Michael Trick's Operations Research Blog (ORB)

I'm Moved!

2006-05-15T15:42:00.000-04:00

I have moved this blog. If your browser does not automatically redirect, please click here.

Change of Software?

2006-05-14T14:40:00.000-04:00

Now that I have gone over 50 posts, it looks like I will keep this blog going (thanks to the loyal reader out there!). Right now, the blog is hosted by blogger. I have now installed wordpress on my own machine, and have transferred things over. Having my own wordpress installation allows me more flexibility in add-ons for the blog. Can anyone make the case for keeping it on blogger? You can compare at the new system.

Optimize magazine and Operational Excellence

2006-05-05T19:48:00.000-04:00

Optimize is a 70,000 circulation magazine aimed at CIOs and CTOs. The topic of the May, 2006 issue is "Operational Excellence", and it contains a host of articles about operations research, one done by yours truly. My article, entitled "CIO as Business Predictor" tries to talk about the role uncertainty plays in decision making and how OR approaches can help address these issues. The sidebars in the article describe the finalists in this year's Edelman Competition.

A second article, entitled "Bringing Unity to Cardinal Health", described how IT and operational excellence go hand-in-hand. There is a sidebar of an interview with Irv Lustig from ILOG on the how IT and OR interact.

The Editor's Note to the issue also talks about OR quite a bit, and says some very nice things about me! I think I will get it framed and send to my mother.

Between this and the coverage by Stephen Baker from Business Week, OR is getting noticed quite a bit these days in the more mainstream press.

Stephen Baker on Operations Research

2006-05-05T19:36:00.000-04:00

Stephen Baker, the author of the Business Week cover story on how Math Will Rock Your World, is rapidly becoming a highly visible writer about Operations Research. His May 4 blog entry, entitled "Why journalists don't cover how things work" had some comments on his experience at the INFORMS Practice Conference:

At the O.R. conference (the association is called INFORMS), there were far too many interesting presentations for one person to cover them all. The people behind operations at Intel, IBM, the Army, Ford and plenty of others provided inside looks. Beat reporters of those companies could have feasted on these lectures. But they weren't there.

Why? The press covers news, stocks, companies and personalities. But try pitching a cover story on operations. People think it's ... boring. Trouble is, if we want to know where things are going, we have to understand how they work. And when the process is transformative, as it often is in OR, there's nothing boring about it. The winner of the annual Informs Franz Edelman award, by the way, was the Warner Robins Air Logistics Center. They overhauled the maintenance of jumbo C-5 transport aircraft, reducing repair time by 33%. This means that these monsters, which cost taxpayers $2.3 billion each, spend more time in the air and less time in the shop.

If Stephen keeps this up, we may see lots more press coverage.

Great Newsletter

2006-04-28T08:05:00.000-04:00

The publishers of OR/MS Today (the membership magazine of INFORMS) have started an online and email newsletter. The first issue contains a large number of short, interesting tidbits from the world of (practical) OR. Feel free to subscribe so it shows up in your mailbox as soon as it is published.

Edelman Competition

2006-04-28T07:55:00.000-04:00

This year's Edelman Competition will take place in a few days at the INFORMS Practice Conference. The Edelman Competition presents projects in practical operations research that have a significant impact on an organization. This year's finalists include work from Travelocity, the TSA, Warner Robbins Air Logistics, Center and more. I really like the Edelman: the finalists put papers into Interfaces, and those papers are a tremendous resource for my MBA classes.

Of course, every competition could be improved. I was mulling on the thought of turning this competition into a reality show. Lock a bunch of ORers in a plant for six weeks with cameras everywhere, and watch them try to out-optimize each other to be the last one standing. Probably wouldn't compete with American Idol, but I certainly would watch it!

IBM's Center for Business Optimization

2006-04-20T08:25:00.000-04:00

I am in New York to give a talk to IBM's Center for Business Optimization. Bill Pulleyblank is heading this activity. Bill has had a really interesting career: he started in academia, and did really fundamental work in combinatorial optimization. He then moved to IBM, starting at Watson Research and moving on to doing things like heading the Blue Gene Project, which created the world's fastest supercomputer. CBO is a startup with IBM that tries to merge the assets of IBM (software packages, etc.) with the consulting skills of IBM Business Consultants (formerly PriceWaterhouseCooper's consulting arm).

It is exciting to see a company like IBM take optimization seriously. The projects I have chatted with people about look like "real" optimization and business analytics: data mining and modeling approaches to fraud dectection (both tax fraud and Medicare fraud), supply chain optimization, marketing design, and so on. They have a number of case studies that outline their various projects.

Operations Research Job Prospects

2006-04-12T14:01:00.000-04:00

Money Magazine and salary.com have a ranking of 166 job titles, based on salary and job prospects. I was happy to see "College Professor" as the second best job (good salary, good growth, lots of freedom). Having Operations Research Analyst mired in roughly 120th place (out of 166) was less fun to see. The salary for the field is good, but job growth was relatively low. Still, OR Analyst beat out mathematician, economist, physicist, librarian and many other seemingly appealing fields.

Descriptive versus Prescriptive

2006-04-09T17:50:00.000-04:00

Working in a business school (the Tepper School at Carnegie Mellon), many of my colleagues are economists (or "financial economists" as many of my finance colleagues are titled). One of the big hurdles we have in communicating is a differing view of the purpose of models. For many economists, models are used to describe behavior. For instance, a model of certain types of incentives may lead to particular outcome behavior. If we see the outcome behavior, this suggests the model is a good one. If an economist does not see the outcome behavior, then there is a puzzle at best, and a bad model at worst.

For an ORer (a word I just made up, because OR person sound stilted), models are almost always prescriptive: they tell you what to do. For that same model, an ORer will, if happy with the model, not worry about whether the outcome behavior is happening. If not, then people are doing things wrong, and should smarten up and follow the OR prescription.

Articles like the one today in the New York Times (subscription required) make me feel happier about the OR approach. People, even reasonably sophisticated people, just don't seem to make good decisions. The example is drawn from finance, but examples abound:

MANY index funds track the Standard & Poor's 500, but they differ from one another in one major respect: their fees. You'd think that it would be obvious to investors to pick the fund that charges the least. But you'd be wrong.

In fact, this truth was anything but obvious to a group of elite students. In an elaborate simulation created by several researchers, many students at Harvard and the Wharton School of the University of Pennsylvania failed to select the lowest-cost index fund for their portfolios, even when they were all but spoon-fed the right answer.

...

In the first simulation, the professors asked 30 undergraduates at Harvard and Wharton, as well as 83 M.B.A. students at Wharton, to allocate a hypothetical $10,000 among four S.& P. 500 index funds that would be held for one year. All four funds invested in the same 500 companies, and matched the index's allocation for each stock, so the only significant difference in the funds' returns would come from their fees — their front-end loads, or sales charges, and their management expenses. And because of the way the professors designed the experiment, these four funds had relatively high fees, ranging from 3.09 percent to 5.89 percent.

Each student received copies of the four index funds' prospectuses, which varied from 26 to 116 pages long. The prospectuses provided detailed descriptions of the funds' loads and expenses, along with a great deal of other information. To encourage the students to take the exercise seriously, each was paid a small amount — $5 for undergraduates, $20 for M.B.A. students — and was told that one student at each school, picked at random, would receive any profit that the $10,000 portfolio produced over the 12 months.

The rational response, the professors argue, would have been to allocate all the money to the fund with the lowest fees. Yet fewer than 20 percent of either group of students did so. As a result, the hypothetical portfolios built by most of the students paid much higher fees than were necessary: 1.22 percentage points more, on average, among the undergraduates and 1.12 points higher among the M.B.A. students.

The work was done by James J. Choi, an assistant professor of finance at the Yale School of Management; David Laibson, an economics professor at Harvard; and Brigitte C. Madrian, a professor of business and public policy at the Wharton School. A copy is at http://www.som.yale.edu/faculty/jjc83/fees.pdf.

Makes me happy to be prescriptive!

New MLB Scheduler

2006-04-05T16:43:00.000-04:00

Some of you may know that I have been working with Major League Baseball for a number of years on scheduling issues. Finally, in 2005 they played a schedule created by a small firm that I am a partner in. Unfortunately, we got beaten out for the 2006 schedule, as MLB.com reports. We'll get them in 2007!

Want to learn more about Constraint Programming?

2006-04-04T15:17:00.000-04:00

Thom Frühwirth and Slim Abdennadher have a book called "Essentials of Constraint Programming". Best of all, Thom has more than 400 powerpoint slides on his website to supplement the book.

David Simchi-Levi Presentation

2006-03-24T10:35:00.000-05:00

David Simchi-Levi is here at CMU today speaking on inventory systems where the decision maker is not risk neutral. David is a professor at MIT and Editor-in-Chief of Operations Research. He also runs his own company, LogicTools. I think he has given up sleep.

It is surprising that there is so little research on risk-averse decision makers in the operations management context. This clearly is a useful integration of economic theory and operations research and also involves the interface between finance and operations in a firm. In David's work, even marketing comes into play since prices can be set in the model in order to influence demand.

Work like this often spends time in pages of greek letters with subscripts, and this paper is no different (though David is an excellent lecturer, so it was not as mind-numbing as some lectures like this).

With fixed costs for ordering, even models with risk neutral decision makers are hard to solve. Normally, the optimal decisions are set with an (s,S,p) policy: if inventory is under s, order up to S, and set price p. But suppose the inventory level is a bit above s. Should price be set high in order to decrease demand or should the order go up to S, and price be set low. This example shows that the price has a discontinuity, making it hard to get characteristics of the solution.

With risk aversion, things get more complicated. For the case where there is no fixed ordering cost, the optimal policy is a base stock policy, but the base stock level depends on the wealth level of the decision maker. With fixed costs, for exponential utility, the optimal inventory policy is independent of wealth, making things a bit easier (though it is still hard to figure out the exact policy).

One interesting aspect of this that came up in Q&A is the need to combine pricing and inventory decisions. Most companies are not aligned this way: marketing sets price, while operations sets inventory. Even in these complicated models, though, the results generally look like "Operations, do (s,S); Marketing, set price p". This suggests very tight integration is not needed: coordination is enough.

When you add financial hedging aspects, there is still this decoupling aspect: the financial decisions do not affect the operational decisions.

