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August 2009

Paul Tseng

I have just returned from the ISMP conference, where Paul Tseng, a mathematics professor at the University of Washington in Seattle and MIT graduate, for whom I worked as a Teaching Assistant back in the Fall of 2002 when he was on sabbatical at MIT, was scheduled to give a semi-plenary talk on Tuesday. The conference committee has been publishing daily newsletters for the duration of the conference, and here is an excerpt from today's newsletter (also see this article dated August 25 from the Seattle Times, which provides similar information):

"Paul Tseng's Whereabouts Still Unknown.
The University of Washington has issued the following press release concerning Paul Tseng:

"University of Washington mathematics professor Paul Tseng has been missing since August 13 in a scenic mountainous region in Yunnan Province, China. Tseng was invited to China to participate in [a conference.] Prior to his appearance at the conference, Tseng, an avid outdoorsman and experienced kayaker, planned a kayaking trip on the Jinsha river. When he failed to appear for his presentation, conference organizers notified the local authorities in Lijiang. [...] Tseng was seen entering the Jinsha river August 13 near Jinganqiao, but there has been no contact with him since and his whereabouts remain unknown."

[...] Paul's many colleagues and friends at ISMP are distressed by his absence and he remains very much in our thoughts as we wait and hope for good news."

Rejecta Mathematica

The online version of the Economist has an interesting article about a new journal called... Rejecta Mathematica (Huddled Maths, July 29, 2009). From the article: "As its name suggests, the new journal publishes only papers that [...] have been previously submitted to, and rejected by, others." The Economist mentions several famous articles that initially suffered a rejection:

  • Paul Lauterbur's work on magnetic-resonance imaging, for which he won the Nobel Prize in 2003. See the Wikipedia pages on Lauterbur and MRI, which has become a common technique in radiology, as well as Lauterbur's 2007 obituary in The Economist and in particular the first sentence: "The whole history of modern science, Paul Lauterbur once joked, might be written on the basis of papers turned down by academic journals." The whole obituary is worth reading, but is available only to Economist's subscribers.
  • Peter Higgs's work on the particle that now bears his name, the Higgs boson, which has yet to be observed but is supposed to explain the origin of mass. See the Wikipedia pages on Higgs and his boson. In this interview with Times Online, Higgs explains why the paper was rejected back in 1964: "I hadn’t said enough to convince anybody that this was really important physics. So I added on some extra paragraphs." The journalist continues: "The revised article – still less than two sides of A4 paper — was accepted by an American journal, the Physical Review Letters at the end of August [after being rejected by the European Journal of Physics Letters]."
  • (This one is not mentioned in the article itself but in the comments.) The seminal option pricing model developed by Fischer Black and Merton Scholes, discussed in this Wikipedia page, was rejected by both the Journal of Political Economy and the Review of Economics and Statistics before finding a home, in a revised version, in the Journal of Political Economy. (Source: Advanced options trading by Robert Daigler pp.128-129, as shown on Google Books.)  

The author of the "Huddled Maths" article explains: "The serious aim [of Rejecta Mathematica] is to highlight papers that, although perhaps flawed, may still be interesting." I was a bit skeptical at first: a lot of papers are rejected during the first round of reviews; sometimes they have severe weaknesses, and sometimes they are simply not ready for publication at that stage but will be accepted once they have been revised. Breakthrough papers in particular might have been written in a rush so that their authors could submit them before a rival came up with the same idea; some reviewers have a low tolerance for that kind of behavior. When first drafts are not rejected outright, the reviewers often recommend a major revision. Is this worth a new journal?

Then I did look up the table of contents of Rejecta Mathematica and was surprised to see a name I knew: Stephen Boyd, a professor in Electrical Engineering at Stanford University with a long and distinguished track record in the field of convex optimization, who gave a plenary talk at the ISMP (International Symposium on Mathematical Programming) conference earlier this week and is the co-author of a popular textbook I use in some of my classes. His article in Rejecta Mathematica, co-authored with his student Siddharth Joshi, is on "subspaces that minimize the condition number of a matrix."

The most enjoyable part of the journal is that authors must submit an open letter describing the previous rejections. Joshi's and Boyd's is quite entertaining. In particular, they write: "The first rejection was based on the reviewers and editor noting that someone had written a paper that seemed to cover similar material. But a cursory reading of that paper, and ours, show that while the other paper shared a few key words with ours, the results were in no way related." And later: "We then submitted the article to another journal. In this case, the editor apparently did not even understand the result, which is stated very clearly, in completely standard, and elementary, mathematical language."

Maybe the real impact of Rejecta Mathematica on the field of mathematics will be to push for a better reviewing process in other journals.

I Am A Lawyer!

