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June 2010

May 2010

Whatever Numbers You Like

I loved the column "The Trouble with Rankings" by Carl Bialik at his Numbers Guy blog on the Wall Street Journal website. He gives valuable insights into the - occasionally very unscientific - way some of these rankings are obtained. 

Here are a few highlights:

  • Some magazines compute rankings in various categories and then add those rankings together, but if the range of results is very narrow, a city ranked 1st and a city ranked 100th might have much more similar profiles than the rankings suggest.
  • Some magazines pick the wrong explanation for the data. For instance, "[t]he ranking [of American drunkest cities] counted arrests for driving under the influence against cities, though they could also reflect stepped-up enforcement of laws."
  • US News hospital rankings use a reputation category that dwarfs all the other metrics, but "[h]ospitals with national reputations tend to win all available points in this category, giving them such a formidable lead that they typically top the rankings even if their scores on objective outcomes aren’t as strong... One result is that Boston’s Dana-Farber Cancer Institute ranked fifth for cancer treatment last year despite lagging behind many hospitals ranked below it on every measure besides reputation."

Bialik's print column offers an even more detailed and sobering account of the problems with rankings.

For more readings about numbers, another of Bialik's posts describes the difficulty in counting illegal immigrants in Arizona and the unverifiable assumptions that underlie those figures (the post is again a follow-up on one of his print columns, which has an interesting graph of the number of illegal immigrants as a percentage of state population per US state in 2008.)

In particular, studies "assume that about 10% of illegal immigrants aren’t counted in these surveys. But that figure largely is based on a 2001 survey of Mexican-born people living in Los Angeles," which - as its author emphasizes - should not be used to count immigrants outside LA County. Bialik also discusses the issues in using the number of border-patrol apprehensions as proxies.

The award for best quote of the day goes to the director of the Census Bureau, who stated: "We would like to do estimates that have the smallest number of assumptions we can’t test." A worthy goal indeed.

Joe Girardi is an IE

Back in January, the revamped Harvard Business Review inaugurated an interview series, called Life's Work, on the last page of the magazine. The June issue features Joe Girardi who - in case you don't follow sports or don't live in the US - is the manager of the New York Yankees. Here is how it starts.

HBR: "You're famous for being information-driven and analytical in your approach to managing."

Girardi: "I love numbers. You can never give me too many numbers. I believe they tell a story, if you have a large enough sample." (I paused there the first time I read the interview and wondered about the last time I read something that smart and accurate about numbers in the mainstream media. I was certainly surprised these words would come from a baseball manager rather than, say, an academic.)

Girardi adds: "I have an industrial engineering degree [insert rim shot here!] - a degree in problem-solving, basically."

Sure enough, it turns out Girardi graduated from Northwestern University with a Bachelor of Science in Industrial Engineering. I'd love to take his definition of an IE degree and apply it to operations research: a degree in problem-solving... That has a nice sound to it.

The online version of the article, available in full and for free, even has material that didn't make it into print. You can read it here.

C.K. Prahalad

I was saddened to learn in the latest Harvard Business Review of C.K. Prahalad's passing at the age of 68 this April. His columns were one of my favorite items in HBR, especially the one entitled "The Responsible Manager" which appeared in the January issue. (I wrote about it here, where I singled out this line: "Understand the importance of non-conformity... Leaders have to venture into uncharted territory, so they must be able to handle intellectual solitude and ambiguity.")

Prahalad, a professor at the University of Michigan (Ross School of Business), was a highly influential management thinker and expert in corporate strategy, best known for "populariz[ing] the idea that companies could make money while helping to alleviate poverty" (quoted from his New York Times obituary). His best-known book, published in 2004, was indeed titled: "The Fortune at the Bottom of the Pyramid: Eradicating Poverty Through Profits."

Additional resources:

  • Commemorative section set up on HBR website. 
  • Prahalad's HBR author page: "He won the McKinsey Prize four times for the best article in Harvard Business Review and received honorary doctorates in economics (University of London), engineering (Stevens Institute of Technology), and business (Tilberg, The Netherlands and Abertay, Scotland)," among many other accomplishments.
  • Obituary in the Washington Post.
  • Obituary in the Wall Street Journal.

Lehigh Commencement

Today was Commencement at Lehigh. The weather was cloudy but, in a sharp improvement over two years ago, the rain only fell after the ceremony had ended (in 2008 the weather was frigid and marked by a downpour of rain in the middle of the ceremony - in particular the College of Engineering students, who receive their degrees last and had been waiting to get their diplomas, were completely drenched). In an improvement over last year, it was not even cold. At this rate, next year we might see a little bit of sunshine.