It would take someone more skilled than I to explain these results to a general audience, but I find it interesting that models that contain all of marketing (price setting), operations (inventory setting) and finance (hedging) are amenable to analytical solution. This seems a very rich research area.

A Stonewall Connection to Operational Research

2006-03-23T09:35:00.000-05:00

My parents grew up on farms outside a then-small (now medium) sized town in Manitoba named Stonewall. For a period in the early 1900s, a boy named Charles Goodeve lived in Stonewall. He lived there for about 10 years, before his family moved to Winnipeg. There is an article in the Stonewall Argus (the Gordon Trick mentioned is my father) about his life, including his work during World War II in the British Navy. Among other things, he figured out how to protect ships from underwater mines through a demagnetization process.

The operational research connection? In 1948, Sir Charles Goodeve founded the OR Club, which would later become the Operational Research Society.

Tournament Time!

2006-03-15T21:57:00.000-05:00

The NCAA Tournament is irresistable to OR types. Predicting the tournament has proven a rich area of application. Jay Coleman of the University of North Florida has a scorecard approach that gives probabilities of wins for every game in the first round. For three of the 32 games, his approach favors the lower seeded team (including number 10 Alabama over number 7 Marquette. As far as number 1 seeds go, his method gives a 99%+ chance to Villanova and Duke in their first game (a number 16 has never beat a number 1) but just 97% for UConn and 95% for Memphis.

Joel Sokol of Georgia Tech has done a lot of work in this area. He has some interesting comments on the 2006 brackets.

INFORMS has some other pointers in this area.

Anyone else like to talk about their OR approaches to this?

Operations Research and CIOs

2006-03-15T14:41:00.000-05:00

United Airlines now has a CIO who is also responsible for operations research and other activities. This seems a natural, if somewhat unusual move (OR is often under manufacturing, operations or some other structure). OR is all about using information, and as firms realize the value of information (and CIOs) is in their ability to extract knowledge from information, more OR may be in the hands of the CIO.

Applied Mathematical Programming

2006-03-01T04:46:00.000-05:00

One of my all time favorite textbooks is Applied Mathematical Programming by Bradley, Hax, and Magnanti. This text is now available on the web!

Passing of Joan Wingo

2006-02-19T17:04:00.000-05:00

The field of operations research is full of unsung heros: people who make the field better by doing their jobs with enthusiasm, creativity, and skill. If you have published in Operations Research over the last six years, or if you have read and admired papers in that journal, you will have seen the work of Joan Wingo, Managing Editor of Operations Research. Joan worked with Editor-in-Chief Larry Wein to make Operations Research run, and run well. I worked with Joan over the last few months on transition issues with the new editorial board.

Joan, sadly and untimely, passed away February 13. Her obituary notice contains some thoughts of her friends, coworkers and loved ones. We, as a field, owe her a great deal.

New Editors at Operations Research

2006-02-19T17:00:00.000-05:00

The INFORMS journal Operations Research has a new editorial board, led by Editor-in-Chief David Simchi-Levi. David asked me to take on the area of OR Forum. I was hesitant to take on an editorial duty (handling papers has turned out to be an Achilles heel of mine), but the opportunity to handle papers that inspire discussion and controversy was too much to turn down. Here is the area 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.

Any thoughts for suitable articles?

PhD salaries

2006-02-09T09:03:00.000-05:00

Forbes magazine has an article about the lack of mathematically trained US workers. Most of the article is about outsourcing, but the issu of starting salaries came up:

A person fresh from graduate school with a Ph.D. in operations research can make $90,000 at SAS Institute--far less than the $150,000-plus salaries top MBAs can command. "Yes, fine, we need to pay more," Steve Odland, CEO of Office Depot admitted.

Well, kinda... First, a fresh MBA rarely makes $150,000: the average Tepper MBA graduate is closer to $90,000. Second, the lifestyle of those who make the high amounts in terms of stress, travel, and so on is pretty rotten, at least by my standards. Finally, there are lots of fresh Ph.D.s in OR making more than $90,000, often teaching those same MBAs!

Not to say that Ph.D.s should make lots of money (I am one of them myself!), but that doesn't seem the most dire aspect: it is really the lack of supply of interesting jobs that allow the true use of an OR Ph.D.

Doing research already done?

2006-02-04T22:56:00.000-05:00

The New York Times has a nice article about how research is often rediscovered. The lead begins about operations research:

In 1996, Rakesh Vohra, a professor at Northwestern University, and his colleague Dean Foster published "A Randomized Rule for Selecting Forecasts," a paper in the journal Operations Research. It illustrated how a random investor could outperform a group of professional stock pickers simply by following a "buy and hold" investment strategy.
Skip to next paragraph
Alain Pilon

It was important research, the authors believed, until they learned that the same discovery had been made at least 16 times since the 1950's. And no one, Dr. Vohra said, ever realized they were not doing original work.

As a referee, there are certain things in sports scheduling that I get quite often (generally some variation of de Werra's work on minimum break scheduling) and I recently went a long way on a paper before de Werra pointed out to me that the results were included in a somewhat more obscure publication of his. I wonder if online search will make it easier to find these duplicate results before it makes the literature?

Happenings in Cork

2006-01-22T08:14:00.000-05:00

I have just returned from a site visit to the Cork Constraint Computation Centre (4C: it's a pun, don't you know) in Cork Ireland, where I am on the advisory board. Ireland is a country that seems to have its government investments set up well. A few years ago, they a identified Gene Freuder as someone they would like to attract and made him a very nice offer. Gene is one of the (or perhaps the main) founders in the area of constraint programming, and he has put together an extremely impressive lab. Lots of activity, both in fundamental research and in industrial outreach. The lab isn't perfect (more OR!), but it is very, very good. If you are learning more about constraint programming, this lab's site is a good place to start.

Additional Online info at Business Week

2006-01-15T20:27:00.000-05:00

There is an additional article online (only) associated with the "Math will Rock Your World" article in Business Week. Entitled Search Advertising by the Numbers, the article concentrates on the problem of bidding on keywords. Here is a quote:

Khan, an accountant by training, looks at the process like a linear programming problem. That may sound exotic to mathophobes, but the concept is simple. He sets a goal that he aims to maximize. In Khan's case, that's revenue. Then he factors in the constraints, such as cost per keyword.

This can get complicated. If he bids for the word "loan," for example, he competes with much of the lending industry. That drives up the price. What's more, it's a big, broad word, which means the results are much more complex than a far cheaper targeted keyword phrase such as "Tuscaloosa mortgage."

"If we can get one dollar out of an auto loan, we can get $20 if we do a mortgage loan," Khan says. "A keyword like 'loan' can deliver either of the two products. So should we buy the keyword based on potential of auto loan or mortgage loan?" He has his team do the math

As always, the article doesn't go into any real detail of models or algorithms, but it does make our field much more visible.

Business Week

2006-01-13T06:17:00.000-05:00

Just as I was bemoaning the lack of press coverage, Business Week comes up with a cover story entitled "Math Will Rock Your World". The field of operations research is even mentioned by name, which is a tremendous step for the area!

Does your library have all the INFORMS Journals?

2005-12-30T12:40:00.000-05:00

INFORMS is running a grass-roots effort to get more libraries to carry INFORMS journals. They have a neat setup that you can check if your (university) library carries every journal. You can even email your librarian to encourage subscriptions.

Most libraries are cutting back on journals, partially due to some extremely high prices on journals. INFORMS journals, being published by INFORMS, are quite reasonably priced, but of very high quality. Every library should have them!

Sad News from India

2005-12-29T04:46:00.000-05:00

From the Indian Express:

Terror struck an international conference at the Indian Institute of Science (IISc) campus on Wednesday night killing a retired Mathematics professor from the Indian Institute of Technology, Delhi, M.C. Puri, and seriously injuring four others including one of the inventors of the Simputer, Prof Vijay Chandru from IISc.

The attack was, according to eyewitness accounts, carried out by a lone gunman who wielded an AK-47 and threw hand grenades. The attacker was driven away in a white Ambassador car immediately after the attack, eyewitnesses said.

All major cities in south India have been put on high alert after the incident.

The other injured persons have been identified as Dr Pankaj Gupta from Delhi, P Patel, a lab assistant at the Cadila Lab in the IISc campus, and a woman identified only as Sonia, an assistant professor at IIM, Lucknow.

‘‘All the injured have been ruled to be out of danger,’’ Additional Commissioner of Police H C Kishore Chandra said.

Delegates at the International Conference on Operations Research Applications in Infrastructure Development and the 38th Annual convention of Operation Research Society of India (ORSI) were proceeding from IISc’s National Science Seminar Complex to the Satish Dhawan auditorium for an AGM of the ORSI at around 7:30 p.m. when the attack took place.

Full Story

Vijay Chandru is a co-author of mine, and my thoughts are with him, the others injured and the family of Prof. Puri.

Happy (belated) Christmas

2005-12-28T15:45:00.000-05:00

I was off in Germany for the last week, without an internet connection. Hope you all had an optimal Christmas!

Christmas and OR

2005-12-13T11:45:00.000-05:00

It is Christmas time, so lots of people are waiting in line, and talking about it. Naturally, this leads to some OR related articles. Ivars Peterson in his Math Trek column at Science News talks about parking strategies: do you park and walk, or cycle through hoping for a better spot (seems the better is generally the better strategy). And the Birminham News is the latest to talk about Dick Larson's work on queue behavior.

OR and Suicide Bombs

2005-12-12T18:14:00.000-05:00

This past weekend, the NY Times Magazine in its annual Ideas issue reports on Ed Kaplan's work with Moshe Kress on damage done by suicide bombers. Here is an excerpt:

Even if you manage to detect a suicide bomber, what do you do next? This question was taken up by Edward H. Kaplan, a professor of public health at Yale, in a paper he published in July, written with Moshe Kress of the Naval Postgraduate School in Monterey, Calif. Kaplan and Kress investigated the physics of a belt-bomb blast and reached some unexpected conclusions. It turns out that very few people are killed by the concussive force of a suicide explosion; the deadly weapon is in fact the shrapnel - the ball bearings, nails or pieces of metal that the attacker attaches to the outside of his bomb. The explosions, though, are usually not powerful enough to send these projectiles all the way through a human body, which means that if your view of a suicide bomber is entirely obscured by other people at the moment of detonation, you are much more likely to escape serious injury. Because of the geometry of crowds, Kaplan found, a belt bomb set off in a heavily populated room will actually yield fewer casualties than one set off in a more sparsely populated area; the unlucky few nearest to the bomb will absorb all of its force.

The authors used these calculations to question some assumptions about what authorities should do if they detect a bomber. The International Association of Chiefs of Police issued guidelines this year suggesting that police officers who find a bomber in a crowd should fire shots into the air to cause people near the bomber to scatter or hit the deck. But Kaplan's calculations demonstrate that in many cases, this would make things worse - as a packed crowd ran away from a bomber or dropped to the ground, the circle of potential victims around him would get wider and thus more populous, and more lives could be lost.

Amazing what a little OR will teach you!

Book blurb

2005-12-08T09:07:00.000-05:00

Springer has just published a new book containing introductory tutorials on a range of optimization subjects: Search Methodologies: Introductory Tutorials in Optimization and Decision Support Techniques. Of course, I have a vested interest: Bob Bosch and I wrote the Integer Programming chapter, which I think came out quite nice!

Wikipedia and Operations Research

2005-12-06T06:47:00.000-05:00

Wikipedia is in the news, due to some inaccurate/obnoxious/insulting entries regarding a journalist and alleged involvement in the Kennedy assassinations.

Wikipedia is an interesting effort to harness the knowledge and energy of hundreds of thousands of people to form a new type of encyclopedia. The key aspect is the ability to freely enter information (or misinformation) and edit what is there.

The entry for operations research is pretty good, covering both the general (what is OR) and the specific (some military and other examples). The pointers are well selected. The "history" gives all the past edits, and it is striking how many edits went into this entry alone. That is one advantage of multiple people working on it: 100 edits don't seem bad if 50 people are doing them.

But what is to stop someone from putting "Operations Research is an upsidedown cake with cherries" into the entry? As this Wired article describes, with enough interested volunteers, such vandalism can get corrected within minutes. Of course, that assumes the entry is in an area with knowledgeable and active volunteers. I wonder how much misinformation is stored in the backwaters of wiki.

Despite the doubts, I think a wiki based Encyclopedia of OR would be a tremendous asset for the field. While some expert-based encyclopedias are fine (Gass and Harris have a good one, at an astounding $620 new), a community based wiki would be more up-to-date and be able to cover far more.

More on Scientific Publishing

2005-12-04T18:01:00.000-05:00

Wired magazine pointed me to www.badscience.net, which is fascinating! There was a posting relevant to issues of publishing science which seems very relevant to OR:

Science is done by scientists, who write it up. Then a press release is written by a non-scientist, who runs it by their non-scientist boss, who then sends it to journalists without a science education who try to convey difficult new ideas to an audience of either lay people, or more likely - since they’ll be the ones interested in reading the stuff - people who know their way around a t-test a lot better than any of these intermediaries. Finally, it’s edited by a whole team of people who don’t understand it.

Lots of good stuff there.

OR in the media and Virginia Postrel

2005-11-26T14:39:00.000-05:00

Operations Research has a hard time getting into the press. Partially it is our fault: OR people as a whole are pretty modest and are great at seeing two sides to every issue (after all, it is this dynamic that makes for the best models: start small, and add to address issues with the resulting solutions). I am certainly guilty of this: I turned down more requests to talk about my work with Major League Baseball than I can count, due primarily to worries about client relations and being accurately portrayed.

Partially it is the fault of much of the media, who are unwilling to assume a very high "lowest common denominator" in their readership. OR continues to be a weird black box, and our core values of analytical thinking, using data, and working with models are rarely portrayed.

One person who does get it is Virginia Postrel, who wrote a very fine article for the Boston Globe last year (and I don't say that just because I am quoted!). Here is what she had to say about publishing about operations research (in the context of the rise in productivity, which OR certainly contributes to):

In today's Boston Globe Ideas section, I look at one piece of that very big story [the rapid rise in productivity]: the spreading use of operations research techniques once confined to theory. (What's operations research? The story explains that too, or tries to without using any math, graphs, or jargon about optimizing subject to constraints or finding interior solutions. For more on the field, see the INFORMS site.)
Of course, very few general-interest publications would let a writer spend nearly 2,000 words writing about operations research--or, for that matter, rising productivity.

I stumbled across her website and blog, and she has a number of interesting posts on productivity (generally her 2004 posts, like the one I quoted that mentions her OR article). Her recent work is on glamor and aesethics, which doesn't appeal to me as much but might to others. Lots of interesting things to read throughout her website.

Initial Plans for INFORMS 2006

2005-11-26T14:22:00.000-05:00

Now that INFORMS 2005 New Orleans/San Francisco is over, it is the Pittsburgh crowd's turn to put together INFORMS 2006. We are well on the way planning, with a list of tutorials and invited sessions that I think will be very good.

The theme of the conference in OR Renaissance, and we hope to highlight some of the exciting new directions and applications for OR/MS. We'll have some new things in store for 2006 including

1) A new Tuesday reception, planned for PNC Park, the site of the 2006 MLB All-Star game.

2) "Renaissance Sessions", highlighting the best of where OR will be in 5 years.

3) Plans for a revamped awards ceremony.