Well, not really. But it came to my department chair's attention that some students might have been using "smart pens" in class last semester; apparently, the new generation of smart pens is able to capture its user's writing (that can later be transferred to a computer and turned into a searchable document) as well as record what is being said in class. I thought this sounded far-fetched until I found a smart pen on, and it does indeed do all of the above, at least according to the product description. That is absolutely amazing.

The issue is that, while students are free to make copies of their notes and pass them around, recording other people without their consent is illegal in Pennsylvania. To use the technical jargon of this Wikipedia page on the telephone recording laws, Pennsylvania is one of twelve states that require all parties to consent to the recording for it to be legal; such states are called "two-party consent states" from the days where the wiretapping act focused on phone conversations, which only involved two parties. These states really should be called "all-party consent states" now. The other states and the District of Columbia are "one-party consent states", which means that people who are taking part to a conversation can record it without anyone else's knowledge. (There are some exceptions to those rules.)

The website of the Reporters' Committee for the Freedom of the Press has an insightful section about the legality of taping across the various states; the material is intended for journalists but contains useful information for other people too. A table summarizing the tape-recording laws is available here. The specific case of Pennsylvania is described here, although the webpage does mention the statute was set to expire in December 2008 and I am not sure if it was amended. It is likely that the Wiretapping and Electronic Surveillance Control Act remains on the books in one form or another. In particular, "[i]t is a felony of the third degree to intentionally intercept, endeavor to intercept, or get any other person to intercept any wire, electronic, or oral communication without the consent of all the parties. 18 Pa. Cons. Stat. § 5703(1)."

This is an awful lot of trouble for students to get into, all that to tape a lecture. Therefore, we (the faculty members of my department) have been advised to write a sentence about audio recording in the syllabus and explain the situation, including proper procedures to get consent and make recordings, the first time the class meets. I guess my message will be: if hearing my exact words is so important for you to understand the material, just come to office hours and I will go over the lecture again. Asking for help is not that complicated - and, in contrast with the high-tech method, it is perfectly legal.

Lehigh News

EvoLUtion seminar. I am a volunteer facilitator for the evoLUtion seminar again this year (see this old post of mine). All Lehigh freshmen and freshwomen are required to attend the four-session seminar, which aims to help students' transition into college and is organized by the Office of the First-Year Experience, or OFYE.

I first volunteered two years ago, when the program consisted of a single session and focused on a book all first-year students had to read during the summer before they entered Lehigh (in 2007, the Dalai-Lama's autobiography). The program expanded to four sessions last year; for this year, OFYE kept the same format - including the same book selection, Blink, by Malcolm Gladwell, about which I wrote last year: Part 1, Part 2 and Part 3 - but it added some interesting twists on the whole experience. For instance, freshmen now have to attend two campus events of their own choosing before the seminar ends. The idea is to encourage them to get out of their comfort zone and expand their horizons. Also, one of the seminar sessions will involve discussing short case studies, about some of the issues the students may encounter while at Lehigh. This will hopefully help them make better decisions if they are indeed faced with these issues in real life. I think OFYE did a great job designing the program.

At the training session, held this past Tuesday, I got a chance to meet the student orientation leader who will be assigned to my group. He is an accounting major. The group itself will consist of students from the colleges of engineering & applied science, arts & sciences and business & economics. One thing I love about the seminar is that it allows me to meet students from other colleges; this is the only opportunity I have to meet business or arts & sciences students, since I do not teach them. I think students enjoy the seminar because it is one more way for them to meet other freshmen and make friends early in the semester - and hopefully because it helps them adjust to college too.

First-year advising. The meeting of the academic advisors for the first-year engineering students was held today Wednesday. This is my fourth year advising freshmen, so I know the drill. I will advise thirteen students, like last year - I have found thirteen to be a good number, not too large and not too low. As an aside, I am often assigned first-year students who have expressed interest in the industrial engineering or information & systems engineering majors and, since I started advising freshmen in 2006 and teach a popular elective for seniors (I've got 55 students on my roster! We have to change rooms because the current one is not big enough to seat everybody, and I have no clue where the Registrar's Office will put us, because I teach at a time where most classrooms on campus are occupied), I'm going to have several students in my course whom I met on their first full day at Lehigh, back in 2006 when they were teenagers fresh out of high school. It is hard to believe three years have gone by already. I mentioned that to some of my more senior colleagues, who laughed and said this was nothing compared to the shock, which they have apparently experienced first-hand, of finding on their roster the children of people they taught back in the days when these people were undergraduates. That is when you realize time is passing by.

So freshmen move on campus tomorrow Thursday and the other students will arrive over the weekend; this will mark the end of the summer for me. Goodbye, easy parking! I'll miss you. See you next year.

Math Class for an Eighth Grader

Calla Cofield, one of the contributors of Cocktail Party Physics, has written a wonderful post about her eighth-grade math class (Math Class is Tough, August 15, 2009).