Elie Wiesel gave a powerful speech for the Commencement address, where he urged graduates "not to become indifferent to the suffering of others, lose their passion for learning, or allow the lessons of the brutal 20th century to be forgotten by future generations". He also mentioned that "[l]ife is not made of years, but of moments," a theme that will have resonated with the seniors, and emphasized that "[y]ou cannot allow yourself to become indifferent... whatever you do in your life, indifference is never an option."

Having gone through two graduation ceremonies at MIT where Commencement lasts four hours (or at least did when I was there, at a time where we had neither iPods nor Blackberries to keep us occupied), today's ceremony seemed of a good length: not too long, but long enough to emphasize the importance of the moment. It started a few minutes after 10am, students began to receive their degrees shortly after 11am and it was all over around half past noon.

I enjoyed seeing the ISE seniors graduate, especially the students whom I first met four years ago during their first week at Lehigh, in my capacity of academic advisor for the freshmen. 2006 was the first year where I served in that role, so I remember that group of students particularly well. It seems fitting somehow to have met them at Convocation and now watch them put an end to their years at Lehigh. (Special round of good-mornings to Jim Z. and JJ, both of whom I advised as freshmen and whom I saw walk across the stage today.)

Life after graduation can be several orders of magnitude more exhilarating than college, for people who savor the memories of the good times but don't wallow in nostalgia (it can be more uncomfortable too sometimes, but in the end much more exhilarating) and I am sure many successes and accomplishments await the Lehigh Class of 2010 beyond Bethlehem.

Words of Wisdom

It was a big day today at Lehigh with the doctoral candidates receiving their hoods at Zoellner Arts Center (the hood is a garment worn over the cap and gown that distinguishes Doctors from Bachelor and Master recipients), and it will be an even bigger day tomorrow morning with Elie Wiesel giving the Commencement address at Lehigh's Goodman Stadium. In line with the Commencement spirit, I'd like to link to a wonderful op-ed column by former Major League baseball player Doug Glanville, which he wrote for the New York Times back in October.

While much is made in the business literature about the role of mentors on individuals' development, Glanville writes about the importance of a particular detractor had on his ultimately highly successful career. This man - one of Glanville's managers in Triple-A Iowa - "seemed to revel in doing everything he could to break [him]" because he never forgave Glanville for an argument they had after a game. He "never let [him] work on one potentially productive part of [his] game, base-stealing", "omitted one of [his] ongoing hitting streaks from [his] player report" and the list goes on. This experience was critical in Glanville's meeting someone who became his sponsor and gave him the opportunity to shine.

One could sum up Glanville's message as: be grateful for your detractors, because you often want to prove them wrong more than you want to prove your supporters right. The sting of their criticism pushes you to action in ways cheerleaders can't.


Today, I received the official letter from the Provost stating that the Lehigh University Board of Trustees had voted to promote me to the rank of Associate Professor with tenure. It doesn't come as a surprise, since the signals have been overwhelmingly positive at every stage of the year-long process, but it is nice to have this behind me. Of course none of this would have been possible without my fantastic students, in particular Gokhan Metan and Ban Kawas, now PhDs, and Phoebe Lai, my undergraduate researcher, as well as my current doctoral students, research assistants and the students I have had in class. I continue to be amazed by the student quality at Lehigh, including at the undergraduate level. (I make them work hard, but they can handle it.)  I am thrilled that Lehigh University values my accomplishments so far in both research and education and hope to make even more significant contributions in the years to come.

And now, time to celebrate!


The data-driven life. This is the title of an article in the New York Times Magazine, about some people's obsession with data and the technological changes that have made this trend possible, from the cell phone to the speedometer. The journalist appears to find the systematic collection of data to determine, say, whether caffeine helps or hinders someone's concentration, frankly extreme. "These men all know that their behavior is abnormal. They are outliers. Geeks. But why does what they are doing seem so strange? In other contexts, it is normal to seek data." and later: "We tolerate the pathologies of quantification — a dry, abstract, mechanical type of knowledge — because the results are so powerful."

Also: "This is how the odd habits of the ultrageek who tracks everything have come to seem almost normal." What a flattering portrait of data-oriented people. Comments tend to be scathing toward "geeks" too; see for instance Comment #5: "Seven pages devoted to the lifestyle habits of nerds? How about two pages being able to cover it? These guys turn inward and monitor themselves excessively because they have too much time and too little going on in the real world outside their cubes. OK for them, but kind of sad." What is sad is the distorted picture the article paints, as if using numbers to test hypotheses was a deviant behavior. (I don't collect data, but I can imagine how the people named in the article must have felt when they saw the story in print.)