The Monday General Reception will be at the wonderful Carnegie Museums: the Museum of Art and the Museum of Natural History (they are connected).

The conference will be November 5-8, 2006. If you have some thoughts on how INFORMS conferences could be made better, I'd love to hear them. Comment here or mail to me.

Rothkopf's Rankings of University Contributions to the Practice Literature

2005-11-23T06:50:00.000-05:00

Mike Rothkopf has just published his sixth ranking of universities in publishing in the practice of operations research in the journal Interfaces (subscription required to access full paper). The definition of "practice" is naturally a complicated thing: most OR people (myself included) claim relevance to practice on pretty slim connections. For this ranking, "practice" means publishing either in Interfaces or in the OR Practice area of Operations Research. My own school, Carnegie Mellon, came out on top with 10 such publications (1998-2004). The next part of the rankings are
2. University of Pennsylvania
3 (tie). Georgia Institute of Technology and Naval Postgraduate School
5. Cornell, Stanford, University of Texas at Austin, and University of Virginia

Non-US schools are ranked separately. Top is Erasmus University with 7 papers (same as Cornell, etc. on the US list).

John Muth

2005-11-21T19:19:00.000-05:00

John Muth passed away in October. He was an early faculty member at the school I am at (the Tepper School at Carnegie Mellon) and a key researcher in the economic area of rational expections. What is the OR content? Check out his obituary and note the work in operations management and forecasting along with his work in economics and finance. Not many people about these days that would try to span those areas!

INFORMS Awards

2005-11-14T17:11:00.000-05:00

I just got back from the INFORMS Award ceremonies. Some of the highlights:

1) John von Neumann Theory Prize went to Robert Aumann, who also won the Nobel Prize in Economics this year. The committee picked Aumann before the Nobel Prize was announced. Pretty good year for Robert!

2) The Lanchester Prize (best publication in English) went to Garrett van Ryzin and Kalyan Talluri for their Revenue Management book.

3) Peter Bell of the University of Western Ontario won the INFORMS Prize for the Teaching of OR/MS Practice. Peter has worked a lot on cases in OR/MS.

There were a number of other prizes. I am sure the INFORMS Prize web page will have these shortly.

Luk Van Wassenhove and IFORS Distinguished Lecturer

2005-11-13T18:01:00.000-05:00

Luk Van Wassenhove was the IFORS Distinguished Lecturer at this year's INFORMS conference. Here he is receiving congratulations from Tom Magnanti (right), President of IFORS.

Luk spoke on "Closed Loop Supply Chains: Past, Present, and Future". Closed-loop supply chains are those where the supply chain bringing goods from consumers back to suppliers is also important. Luk gave an interesting historical perspective on this rather young field. He suggested that the field has gone through 5 phases:

1) Technical remanufacturing. Research into how to best remanufacture/resuse returned items, with little regard to how they come back or where they go after remanufacturing.

2) Valuing reverse logistics. Research and interest in how items coming back to a supplier can create value for that supplier. These models are more market driven than just waste stream recovery, and address the front end acquisition of items.

3) Coordinating decisions, bringing the forward supply chain together with the reverse supply chain. Once the magnitude of the problem is realized, the reverse chain impacts the forward chain, and vice versa.

4) Closing the loop, with dynamic decisions over the lifecycle of products. One aspect of this is the need to spend money to make money. Consider a "recycled" computer: one that is only a few weeks old is much more valuable than one that is months old. In such a case, investments might need to be made to increase the speed of the reverse supply chain.

5) The final phase of research, which perhaps should have been the first one, is "Is there a market"? While this area has increased in academic stature, and there are visible, but isolated, examples in practice, how can these insights be embedded in real firms. This brings in issues of accounting (how should returns be valued) and marketing (how should cannibalism be handled between original and remanufactured products)?

This was an ideal plenary session: broad, understandable and interesting.

Heading off to San Francisco ...

2005-11-11T15:42:00.000-05:00

for the INFORMS Conference (originally planned for New Orleans). US Airways cut back their direct flights from Pittsburgh, so it is through Minneapolis I go. I'll try to post some of the interesting things I see at the conference (if I can get out of the bar long enough: see my comments on social capital below).

Thoughts on fun things to do in San Francisco? I think blues is on the agenda for Saturday evening.

The Community of Operations Research

2005-11-10T11:32:00.000-05:00

For the past three or four years, I have given a talk at the INFORMS Doctoral Colloquium about the importance of social capital in a successful career. This talk is based on the book Bowling Alone by Putnam which argued that society (particularly US society) is becoming more detached, with fewer people engaged in the sort of interactions that lead to social capital. I think this issue is particularly important to OR people, since most of our best work comes by spanning boundaries, working with people in other fields in order to advance the other field while invigorating OR.

Some argue the web creates communities. I don't think that is really true. The number of true, ongoing communities seems pretty small. One group I know if is a mailing list on an author I adore: Patrick O'Brian (the movie Master and Commander was based on his work). This is an active mailing list that has been around for a decade. Even for this "community", the number of people who are active for more than a couple of years is astonishingly small, which suggests to me a lack of a true community. So is the technology too limiting or will face-to-face always matter?

