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A common problem encountered in paper-production facilities is that of allocating customer orders to machines so as to minimize the total cost of production. It can be formulated as a dual-angular integer program, with identical machines inducing symmetry. While the potential advantages of decomposing large mathematical programs into smaller subproblems have long been recognized, the solution of decomposable integer programs remains extremely difficult. Symmetry intensifies the difficulty. This paper develops an approach, based on the construction of tight subproblem bounds, to solve decomposable dual-angular integer programs and successfully applies it to solve the problem from the paper industry. This method is of particular interest as it significantly reduces the impact of symmetry.

This paper describes a decision support system for paper production scheduling. This is the first system to provide an integrated solution to paper production scheduling and to consider interactions between different stages of the manufacturing and distribution process. Using a multicriteria optimization approach, the system generates multiple enterprisewide schedules to reveal tradeoffs between the multiple, often competing, objectives. The large portfolio of algorithms used by the system is embedded in an agent-based decision support framework, called Asynchronous Team (A-Team). Successful implementations of the system in several paper mills in North America have resulted in significant savings and improved customer satisfaction.

It is possible to distinguish seven process categories among OR/MS research strategies: ripple, embedding, bridging, transfer of technology, creative application, structuring, and statistical modeling. To examine how often OR/MS workers use these processes, this paper analyzes as a sample the contents of the papers in the 1992 Issues of Operations Research, Management Science, and Interfaces. It finds that the ripple process is dominantly used in theoretical research and the transfer-of-technology process is the one most frequently used in true applications. The paper also sets forth the full spectrum of results for all seven processes in the 1992 sample, and reaches some conclusions with possible implications for the future of OR/MS.

The costs, benefits and strategic role of intermediate echelons in distribution networks are not well understood in many industries. This paper describes a study of such multilevel systems in the industrial paper and plastics industry. We quantify the impact of redistributors, who buy products from manufacturers and sell them exclusively to other distributors. The methodology was applied to an industry-wide study. We derived statistics based on optimal distributor policies for channel choice and stock control. Based on our analysis, we found that effective use of redistribution, in conjunction with these policies, has the potential to generate savings of $446 million for the industry.

We use the models of cognitive psychology and the early literature on linear programming models to understand how experts organize their thinking about models. We show that several different patterns appear in the way models are related to each other. This paper also is a kind of cognitive history of the formulation of linear programming models in the first decade after the invention of the field.

Ackoff has decried the “devolution” of OR/MS, Corbett and Van Wassenhove have spoken of its “natural drift,” and a sociologist has described its “regression” as typifying that of other learned professions. To shed light on these views, we undertook a detailed survey of a segment of the OR/MS literature, with particular focus on the space in flagship journals devoted to theory on the one hand and applications on the other. While the literature of OR/MS contains many articles and texts with the word application in the title and the word data in the text, the definitions and uses of these terms are not precise. The claimed applications differ in degree and the actual data differ in kind. To encompass these different meanings we used a five-point scale to classify articles in the 1962 and 1992 volumes of Operations Research and Management Science and the 1972 and 1992 volumes of Interfaces. The resulting statistical analyses shed considerable light on the direction that OR/MS is taking and raise questions about its appropriateness. Finally, the paper raises fundamental questions about the direction that OR/MS should take and the roles that its journals should play in pursuing this direction.

