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Coming up! Rocket Science Retailing June 27, 2009

Posted by Michael Trick in : Retailing 2009 , add a comment

The 2006 McCord Lecture paper by Marshall Fisher “Rocket Science Retailing” will be the next OR Forum Paper, available July 2.

The Evolution of Closed-Loop Supply Chain Research March 19, 2009

Posted by Michael Trick in : Closed Loop Supply Chains 2009 , comments closed

In Issue 1 of volume 57 of Operations Research (2009), Profs. Dan Guide and Luk Van Wassenhove outline how closed-loop supply chain (supply chains where the taking back of product from customers is important) research has advanced over the past 15 years or so. From the abstract:

The purpose of this paper is to introduce the reader to the field of closed-loop supply chains with a strong business perspective, i.e., we focus on profitable value recovery from returned products. It recounts the evolution of research in this growing area over the past 15 years, during which it developed from a narrow, technically focused niche area to a fully recognized subfield of supply chain management. We use five phases to paint an encompassing view of this evolutionary process for the reader to understand past achievements and potential future operations research opportunities.

To frame their discussion, Guide and Van Wassenhove identify five phases of research:

• Phase 1—The golden age of remanufacturing as a
technical problem.
• Phase 2—From remanufacturing to valuing the reverse-logistics process.
• Phase 3—Coordinating the reverse supply chain.
• Phase 4—Closing the loop.
• Phase 5—Prices and markets.

You can read the full paper here: The Evolution of Closed-Loop Supply Chain Research.

The Editors of Operations Research have invited two leading scholars to provide their comments on this article. The first commentary is by Robert D. Klassen, Professor of Operations Management and J.J. Wettlaufer Faculty Fellow at the Ivey School of Business, University of Western Ontario, Canada. Dr. Klassen’s primary point regards the definition of “business value”

At the outset, and later emphasized again, Guide and Van Wassenhove (2009) narrowed their tutorial to a business perspective on value-added recovery activities. While it is always helpful to clearly delimit what is being examined, it also is important to critically assess if the limits exclude strategically or methodologically important aspects. And defi ning business value has become a rather contentious issue subject to increasingly complex debate, particularly with growing interest in sustainable development.

You can read Dr. Klassen’s full commentary: Klassen Commentary.

The second commentary comes from Dr. Moritz Fleischmann, Associate Professor of Supply Chain Management, Rotterdam School of Management. In his commentary, Dr. Fleischmann takes issue with some of the divides identified by Guide and Van Wassenhove:

Somewhat less convincing, in my opinion, are some of the presumed `dualities’ in the research development in the eld of CLSCs. This includes, for example, the `US market-driven approach’ and the `European waste-stream approach’ mentioned in Section 5. While there are certainly important di fferences between countries regarding their legislative context, this does not mean that pro fit driven CLSCs and corresponding research are a U.S. phenomenon exclusively (as documented e.g. in the book of Flapper et al., 2005, cited in this paper). Likewise, I do not observe the suggested stark contrast between `OR-based’ research and `business economics’ research (again Section 5) since many of the papers cited in the second stream also make use of OR techniques.

Dr. Fleischmann’s full commentary is here: Fleischmann commentary

Drs. Guide and Van Wassenhove have provided a response to the commentaries: Guide and Van Wassenhove Reponse.

Now is your chance: what do you think the role of closed-loop supply chains has been? What is the state of research, and where is this field going? Feel free to add your comments or respond to the paper and commentaries.

Personal Decisions are the Leading Cause of Death January 6, 2009

Posted by Michael Trick in : Health Decision Making 2008 , comments closed

In the November-December 2008 issue of Operations Research, Dr. Ralph L. Keeney of Duke University, in the paper “Personal Decisions are the Leading Cause of Death”, argues that personal decisions cause a large fraction of the deaths in the United States, with the vast majority of those decisions resulting in the death of the decision maker. Some of the key decisions people make involve diet, alcohol and drug use, exercise and driving habits. From the abstract:

This paper analyzes the relationships between personal decisions and premature deaths in the United States. The analysis indicates that over one million of the 2.4 million deaths in 2000 can be attributed to personal decisions and could have been avoided if readily available alternative choices were made. Separate analyses indicate 46% of deaths due to heart disease and 66% of cancer deaths are attributable to personal decisions, about 55% of all deaths for ages 15–64 are attributable to personal decisions, and over 94% of the deaths attributable to personal decisions result in the death of the individual making the decisions. Relative to the current 45%, retrospective appraisal suggests that roughly 5% of deaths in 1900 and 20%–25% of deaths in 1950 could be attributed to personal decisions. These results suggest that more effort directed toward improving personal choices regarding life risks may be an effective and economical way to save lives.

