from Target Prices
础耻迟丑辞谤蝉:听Mark T. Bradshaw, Alan G. Huang, Hongping Tan
Publication:聽Journal of Accounting Research, Forthcoming
础产蝉迟谤补肠迟:听
Prior research demonstrates that a strong institutional infrastructure in a country moderates self鈥恠erving behavior of market participants. Cross鈥恈ountry economic activities have increased significantly, presenting a research opportunity to examine the relative influence of local versus foreign institutional infrastructure on individual market participants. We utilize variation in analyst鈥恈ountry location relative to covered firm location to examine institutional determinants of optimism in analyst research. Focusing on target prices, where persistent optimism is well documented, we find that analysts domiciled in countries with stronger institutional infrastructures exhibit significantly attenuated target price optimism and more value鈥恟elevant target prices. Our results demonstrate the importance of domestic country鈥恖evel institutional factors in moderating self鈥恠erving behavior of market participants engaged in cross鈥恈ountry activities.
Optimizing Foreclosed Housing Acquisitions in Societal Response to Foreclosures
础耻迟丑辞谤蝉:听Senay Solak, Armagan Bayram, Mehmet Gumus,聽Yueran Zhuo
Publication: Operations Research, Forthcoming
Abstract:
A dramatic increase in U.S. mortgage foreclosures during and after the great economic recession of 2007-2009 had devastating impacts on the society and the economy. In response to such negative impacts, non-profit community development corporations (CDCs) throughout the U.S. utilize various resources, such as grants and lines of credit, in acquiring and redeveloping foreclosed housing units to support neighborhood stabilization and revitalization. Given that the cost of all such acquisitions far exceeds the resources accessible by these non-profit organizations, we identify socially optimal policies for CDCs in dynamically selecting foreclosed properties to target for potential acquisition as they become available over time. We evaluate our analytical results in a numerical study involving a CDC serving a major city in the U.S, and specify social return based thresholds defining selection decisions at different funding levels. We also find that for most foreclosed properties CDCs should not offer more than the asking price, and should typically consider overbidding only when the total available budget is low. Overall, comparisons of optimal policies with historical acquisition data suggest a potential improvement of around 20% in expected total impacts of the acquisitions on nearby property values. Considering a CDC with annual fund availability of $4 million for investment, this corresponds to an estimated additional value of around $280,000 for the society.
Synergistic, Antagonistic, and Asymmetric Media Interactions
础耻迟丑辞谤蝉:听Ceren Kolsarici, and Demetrios Vakratsas
Publication: Journal of Advertising, Vol. 47, No. 3, 2018
A top paper nomination for Professor Hewlin
Professor Patricia Hewlin鈥檚 co-authored article entitled, 鈥淗ow do callings relate to job performance? The role of organizational commitment and ideological contract fulfillment,鈥� was nominated by the editors of Human Relations as one of the top papers published in 2018.
Protecting positioning innovations: the emergence of non-traditional trademark registrations
础耻迟丑辞谤蝉:听S. Mishra, Demetrios Vakratsas, and A. V. Krasnikov
Publication: Marketing Letters, Vol. 29, No. 3, September 2018
Angelos Georghiou appointed Associate Editor of Energy Systems
Angelos Georghiou,聽Assistant Professor in Operations Management, was recently聽appointed Associate Editor of Energy Systems - Optimization, Modeling, Simulation, and Economic Aspects.
The journal Energy Systems presents mathematical programming, control, and economic approaches towards energy systems related topics, and is especially relevant in light of the major worldwide challenges confronting humanity in this century.