The journalist and the commenters divide the world into nerds and non-nerds, with rigid boundaries, but a lot more people than just nerds use Facebook, Twitter, and the other networking sites the article's author mentions. What makes this trend interesting, in my opinion, is that we have reached a stage where people with no interest in the intricacies of collecting data can buy a device, such as a Garmin running watch, that will gather and analyze it for them. Also, companies - from brick-and-mortar retailers to websites to EZ-pass providers on the highway - are already collecting large amounts of information about their users; for instance, supermarkets' reward cards give customers discounts in exchange for an exact list of what they purchased and when they purchased it. This allows retailers to finetune inventory levels and determine when to stock new items. The data is already out there; people are living data-driven lives now, even if they are unaware of it. The real question is: do they want to use this information in a proactive manner, or are they content letting a company use their data to make money off them?

DARPA's new director. The New York Times has an article here about the new director of the Defense Advanced Projects Research Agency (DARPA), Regina Dugan. She has a PhD in mechanical engineering from Caltech and is the first woman to take the helm of the agency. Recently, she played a key role in developing the Darpa Network Challenge, a balloon hunt that required the use of social networks. The contest was won by a team from MIT, who was "the first of 4,300 entrants to find 10 red weather balloons placed at undisclosed locations across the United States. They located the balloons in just under nine hours using social-networking technologies." (A related article from MIT News is available here.)

The NYT journalist points out that "Darpa has been criticized as focusing too closely on “deliverables” for the nation’s soldiers, in the process forgoing the high-risk technology gambles that originally were the agency’s trademark"; Dugan must now address that imbalance. This is her second stint at DARPA. Her first one, in the 1990s, saw a small international incident when the State Department wrongly declared her missing in action during a mine-clearing expedition in Mozambique. That woman's personality is larger than life, which given the task ahead is just as well.

NOVA's Secret Life of Scientists. PBS program NOVA has a web-online series "that shows what happens when the lab coats come off." MIT's Dava Newman, a professor in aeronautics and astronautics who designs spacesuits for NASA's future lunar missions, discusses her work here. My favorite video profiles Cornell nanoscientist Rich Robinson, who is also a talented photographer. His work has led his local library to create a series called ‘The Art Behind the Scientist.’ From this blog post: "The series will include the work of scientists who are also artists. They will exhibit their work and present a talk or workshop about it."

Six years into this job, I remain amazed by the number of scientists and engineers with a right-brain passion. It is so easy for students to forget their teachers have a life and interests beyond the classroom, as if everyone became one-dimensional as soon as they entered the workforce. My own passion is writing (surprise!) but photography is an activity I know a lot of left-brain people share, including one of my former professors, Dimitri Bertsekas. You can see some of his pictures at the bottom of the webpage I link to. Other NOVA videos describe the work of Nate Ball, 2007 Lemelson-MIT Student Prize winner who invented the Ascender rope-climbing device (a rope that pulls soldiers and rescue workers upward very fast in emergency situations), climate scientist Gavin Schmidt, geologist Alexandrea Bowman, and more.

Links I Like

Politicians' honors theses. Someone at Slate wrote a thoughtful article about why politicians' writings as college students can't be expected to reflect their thinking thirty or forty years later. Seniors only have a few weeks to select a topic, often based on the recommendation of the professor who will supervise the research as well as their own interests at the moment. The research has to generate new results or analysis, which precludes safe choices. Because students want to stand out from the crowd, they often take harsher and more controversial stances than necessary - to their detractors' delight, decades later.

The journalist adds: "You then have a semester to write a 50-page essay—a task that would be difficult even without the added burden of classes, extracurriculars, and the intense hepatic demands of senior spring." (Those last few words get my vote as prettiest expression ever about senioritis.) But at least the hunt for incriminating documents has so far been limited to politicians. Now that employers routinely run job candidates' names through Google Search and students themselves leave a lot of their personal information on the web, we are only a few years away from more minor embarrassments when candidates for top management positions realize that their drunken comments with five exclamation marks never left the Internet.

It's never too late to graduate. Boston University recently held Commencement exercises for its Class of 1970. The graduation ceremony forty years ago had been canceled due to social unrest. (Final exams had been canceled too.) The New York Times writes: "President Richard M. Nixon had invaded Cambodia. National Guardsmen had gunned down students at Kent State, killing four and wounding nine. Young men still faced the draft. And this campus, like many across the country, was in turmoil, with strikes, sit-ins, building takeovers and fire-bombings." It seems incredible that no one had the idea to hold a makeup Commencement ceremony for decades. As a member of the Class of 1970 points out, "It was worse for the parents and the grandparents, many of whom are dead now and were robbed of that opportunity to see their child march across that stage." But of course nothing can come close to the shock of the Kent State massacre, which remains in the media spotlight to this day.