A effective way to improve time-sensitive service systems is to reduce the right tail of the customer waiting-time distribution. We have instituted the following process at Operations Research that aims to reduce the right tail of the review-time distribution for submitted papers. 1. After a newly submitted paper has been with an Area Editor for 4 months, the Managing Editor contacts the Area Editor to get a status report. If the paper has not been processed by the 5-month mark, then the Managing Editor contacts the Associate Editor to get a status report. If a referee’s report is still outstanding at 6 months, then the Managing Editor and/or Editor contacts the referee. At this point, the referee has two options: he/she can agree to withdraw from the paper (and a new referee is sought) or can commit to producing a report within 2 months (i.e., by the end of month 8). If the referee chooses the latter option but fails to produce a report by the agreed-upon date, then the referee receives a demerit and a new referee is sought. 2. The process for dealing with revisions is the same as in (1) above, except the time epochs are reduced from 4 to 2, 5 to 3, 6 to 4, and 8 to 6 months, respectively. 3. The Managing Editor maintains an electronic list of the number of times that a referee has kept an original (revised) paper longer than 6 (4) months (i.e., the Managing Editor and/or Editor had to contact the referee) and the number of demerits received by a referee. This list will be distributed to all Area Editors and Associate Editors, but will not be made available to the community at large. 4. Sanctions are imposed on any referee who receives 3 demerits. This referee will be unable to submit any papers to Operations Research for a duration of time that is at least one year but no more than three years. The referee can reduce the sanction duration (but not to less than one year) by successfully completing a referee’s report (on a subsequent paper) for Operations Research. After a referee receives two sanctions, frequent communication between the Managing Editor and the referee will be maintained, so that the referee clearly understands the ramifications of his/her actions. 5. Although the Managing Editor and Editor will also monitor Associate Editors who have received referees’ reports but have not written their own report, at this point we plan to deal with tardy Associate Editors on a case-bycase basis. A few final comments are in order. First, this process will remain flexible enough to accommodate unusually difficult papers, personal issues (e.g., health, divorce) that the reviewers are struggling with, etc. To ensure flexibility in this process, the Area Editor and the Associate Editor have the option of allowing a referee additional time to handle an unusually difficult paper, and no demerits are incurred without the consent of the Area Editor. Second, our goal here is not to punish referees; aside from the authors, they are the Journal’s most valuable resource. Indeed, given that a referee would have to behave irresponsibly (i.e., renege on a committed 8-month lead time after being given the opportunity to withdraw in a penaltyfree manner) three times to earn a sanction, I do not foresee having to sanction anyone during my three-year appointment as Editor. Rather, our goal is to bring closure to papers that appear headed for very lengthy delays. However, we are not in a position to offer an honorarium for reviewing papers. The annual Meritorious Service Award for outstanding referees is our only concrete positive incentive. Our hope is that the presence of the monitoring process will deter referees from generating unsatisfactory delays in the review process. The resulting reductions in the review times should benefit our entire community, particularly our tenure-track faculty.

Networks have become increasingly pervasive in our lives: social networks not only have a defining impact on consumer choice but are also central in social and political decisions, ranging from political discourse in the blogosphere to the organization and coordination of protests in the Arab Spring. Economic and financial transactions also increasingly occur over large, complex, dynamically changing networks, not only contributing to the efficient allocation of resources, but also occasionally creating large, systemic, and poorly understood risks. Similarly, network effects are now seen as major elements in healthcare, smart power grids, urban transportation, and more. We invite high-quality submissions in social and economic networks, construed broadly to include any system in which human action and control play a major role. We welcome contributions based on rigorous mathematical models, as well as empirical and simulation studies, that contribute to the understanding of network formation, cascades, reliability, information and action propagation, decision making, inference, measurement, and efficient optimization algorithms over networks. We seek papers that apply tools from operations research, statistics, computer science, applied mathematics, and physics to offer novel insights, build new models, and possibly provide recommendations to policy makers. To submit your paper, go to the Operations Research ScholarOne Manuscripts site at http://mc.manuscriptcentral.com/opre and follow the instructions provided. July/August 2015: Expected issue publication date.

Networks have become increasingly pervasive in our lives: social networks not only have a defining impact on consumer choice but are also central in social and political decisions, ranging from political discourse in the blogosphere to the organization and coordination of protests in the Arab Spring. Economic and financial transactions also increasingly occur over large, complex, dynamically changing networks, not only contributing to the efficient allocation of resources, but also occasionally creating large, systemic, and poorly understood risks. Similarly, network effects are now seen as major elements in healthcare, smart power grids, urban transportation, and more. We invite high-quality submissions in social and economic networks, construed broadly to include any system in which human action and control play a major role. We welcome contributions based on rigorous mathematical models, as well as empirical and simulation studies, that contribute to the understanding of network formation, cascades, reliability, information and action propagation, decision making, inference, measurement, and efficient optimization algorithms over networks. We seek papers that apply tools from operations research, statistics, computer science, applied mathematics, and physics to offer novel insights, build new models, and possibly provide recommendations to policy makers. To submit your paper, go to the Operations Research ScholarOne Manuscripts site at http://mc.manuscriptcentral.com/opre.manuscriptcentral.com/opre and follow the instructions provided. July/August 2015: Expected issue publication date.