Web Resources, then and now

2005-11-08T05:47:00.000-05:00

Wandering around the web, I came across a site that had copied my web page on pointers in Operations Research from 1994, presumably to avoid the then-slow cross-Atlantic downloads. It is stunning to remember what life was like pre-web. That page has about 50 pointers, about half of which were "ftp" or "gopher" (a http/html precursor). And I think that page was pretty complete! Compare that to the current INFORMS Resources page which has about 1500 pointers (100-200 of which are broken, but I'm getting to those) and is by no means complete.

I've been thinking about the value of these resource collections in the age of google. I spend a fair amount of time with the Resources page, but even I, when looking for something in OR, start at google. I think Resource pages are useful to get a handle on an area, and I am glad we have one for OR, but it certainly isn't the critical page it was pre-google.

Blogging

2005-11-04T16:25:00.000-05:00

It's been about a week that I have been keeping this blog, and so far I think it has gone well. It is nice to see the activity (I have opened up my sitemeter so you can check out the stats as well): there's about 20 visitors a day, and people are clicking around to explore, so many are staying for some time. Not many comments, though: I must attract shy visitors! Comments, of course, are welcome: feel free to comment on an individual post or on the blog in general. Easy enough to do: just click on the number of comments associated with an entry, and you get a chance to both read the comments and to add one of your own.

Warranties and Inventory

2005-11-04T16:01:00.000-05:00

Jay Swaminathan from University of North Carolina was visiting us today. He gave an interesting talk about how to set inventory levels when warranty replacement is a significant issue. This paper really hit a chord since I am working on my 5th(!) iPod. It seems without fail that my iPod fails after 3 or 4 months, requiring a return shipment and then a new iPod. The only good aspect of this is that the warrantee is reset, so an iPod originally bought in July 2004 is now warrenteed until November 2006. Who needs extended warrantees!

In any case, the paper (Jay together with Wei Huang and Vidhyadhar Kulkarni) made a couple good points: first, for fairly realistic data (they are working with a real, unnamed company), ignoring the warrantee needs in setting inventory can lead to pretty high stock-out charges. The second, less obvious but perhaps more important point, involved some new technology the company was planning to invest in. The company was going to put in a system whereby they would get detailed information on when an item was sold (and which item), rather than the aggregate sales values it was getting. This would give the firm an accurate distribution of the actual ages of the items in the field, rather than just the total numbers. It turns out that there was very little value in the more detailed distribution: aggregate information worked out almost as well. A good example of the value of analysis before making significant investments.

OR Exhibits

2005-11-02T21:20:00.000-05:00

I just got back from Washington, where a friend of ours, a scientific illustrator, had an opening for his work at the AAAS. It is a very impressive show, with a mix of illustrations of insects, plants, dinosaurs, and extinct mammals. The attendees of the opening were a real mix. Some had a scientific background, but most were enthusiastic amateurs.

It is too bad that OR doesn't lend itself to this sort of amateur interest. Martin Gardner's Mathematical Games column (and some of his successors) did appeal to the nonprofessional, and often had a strong OR flavor (that's how I got my start). But having an exhibit, attracting a mix of people, seems unlikely.

The closest we come to this is some of the optimization art done by Robert Bosch of Oberlin (I am sure there are others, and I would like to hear about them). Bob works in dominoes, traveling salesman tours, and many other media to create art through optimization. See, in particular, his site dominoartwork.com for samples of what he does.

OK, that makes two things I want to do since I started this blog: solve world hunger through improved logistics and have an opening at a prestigious museum. Looks like this blog is going to cause more problems than it solves!

Gary Lorden at INFORMS

2005-10-31T05:39:00.000-05:00

Most of the time, I can recognize the plenary speakers at INFORMS conferences, at least by name. The INFORMS San Francisco (nee New Orleans) conference has a guy named Gary Lorden speaking. Gary Lorden? Who the heck is he?

It turns out Gary is the mathematical advisor for the TV show Numb3rs, a crime show whose solution is generally based on mathematics of some sort. I found a review of one of his previous lectures: it sounds like it will be a blast! All the more reason to stay through Wednesday in San Fran.

OR in Africa

2005-10-29T09:30:00.000-04:00

There have been a couple of things I have seen recently highlighting OR in Africa. The first was a presentation by Luk Van Wassenhove on humanitarian logistics (here is an article Luk, David Kaatrud and Ramina Samii wrote about the UN Logistics Centre). While not limited to Africa, that region is certainly a key area. Humanitarian logistics offers a tremendous mix of organizational and technical challenges, not the least of which is coping with the sheer number of governments, NGOs, and other organizations, all with different objectives and requirements.

An article in the October OR/MS Today by Jonathan P. Caulkins, Emily Eelman, Minoli Ratnatunga and David Schaarsmith talked about a conference in Africa, the Operations Research Practice in Africa conference. Held in Ouagadougou, Burkina Faso, this conference looked at opportunities for real-world problem solving using OR to address Africa's issues. The summary brings up some interesting ethical issues (should OR be used to help repressive regimes?) and some area-specific OR issues (particularly the non-routine, non-replicable nature of crisis handling).

IFORS is holding its 2008 international conference in Africa: Sandton, South Africa to be specific. I'm traveling there in February to check out sites and speak with the local organizers. It turns out to be easier to get there than I thought, with direct (one stop for fueling) flights from JFK, Dulles, and Atlanta. I am also going to spend a few days in Capetown.