Winning at a Losing Game? Side-Effects of Perceived Tournament Promotion Incentives in Audit Firms
础耻迟丑辞谤蝉:听Jorien Pruijssers, Pursey Pmar Heugens and Hans J. Van Oosterhout
Publication: Journal of Business Ethics, Forthcoming
Abstract:
A Smart-City Scope of Operations Management
础耻迟丑辞谤蝉:听Wei Qi and Zuo-Jun Max Shen
Publication: Production and Operations Management, Forthcoming
Abstract:
We are entering an era of great expectations towards our cities. The vision of 鈥渟mart city鈥� has been pursued worldwide to transform urban habitats into superior efficiency, quality and sustainability. This phenomenon prompts us to ponder what role the scholars in operations management (OM) can assume. In this essay, we express our initial thoughts on expanding OM to the smart-city scope. We review smart-city initiatives of governments, industry, national laboratories and academia. We argue that the smart-city movement will transition from the tech-oriented stage to the decision-oriented stage. Hence, a smart city can be perceived as a system scope within which planning and operational decisions are orchestrated at the urban scale, reflective of multidimensional needs, and adaptive to massive data and innovation. The benefits of studying smart-city OM are manifold and significant: contributing to deeper understanding of smart cities by providing advanced analytical frameworks, pushing OM knowledge boundaries (such as data-driven decision making), and empowering the OM community to deliver much broader impacts than before. We discuss several research opportunities to embody these thoughts, in the interconnected contexts of smart buildings, smart grid, smart mobility and new retail. These opportunities arise from the increasing integration of systems and business models at the urban scale.
Alain Pinsonneault Awarded 2018 SSHRC Insight Grant
Congratulations to聽Alain Pinsonneault,聽Professor in Information Systems, awarded the聽2018 SSHRC Insight Grant聽鈥淭he impact of explorative and exploitive use of information technology on individual performance鈥�.
Jui Ramaprasad and Alain Pinsonneault awarded 2018 SSHRC Insight Grant
Congratulations to聽Jui Ramaprasad,聽Associate Professor of Information Systems, and Alain Pinsonneault, Professor of Information Systems, awarded the 2018 SSHRC Insight Grant聽鈥淓xamining Value Creation in the Digital Economy: A Platform Engagement Perspective鈥�.
Low Status Rejection: How Status Hierarchies Influence Negative Tie Formation
础耻迟丑辞谤蝉:听Brian Rubineau, Yisook Lim and Michael Neblo
Publication: Social Networks, Vol. 56, January 2019
Abstract:
Managing Rapid Change and Rapid-Growth in Emerging Industries
础耻迟丑辞谤蝉:听Hamid Etemad and Christian Keen
Publication:聽International Journal of Entrepreneurship and Small Business, Vol. 34, No. 4, 2018
Abstract:
Designing Risk鈥怉djusted Therapy for Patients with Hypertension
础耻迟丑辞谤蝉:听Manaf Zargoush, Mehmet Gumus, Vedat Verter,聽Stella S. Daskalopoulou
Publication: Production and Operations Management, Forthcoming
Abstract:
Limited guidance is available for providing patient鈥恠pecific care to hypertensive patients, although this chronic condition is the leading risk factor for cardiovascular diseases. To address this issue, we develop an analytical model that takes into account the most relevant risk factors including age, sex, blood pressure, diabetes status, smoking habits, and blood cholesterol. Using the Markov Decision Process framework, we develop a model to maximize expected quality鈥恆djusted life years, as well as characterize the optimal sequence and combination of antihypertensive medications. Assuming the physician uses the standard medication dose for each drug, and the patient fully adheres to the prescribed treatment regimen, we prove that optimal treatment policies exhibit a threshold structure. Our findings indicate that our recommended thresholds vary by age and other patient characteristics, for example (1) the optimal thresholds for all medication prescription are nonincreasing in age, and (2) the medications need to be prescribed at lower thresholds for males who smoke than for males who have diabetes. The improvements in quality鈥恆djusted life years associated with our model compare favorably with those obtained by following the British Hypertension Society's guideline, and the gains increase with the severity of risk factors. For instance, in both genders (although at different rates), diabetic patients gain more than non鈥恉iabetic patients. Our sensitivity analysis results indicate that the optimal thresholds decrease if the medications have lower side鈥恊ffects and vice versa.
Quality at the Source or at the End? Managing Supplier Quality Under Information Asymmetry
础耻迟丑辞谤蝉:听Mohammad E. Nikoofal, Mehmet Gumus
Publication: Manufacturing & Service Operations Management, Vol. 20, No. 3, Summer 2018
Abstract:
