Category: Blogs and Web

Yet Another Name for Our Field

I was wandering through the Internets and came across a new blog from Palisade.com, makers of @RISK and other software. It was a nice, relevant blog with some good stories, particularly on Monte Carlo simulation. I was taken aback by the name of the blog, however: “Operation Research”. I was a little confused for a bit and had to check back with my own blog to be sure that it is “Operations Research” normally in the US. In much (but not all) of the rest of the world, it is “Operational Research”. I am off to Bonn in a couple of days for the EURO meeting. During part of my time there, I will be attending board meetings for IFORS, where I try hard to use the term “Operational Research”.

But “Operation Research”? That just sounds wrong. It is hard to see how often that phrase occurs on web pages, since Google does some correction for you, but a search does show that it occurs, though often as a clear misspelling. I am not sure it is an improvement, but does represent something that could be used when the “operations/operational” conflict gets too much.

Grumpy Wikipedians

My experience with Wikipedia has been mixed, at best, particularly in the Operations Research area. Arguing with some non-OR person about what OR is has its advantages: it forces a rethink of one’s beliefs. But it can be frustrating, since it is not clear who you are discussing changes with or what their goals and interests are. And, if you are active in societies, blogs, and so on as I am, opportunities for “conflict of interest” abound. So a couple of years ago I decided to not edit operations research aspects of Wikipedia, leaving it to others. I am grateful that others work to make the entry better, though it is still far, far too historically based for my happiness.

My mixed experience with the (non-OR) denizens of Wikipedia might not have been unusual. Francisco Marco-Serrano of the blog FM Waves pointed me to an article in New Scientist about grumpy and close-minded Wikipedians:

Disagreeable and closed to new ideas – that’s the picture that emerges of contributors to community-curated encyclopaedia Wikipedia from a survey of their psychological attributes.

Led by Yair Amichai-Hamburger of the Sammy Ofer School of Communication in Herzliya, Israel, a team of psychologists surveyed 69 Israeli contributors to the popular online encyclopedia, comparing them with a sample of 70 students matched for age and intensity of internet use.

…

As Amichai-Hamburger expected, the Wikipedians were more comfortable online. “They feel the internet is a more meaningful place to them,” he says. But to his surprise, although Wikipedia is founded on the notion of openly sharing and collecting knowledge as a community, they scored low on agreeableness and openness.

“Wikipedia in a way demonstrates the spirit of the internet,” Amichai-Hamburger says. “People contribute without any financial reward.”

Amichai-Hamburger speculates that rather than contributing altruistically, Wikipedians take part because they struggle to express themselves in real-world social situations. “They are compensating,” he suggests. “It is their way to have a voice in this world.”

Of course, the same might be found out about blog writers!

New Blogs and Welcome Graham!

On my sidebar, I try to keep track of all the operations research oriented blogs. There are still few enough that I think I can keep a complete list (even allowing for a pretty broad view of operations research). The advantage of being on the list is that new posts on each of those blogs show up on my “From the OR Blogs”. Further, many of the posts are fodder for my twitter stream, which reaches literally dozens of people! So, if you are posting in the blogORsphere, and I don’t list you, please let me know: I am not meaning to ignore you (though if you don’t post for 2 months, you go onto my “inactive” list, so keep the posts coming).

On that note, let me welcome Graham Kendall, who has begun Research Reflections. Graham runs the MISTA conference series that will take place next in Dublin in August. Graham is a good friend of mine, even if he did dump me during a conference, forcing me to listen to a very boring lecture on art when I could have been enjoying a pint with him in a congenial pub (there were extenuating circumstances: my attention wandered during the critical “let’s get the heck out of here” moment). So I have forgiven him that, and recommend to you both his blog and the MISTA conference (of which I am part of the advisory committee, so I have some biases here).

And please check out all of the OR Blogs, and the “From the OR Blogs” in the sidebar (both of which appear if you go to the main page of this blog). There is a lot of great stuff out there.

Punk Rock OR Blogger Addresses Aviation Security

Laura McLay, author of Punk Rock Operations Research, has an interesting research paper out on identifying risky airline passengers in order to increase security for them. It is costly (both in money and in passenger inconvenience) to subject everyone to the highest level of screening. So who should be screened, given limited screening resources? Laura worked with Sheldon Jacobson (who is frequently seen in this blog) and Alexander G. Nikolaev on this problem, and they published their work in the June 2009 issue of IIE Transactions (IIE Transactions, Volume 41, Issue 6 June 2009 , pages 575 – 591).