The issues brought up in these papers do make me wonder if working at scheduling professional sports leagues (my own current research) is the most valuable thing I can do with my life!

Robust Optimization

2005-10-28T16:29:00.000-04:00

Dimitris Bertsimas gave a talk here today on robust optimization. One question he asked was (paraphrasing) "What do you do when reality refuses to match up to the model?", which I think is a great question. So much of what we do seems to be fragile (think cascading effects of a snowstorm in Chicago stranding travelers in Miami) when we know that are models are based on data that is only an approximation to reality. Robust optimization (roughly, optimizing with an assumption that no more than a certain number of data points are wrong, and each is wrong by no more than a fixed amount) is one way to attack this. Stochastic optimization is another. I am not sure we have found the right method yet (though Dmitris' work is extremely impressive!).

Applications of Operations Research

2005-10-28T03:37:00.000-04:00

Roger Grinde of the University of New Hampshire put together an excellent blog on Applications of Operations Research. No updates since May. I hope it is a temporary haitus, since it is a great resource.

Silly Operations Researchers

2005-10-27T22:42:00.000-04:00

There is a thread on alt.folklore.urban that begins with the classic OR story of looking for places to increase shielding on planes in WWII: analysis of where holes were on planes was somewhat skewed by being limited to those that returned. This then goes on to other analyses: first a researcher concludes, based on prison interviews, that people of low intelligence commit crimes. This is updated to conclude criminals of low intelligence go to prison. Further updates suggest people (not necessarily criminals) of low intelligence go to prison. Interesting thread!

Recognition for Constraint Programming

2005-10-27T21:23:00.000-04:00

From the AAAS:

Professor Eugene C. Freuder, the Director of the Cork Constraint Computation Centre in the Computer Science Department of University College Cork has been elected a Fellow of the American Association for the Advancement of Science (AAAS). He is one of only 14 new Fellows elected this year in the Information, Computing, and Communication section of AAAS, out of a total of 376 new Fellows. AAAS is an international non-profit organization dedicated to advancing science around the world. Founded in 1848, AAAS serves some 262 affiliated societies and academies of science, serving 10 million individuals. The 2005 AAAS Fellows were announced in the 28 October issue of the AAAS journal Science. Science has the largest paid circulation of any peer-reviewed general science journal in the world, with an estimated total readership of one million.

CORS/Optimization Days 2006

2005-10-27T13:56:00.000-04:00

CORS 2006 in Montreal has a very impressive group of invited speakers:

- Teodor Gabriel Crainic, École des sciences de la gestion, Université du Québec à Montréal
Planning Models for Transportation in the Electronic Age
- Egon Balas, Carnegie Mellon (IFORS Distinguished Lecturer)

- Jack Edmonds (no web page, but here is a description of some of his work)
Existentially Polytime Theorems

- Ralph E. Gomory, Alfred P. Sloan Foundation
Thoughts about Integer Programming

- Adam N. Letchford, Lancaster University
Semidefinite Programming and Combinatorial Optimization

Definitely some impressive people there!

October Job Listings

2005-10-27T09:38:00.000-04:00

OR/MS Today's October issue is one of the big ones for job postings, and it looks like the market is pretty good these days. Lots of jobs both in business schools and in IE Departments. Good schools too: Georgia Tech, Michigan, Duke, Texas A&M, Stanford, SMU, Washington University and the University of Washington (you would think they would be closer geographically), Cornell, UT Austin, MIT, Berkeley, Virginial Tech, and many, many more. It does look like the business schools want "operations management" rather than pure "operations research". Still, there are some "management science" jobs in business schools open. I'd be interested in hearing from those on the market how supply and demand seem to match up.

INFORMS San Francisco

2005-10-26T16:09:00.000-04:00

Due to the hurricane, the INFORMS Meeting in November has been switched from New Orleans to San Francisco. It amazes me that a three thousand person meeting can be switched with such apparent ease. I am chairing the 2006 meeting in Pittsburgh: we have been working and planning on things for 2 years now. The thought of having to change everything three months before the conference is very scary. There is a great article in the October, 2005 issue of OR/MS Today on the planning for the switch (it wasn't as easy as it looks). We almost ended up in Kansas City (which would have been OK, but I prefer SF).

Welcome to the ORB

2005-10-26T15:53:00.000-04:00

Welcome to Michael Tricks Operations Research Blog (ORB). At the moment, this is a non-advertised blog to see if this is something I want to continue with. With this blog, I plan to chat about happenings in the world of Operations Research.

A few words about me: I am a past President of INFORMS (The Institute for Operations Research and the Management Sciences) and am currently a Vice President of IFORS (the International Federation of Operational Research Societies). A long time ago, I created Michael Trick's Operations Research Page, which eventually became the INFORMS Resources Page. I was also the founding editor of INFORMS Online.

For the past eight years, I was President of the Carnegie Bosch Institute for Applied Studies in International Management, but my time is up, so I am looking for other things to do. Starting January, I will be an Area Editor for the journal Operations Research, responsible for the "OR Forum": articles on controversial and/or important issues in operations research. This blog is part of some thoughts I had for how to make that Area be relevant and interesting.

So, let's get this show on the road, and see what happens.