You can read the full paper here: Personal Decisions are the Leading Cause of Death

The editors of Operations Research, led by Area Editor Stefanos Zenios, asked a number of leading researchers to provide commentary on this paper.
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Catching the “Network Science” Bug November 19, 2008

Posted by Michael Trick in : Networks 2008 , comments closed

In the September-October, 2008, issue of Operations Research, David Alderson of the Naval Postgraduate School offers insights and opportunities for operations researchers in the area of network science. From the abstract:

Recent efforts to develop a universal view of complex networks have created both excitement and confusion about the way in which knowledge of network structure can be used to understand, control, or design system behavior. This paper offers perspective on the emerging field of “network science” in three ways. First, it
briefly summarizes the origins, methodological approaches, and most celebrated contributions within this
increasingly popular field. Second, it contrasts the predominant perspective in the network science literature
(that abstracts away domain-specific function and instead focuses on graph theoretic measures of system
structure and dynamics) with that of engineers and practitioners of decision science (who emphasize the
importance of network performance, constraints, and tradeoffs). Third, it proposes optimization-based reverse
engineering to address some important open questions within network science from an operations research
perspective. We advocate for increased, yet cautious, participation in this field by operations researchers.

You can find the full article here.

The editors of Operations Research have invited four senior researchers to provide commentaries on this work.

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The OR/MS Ecosystem: Strengths, Weaknesses, Opportunities and Threats April 23, 2008

Posted by Michael Trick in : Ecosystem 2008 , comments closed

In the March/April issue of Operations Research, ManMohan Sodhi and Christopher Tang look at operations research/management science and discuss how research, teaching, and practice interact in our field. From the abstract:

We believe that research, teaching, and practice are becoming increasingly disengaged from one another in the OR/MS ecosystem. This ecosystem comprises researchers, educators, and practitioners in its core along with end users, universities, and funding agencies. Continuing disengagement will result in OR/MS occupying only niche areas and disappearing as a
distinct field even though its tools would live on. To understand the reasons for this disengagement better and to engender discussion among academics and practitioners on how to counter it, we present the ecosystem’s strengths, weaknesses, opportunities, and threats. Incorporated in this paper are insights from a cluster of sessions at the 2006 INFORMS meeting in Pittsburgh (“Where Do We Want to Go in OR/MS?”) and from the literature.

This article, dedicated to Art Geoffrion who, as the authors state, is a “role model of a great research, educator and practitioner” in OR/MS, is a call for increased interaction between all those interested in our field.

For an ecosystem to thrive, efforts have to be made in increasing healthy interaction on many fronts. Specifically,…, we believe that (1) academic journals editors could serve as catalysts for making the ecosystem healthier by publishing more multidisciplinary papers that reflect the core strengths and uniqueness of OR/MS, (2) researchers could initiate efforts for strengthening the links with end users and practitioners, and (3) educators (especially in business schools) could enlist support from practitioners and end users to motivate more students to become OR/MS practitioners or end users.

You can find the full paper here.

The editors of Operations Research have invited two prominent educators and researchers to comment on this paper.
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Simple Models of Influenza Progression within a Heterogeneous Population June 15, 2007

Posted by Michael Trick in : Influenza 2007 , comments closed

In the May-June, 2007, issue of Operations Research, Professor Richard C. Larson looks at the role that operations research can place in one of the most pressing issues of our time: handling a possible influenza pandemic. In his abstract, he outlines his goals:

The focus of this ‘OR framing paper’ is to introduce the OR community to the need for new mathematical modeling of an influenza pandemic and its control. By reviewing relevant history and literature, one key concern that emerges relates to how a population’s heterogeneity may affect disease progression. Another is to explore within a modeling framework ‘social distancing’ as a disease progression control method, where social distancing refers to steps aimed at reducing the frequency and intensity of daily human to human contacts. To depict social contact behavior of a heterogeneous population susceptible to infection, a non-homogeneous probabilistic mixing model is developed. Partitioning the population of susceptibles into subgroups, based on frequency of daily human contacts and infection propensities, a stylistic difference equation model is then developed depicting the day-to-day evolution of the disease. This simple model is then used to develop a preliminary set of results. Two key findings are (1) early exponential growth of the disease may be dominated by susceptibles with high human contact frequencies and may not be indicative of the general population’s susceptibility to the disease; and (2) social distancing may be an effective non-medical way to limit and perhaps even eradicate the disease. Much more decision-focused research needs to be done before any of these preliminary findings may be used in practice.