From the VCU Press release:

Changes in aviation security policies and operations since the Sept. 11, 2001, terrorist attacks have resulted in every passenger being treated as a potential security risk, with uniform screening of passengers and their luggage. Screening all passengers the same way is costly and inconvenient for air travelers, according to the research, published in the June 2009 issue of “IIE Transactions.”

“We set out to find a real-time screening methodology that considers both available screening resources and the necessity of being robust in assessing threat levels,” said Laura A. McLay, Ph.D., an assistant professor in the VCU Department of Statistical Sciences & Operations Research. “This paper provides methodology to quickly determine which passengers are high-risk and who is low-risk and screen them accordingly,” McLay said.

Here is the full abstract:

Designing effective aviation security systems has become a problem of national concern. Since September 11th, 2001 passenger screening systems have become an important component in the design and operation of aviation security systems. This paper introduces the Sequential Stochastic Passenger Screening Problem (SSPSP), which allows passengers to be optimally assigned (in real-time) to aviation security resources. Passengers are classified as either selectees or non-selectees, with screening procedures in place for each such class. Passengers arrive sequentially, and a prescreening system determines each passenger’s perceived risk level, which becomes known upon check-in. The objective of SSPSP is to use the passengers’ perceived risk levels to determine the optimal policy for screening passengers that maximizes the expected number of true alarms, subject to capacity and assignment constraints. SSPSP is formulated as a Markov decision process, and an optimal policy is found using dynamic programming. Several structural properties of SSPSP are derived using its relationship to knapsack and sequential assignment problems. An illustrative example is provided, which indicates that a large proportion of high-risk passengers are classified as selectees.

As the New York Times reports, the TSA is upgrading its security by requiring things like real names (not nicknames) on tickets. Perhaps operations research can offset some of the inconvenience of these “upgrades”.

Advertising Operational Research (but maybe a few updates are in order?)

The Operational Research Society (the U.K. equivalent of INFORMS) has a website about operational research (the U.K. equivalent of operations research) aimed at students and teachers called Learn about OR. This makes a great adjunct to the INFORMS site, the Science of Better, aimed at business. Lots of good examples and good advice about getting into the field.

For portions, however, the site shows the tone-deafness that we in OR often show. Some of the examples might be a little more relevant to a 50-year-old rather than a teenager. Consider the example aimed at 11-14 year olds “OR Inside Your Holiday Snaps”:

It’s highly unlikely that, while you were snapping your holiday photos on the beach, you stopped to think, ‘Is there O.R. inside the film in this camera’? But, in fact, there is!

Photographic film is manufactured in rolls about 6km long by 1m wide, which have to be cut up into complex patterns so as to produce a wide variety of products. The problem of deciding how to cut the rolls is very complicated

What a great example: cutting photographic film is a wonderful example leading to column generation approaches and other advanced math programming methods. Too bad the average twelve year old hasn’t ever seen photographic film. I look forward to examples of fitting music onto cassette tape cartridges and optimal horse rotation for mail delivery.

Despite this cavilling, it is a good site, and the sort of site the world needs more of. There is even a introductory video that covers the range of OR (with instructions for downloading to an ipod).

Thanks Dawen, of ThinkOR, for mentioning the site in a somewhat different context.

Advice to Doctoral Students

Noah Snyder, a doctoral student in mathematics at Berkeley, has a wonderful post on how to be a successful doctoral student (I lost track on where I saw this:  if it is from an OR blog, please let me know so I can give credit Thanks to Yiorgos Adamopoulos for his tweet on this).  While there is an emphasis on the situation in mathematics, I think the advice he gives is great (for the most part).  His thoughts revolve around the topics:

  • Prioritize reading readable sources
  • Build narratives
  • Study other mathematician’s taste
  • Do one early side project
  • Find a clump of other graduate students
  • Cast a wide net when looking for an advisor
  • Don’t just work on one thing
  • Don’t graduate until you have to

I particularly like his “build narratives” advice.  Every good piece of research has a story behind it.  Why is this research being done?  How does it fit?  Why should people care about this research (hint:  “The literature has a hole which I have now filled” is not a particularly evocative story)?  Once that story is found, research directions are clear, and the whole enterprise takes on a new life.  Note that the narratives are not the same as a popularization (like, say, a blog posting);  the example Noah gives is pretty technical:

In the 80s knot polynomials went through the following transition. First people thought about towers of algebras, then they replaced those with skein theory, then they related those to quantum groups. Attempts at categorification has gone backwards through this progression. First Frankel and Crane wanted to categorify quantum groups, when that proved difficult Khovanov instead categorified the skein theory. Finally, in Khovanov’s HOMFLY homology paper he went all the way back to categorifying towers of algebras and replacing them with towers of categories.