The little indignities of life. A NPR journalist writes about trying to hail a cab in Washington, DC, as a person of color. "The drama of getting a cab... is no better than it was more than a decade ago when actor Danny Glover made a public stand against New York City's taxi and limousine commission because he said five yellow cabs refused to stop for him in a single day because he is black." A fascinating insight into race issues in ordinary moments.

Hard-working vs smart. A Stanford researcher makes the case that people should not refer to intelligence as a fixed trait, as reported in the Chronicle Review. In particular, they should not praise their children for their intelligence, but rather their effort - this not only leads to happier children, but (more importantly) improved performance. What I found truly fascinating there was that other researchers could not validate her theories when considering children from less privileged backgrounds in their own studies. "One potential factor is that Temple [University in Philadelphia] is a less-selective institution than the colleges where the best-known previous studies have taken place. So differences among the Temple students' beliefs about intelligence might be swamped, for example, by differences in their baseline knowledge about how to navigate through college life."

Even more interesting: "students whose self-worth was tied to academic performance" were more likely to self-handicap by listening to distracting music during the test if they had been given a difficult sample question before the exam, leading them to believe the exam would be hard. People practice self-consistency (self-validating behaviors). If they believe they are innately smart and struggle with a task, they will avoid doing the task so that their inability to perform it does not conflict with their inner belief. If they want something but are afraid they will not succeed, they prefer to self-sabotage.

How math will save the world. (This is about a months-old New York Times article, but I never got a chance to write about the article until now.) In Chicago, the new chief officer of public schools, a former police officer and transit executive, hopes that statistical analysis will help identify "high school students with the highest risk of becoming involved the violence as victims, or even perpetrators". An "analysis of more than 500 students who were shot over the last several years [will be used] to predict the characteristics of potential future victims, including when and where they might be attacked."

While this seems like a tall order, and maybe a naive faith in statistical analysis, the preliminary conclusions of the mathematical analysis border on the usual, and useless, cliches. At least they match expectations. ("The students at high risk of violence, by statistics, are most likely to be black, male, without a stable living environment, in special education... and having a record of in-school behavioral flare-ups.") The schools' chief officer makes good points about trying to identify the most likely perpetrators and reaching out to them before they get someone hurt. He says: "We believe that if we can change the behavior of these 10,000 [most at risk] students, we’ll be able to make a significant difference in the level of violence in the city."

Industrial Engineering in Hospitals

The May 2010 issue of Industrial Engineer magazine, the monthly publication of the Institute of Industrial Engineers, has an article about the implementation of manufacturing practices in hospitals' operating rooms. It is co-authored by Lehigh's own Nick Kastango, who graduated last year from the Industrial and Systems Engineering department with a bachelor degree in Industrial Engineering. According to the short bio at the end of the article, Nick is now a strategic analyst at the Memorial Sloan-Kettering Cancer Center in New York, after a stint as an intern at the Lehigh Valley Health Network. (The other author, Steven Jagiela, is a lean coach with the Lehigh Valley Health Network.)

The article, unfortunately not available online, is entitled "Collaboration makes the process better." You can read an example of the "System for Partners in Performance Improvement" (SPPI) developed by the Lehigh Valley Health Network on its website. The Industrial Engineer article explains that "Throughout the network, SPPI lean coaches facilitate improvement efforts, including value stream analysis, projects, point kaizen and process kaizen events." (My non-IE readers might benefit from the Wikipedia definition of kaizen: "a philosophy or practices that focus upon continuous improvement of processes in manufacturing, engineering, supporting business processes, and management.")

The IE article also describes the use of Production Preparation Process (3P), which the Environmental Protection Agency (for some reason the highest search result on Google when you look up these terms) characterizes as "one of the most powerful and transformative advanced manufacturing tools... [which] focuses on eliminating waste through product and process design." There, the Lehigh Valley Health Network enlisted the help of B. Braun Medical, a medical supply company with expertise in lean techniques, which is headquartered in the Bethlehem area. The article then gives examples of changes  made following the 3P event, based on B Braun's advice, in particular with respect to the "picking" of instruments and supplies in preparation for a procedure.

Kastango and Jagiela provided a fascinating overview of how industrial engineering techniques can be applied in non-traditional settings such as hospitals rather than manufacturing plants. They also draw welcome attention to one of the success stories in the Lehigh Valley, "the largest employer in the region... the largest Level 1 trauma center in Pennsylvania... recognized as one of the US News and World Report's America's Best Hospitals and... one of Fortune magazine's 100 best companies to work for."