In the paper, Prof. Larson provides a number of simple, yet plausible, difference equations and uses them to model influenza spread in and environment with a population that is heterogeneous in the amount of social interaction made. In his conclusions, Prof. Larson describes his view of the rationale and importance of this research:

No one knows how or when the next pandemic influenza will emerge and what its intrinsic properties will be. If history can be a guide, the next influenza will have ‘emergent properties,’ meaning that it will mutate during the course of the epidemic and its intrinsic properties will evolve accordingly. Any mathematical model of the disease and its control is bound to be incorrect. But we are not seeking multi-decimal numerical accuracy but rather insights on how to limit the spread of the disease. We firmly believe that fresh eyes from the OR community can play a significant role in this quest.

You can read the full paper here along with its online companion.

The editors of this journal have invited three individuals and groups to comment on Prof. Larson’s paper.
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Thirteen Reasons Why the Vickrey-Clarke-Groves Process is Not Practical April 17, 2007

Posted by Michael Trick in : Auctions 2007 , comments closed

In the March - April 2007 issue of Operations Research, Michael Rothkopf of Rutgers University argues that the well-known Vickrey-Clarke-Groves process for auctions is not practical. The abstract reads:

In theory, the mathematically elegant Vickrey-Clarke-Groves process offers perfect efficiency with dominant truth-revealing strategies. However, it has many serious practical problems. This paper describes these problems and argues that research that aims to maintain the dominant truth-revealing strategies while compromising on the other practical issues is of limited practical value.

Rothkopf goes on to discuss thirteen reasons for this limited value. These are

  • the fact that the dominant strategy equilibrium is a weak equilibrium and there may exist alternative weak equilibria,
  • the nonexistence of dominant strategy equilibria in models that include reasonable bid preparation costs,
  • the exponential growth of effort related to bid preparation and bid communication,
  • the NP completeness of the winner determination problem,
  • problems related to capital limited bidders,
  • problems associated with the disclosure of valuable confidential information,
  • problems associated with various kinds of cheating including
    • false bids by the bid taker,
    • conspiracies by competing bidders,
    • conspiracies in two-sided markets between bidders offering to sell and those offering to buy,
    • and the use of false name bids by single bidders,
  • the fact that strategies in sequences of strategy-proof auctions may not be strategy-proof,
  • and the fact that the process can be revenue deficient.

You can find the entire article here.

The editors of Operations Research have invited three researchers to provide commentary on this paper:
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Introduction to the OR Forum March 11, 2007

Posted by Michael Trick in : Administration/ Announcements , comments closed

The OR Forum is an area of the journal Operations Research, published by the Institute for Operations Research and the Management Sciences (INFORMS). The purpose of the Forum area is spelled out in its mission statement:

The OR Forum area invites work that challenges the reader to consider and evaluate the status of past, present, or future prospects and challenges within the field of operations research. Possible submissions include critical reviews of research in a specialized field, closely reasoned commentary on the practice within an area, analysis of prospects for operations research broadly, or any other area where a substantive, significant work will clarify and illuminate research and practice. Published work will often be accompanied by supplemental pieces that enhance or dispute the theses developed.

An online forum will provide opportunity to continue the discussion after publication. Papers that address prospects in areas not traditionally covered by Operations Research are strongly encouraged, as are provocative papers that take a strong stand on policy and practice issues. The arguments made in the paper should not be casual or speculative, but should be based on a firm foundation consistent with publication in a professional journal. Survey papers are appropriate providing such papers go beyond a listing of who wrote what to include a critical appraisal of the research and the prospects for the future. The work should be accessible and of interest to a significant portion of the readership of Operations Research. Authors are encouraged to contact he Area Editor early in the process of developing their work to determine suitability for consideration in this area.

This site is an adjunct to the published papers in the journal. At this site, we invite commentary and discussion of each of the OR Forum’s papers. There is no set time-limit to this discussion, and interested readers are invited to check back periodically for updates.

All comments and posts are moderated for content by the Area Editor, Michael Trick (trick@cmu.edu) .

Welcome to the OR Forum!