There is a narrative there, and it is one that will resonate with the research audience.

About 22 years ago, when I was a doctoral student trying to finish my dissertation, I had a terrible time putting things together.  I had lots of papers (it was a great time to be a doctoral student at Georgia Tech:  lots of great young faculty to work with) but I couldn’t put it together into a dissertation.  I remember getting snowed in during a rare Atlanta snowstorm and sitting down with a stack of index cards, on which I wrote all that I knew about or wanted to explore further.  I spent the next day or two shuffling the cards and putting them in different groupings and orders.  Out of that, a story finally appeared.  I don’t think it was a great story (the title of my dissertation was “Networks with Specially Structured Side Constraints”), but it was enough of a story to shape the disseration and provide a research agenda for the first years after graduation.

I see a lot of students who present work who don’t go beyond “My advisor told me this was a good problem”.  I think thinking about the narrative would do a lot of us good.

The only piece of advice I would disagree with from Noah’s post is the last one, where he suggests delaying graduation.  This may be forced by his field, which is extremely competitive, but I strongly disagree with that advice in operations research.  In general, I think students should get what they can out of a doctoral program, and push themselves to move on.  Our doctoral students make perhaps $20,000 a year or a bit more:  a comfortable graduate student living, of course.  But faculty salaries will be many times that amount, and even postdocs will pay better.  Don’t stay in school hoping for that one more paper that will put you over the top.  If you have only one more paper in you, you won’t last in this field anyway.  If you have more than that, do them at the next phase of your career.

I am not suggesting rushing through your doctoral program, but once you finish your fifth year here at CMU (we admit students from the bachelors degree, and give a masters degree along the way), we’d really like for you to think about moving on, and I think that is a pretty good general outline.

If you are a doctoral student, or a researcher of any age for that matter, I highly recommend reading Noah’s comments.

Optimal Cleaning Paths

Yesterday I twittered:

Doing too much operations research. Spent more time figuring out optimal mowing pattern than mowing lawn.

roombaToday, I came across a picture of a Roomba’s path to clean the floor of an l-shaped room (through a number of sites, but I think I am referring to the original). I think I am a little more efficient in lawnmowing, but, then again, I know the shape of my lawn: Roombas figure out the shape dynamically. Interesting OR problem to come up with the optimal Roomba algorithm.

What Motivates Operations Researchers?

I was wandering through the Social Science Research Network (a place to which I don’t often go) and I checked out the top operations research papers. The most downloaded paper is by Martin Shubik on 50 years of operations research and game theory. This is an older (2001) paper but makes fascinating reading. I was struck by a paragraph on what motivates people in operations research:

This is illustrated by an event which happened to me at General Electric and another which happened to George Feeney at Stanford Research Institute. I was complaining to one of the vice-presidents that in spite of the fact that General Electric in the 1950s had hired a first class group of operations researchers, the management except for Harold Smiddy (Smiddy and Naum 1954 is still worth rereading) did not appreciate us. Jack McKitterick (the VP of marketing) replied that the trouble with the executives at General Electric was that they had not understood the basic motivation of the group they has hired. He said if they had to do it over again they would have paid us half as much but would have hired a special manager to stroke us and to go around telling each of us how smart we were. George Feeney’s experience at Stanford Research involved explaining what operations research was to one of their vice-presidents who reacted immediately. “I see”, he said, “operations research involves utilizing big minds to work on small problems.”

Ouch. I’d argue with this, but I just spent two days developing an improved optimization approach to scheduling soccer games for five year olds.

INFORMS Practice Conference goes Web 2.0 Crazy!

The upcoming INFORMS Practice Conference has embraced new social networking technologies as no INFORMS conference has ever done. You have your choice of

  1. Blogging. A conference blog with a half dozen guest bloggers (including yours truly).
  2. Twittering. Just use the #ipc2009 tag
  3. LinkedIn. I’m not sure the value of a LinkedIn group, but I want to be part of the gang!

Let’s see, what’s left? Facebook? Club Penguin?

This makes a great experiment in what helps people best engage with a conference.

NSF on Twitter

Following up on my issues with twitter, (like why?), the National Science Foundation has its own twitter account.  What a great way to get word out about all the great stuff the NSF does!  This is something professional societies (like INFORMS) should emulate.  I don’t think my own life is interesting enough for an hour by hour update, but NSF is certainly interesting to follow.