The aim of this note is to correct an error in the formulation of Theorem 1 by Savin and Terwiesch [Savin, S., C. Terwiesch. 2005. Optimal product launch times in a duopoly: Balancing life-cycle revenues with product cost. Oper. Res. 53(1) 26–47].

The scope and complexity of social problems that could benefit from the application of operations research (OR) models and analysis have grown immensely over the last decades. The most vexing of these problems threaten to compromise public welfare and cause social unrest. In addition, because the source of many of these problems could be traced to limited resources and competing claims on these resources, they represent a fruitful research opportunity for the field. A new special issue of Operations Research aims to showcase research that develops sustainable solutions that can improve public welfare by addressing one of the following four high impact areas: • Energy and Environment: The quest for sustainable solutions that diminish our dependence on nonrenewable energy sources and protect the environment. • Health Care: Policy proposals and recommendations to improve access to affordable quality care in both developing and developed countries. • Security and Stability: Studying policies and behaviors that affect the security of people, property, and goods, and protect the stability of governments from malevolent threats. • Critical Infrastructure: Planning, operation, and reliability of critical infrastructure such as water supplies, transportation systems, and communication networks. These areas were chosen based on input from members of the editorial board and by the recognition that these are emerging areas of research in OR and are also areas of considerable public debate worldwide. We seek papers that define important policy problems in these areas, develop novel models, ideally informed by public data sources, and make concrete policy recommendations. Submission of papers to the special issue will be preceded by a conference organized at Stanford University on June 17 and 18, 2010 and sponsored by the journal. The conference will give authors the opportunity to share their research findings with the editorial boards and other attendees, providing an early "informal" review opportunity that could help the authors in finalizing their manuscripts for submission to the journal. Authors interested in submitting a paper to the special issue should submit a three-page paper proposal describing the research problem and its main contributions. The proposals will undergo peer review, and those selected will be invited to present at the conference. The remaining proposals will receive feedback with specific recommendations regarding the potential fit with the special issue. All proposals accepted for the conference will be invited to submit a paper for the special issue. A subset of all other proposals may also be invited for submission to the journal.

The paper discusses Max-Min Facility Dispersion (MMFD) and Max-Avg Facility Dispersion (MAFD) problems. These problems are the subject of a paper by Ravi et al. (1994). The results presented in that paper include a simple heuristic for MMFD which provides a performance guarantee of 1/2, and a similar heuristic for MAFD with a performance guarantee of 1/4. It is also proved there that obtaining a performance guarantee of more than 1/2 for MMFD is NP-hard. For the two-dimensional version of MAFD, Ravi et al.'s paper presents a heuristic with an asymptotic performance guarantee of 2/p. Further additional comments in this direction are given.

O research (OR) has a long and rich shared history with economics, dating back to seminal founders of the field who spanned both disciplines (Arrow, Bellman, Dantzig, Koopmans, Modigliani, Scarf, Raiffa, von Neumann) and through a mutual interest in both problem contexts (optimal allocation of resources, inventory management, investment planning, etc.) and methodology (optimization, decision theory, game theory, simulation, etc.). While the fields diverged beginning in the 1970s, today they are growing closer as economists have recognized a need to solve increasingly complex economics models that cannot be tackled using classical methods, and OR scholars are increasingly incorporating sophisticated economic ideas into their models to reflect modern business realities. The aim of this special issue is to provide an outlet for those working at this contemporary intersection of OR and economics. We seek papers that are of broad interest to both research communities, whether it be through applications, modeling techniques that are of mutual interest, or leading-edge methodology that can benefit researchers in both fields. Methods and applications of interest include