She describes how she failed basic algebra in junior high and was held back in math when she entered eighth grade. This greatly affected her sense of worth - she had taken pride in being smart - and her fourteen-year-old self felt extremely frustrated. But she was lucky to have a young, energetic and dedicated female math teacher, and she makes clear that her instructor being female played an important role in her getting better at math and beginning to enjoy it.

I particularly enjoyed reading her description of math, which matches my own philosophy: "Each problem is a mystery waiting to be solved. If you learn to speak the language and acquire the tools, you can break down the mystery, interview the witnesses and balance the equation. Quite frequently, the path to the solution is not straight forward, but the result of a series of creative moves. [...] I felt like maybe I could stick with a math problem if I thought the ending would be like solving a little mystery."

Cofield's post is also worth reading for her comments on gender differences, with amazing examples using Talking Barbie and Talking G.I. Joe. Make sure you read the paragraph in italics at the end, which is an excerpt of a 1993 article in the New York Times.

Wolfram Alpha: The New Search Engine

The July/August 2009 issue of Technology Review has a long article, entitled Search Me, about a new kind of search engine pioneered by Stephen Wolfram, the founder of Mathematica - a well-known "technical and graphical software for mathematicians, scientists and engineers". The search engine, which launched in May, is called Wolfram Alpha and has received significant attention in the mainstream press, including The Economist (The Search is On, May 14, 2009), and in engineering blogs such as Mike Trick's (Careful with Wolfram Alpha, July 31, 2009).

The article in The Economist describes Wolfram Alpha as "a search engine that computes answers instead of looking them up". Wolfram himself describes his brain child not as a search engine but as a "computational knowledge engine", best suited for queries that lend themselves to mathematical computations, such as counting the calories in a recipe. It also takes advantage of Wolfram's excellent graphics software.

As an example, if you type IBM and Apple into Google, you will return this: over thirty-nine million of pages where the names IBM and Apple appear and have been indexed by Google's bots as they crawled the web. But if you type IBM and Apple into Wolfram Alpha, you obtain that: a detailed analysis of IBM's and Apple's stock returns, complete with latest trades, fundamentals, recent returns, relative price history, performance comparisons, correlation matrix, and even six-month, one-year or two-year projections using random walk models.      

Wolfram's search engine relies on "curated data", i.e., data that a team of experts has "amassed, scanned, processed" to use in computations; this is in sharp contrast with the traditional approach, which collects as much information as possible and spits it out in the same exact form in query results. Technology Review states that only over the past year or so have search engines begun to evolve, for instance recognizing addresses, phone numbers or restaurants through the use of tags.  

More recently, Microsoft launched a new search engine, Bing, which is supposed to "organi[ze] its results in terms of relevant groups rather than a series of links" (, The Invention Machine, May 29, 2009). For instance, if you type Paris, you will get this - notice the headers "Paris Weather", "Paris Map" and "Images for Paris". But if you type Paris in Google, you will get that, which, dare I say, is just as well, with its maps and images at the top, and its "news results for Paris", "book  results for Paris" and "video results for Paris" lower in the page. According to, however, Bing is believed to have some semantic-technology capabilities, although it is not clear whether it is currently using them.

Besides mathematics and engineering, computational knowledge engines could be most useful for "specialist fields, such as medicine or law, where the terminology is limited". The journalist imagines a day where a chemist faced with expiring drug patents will find other uses for his equipment by typing a query into a semantic search engine. While this sounds a bit naive (if everyone can find business opportunities by asking a computer, the new opportunities will quickly disappear), the journalist also describes a fascinating demonstration of "deep content analysis", the next step in web searches ("far more impressive than Wolfram Alpha"), which will help machines "understand the complete and unambiguous meaning of human sentences".

The School Funding Formula

Mrs Dottie at Lehigh Valley Somebody has an excellent post on the funding situation of the Allentown School District ("ASD Faces Big Challenges", July 31, 2009).

First, this page from the US Census Bureau provides statistics for Allentown, Pa., that might be of interest to those of you who are not from the area and do not know the situation. Here are a few highlights:

  • Among people in Allentown aged 25 or higher in 2000, 72.7% were high school graduates, as opposed to 81.9% PA-wide; also, 15.4% had a Bachelor degree or higher vs 22.4% PA-wide.
  • 53.0% were homeowners vs 71.3% PA-wide and 18.5% were below the poverty level vs 11.0% PA-wide.
  • Among the people aged 5 or higher in 2000, 27.8% spoke a language other than English at home, vs 8.4% PA-wide, and 24.4% of all Allentown residents were of Hispanic or Latino origin, vs 3.2% PA-wide. 

Mrs Dottie writes about a study that a consulting firm in Denver performed for ASD, and highlights the challenges faced by the district, which attempts to provide quality education to Allentown children but struggles with a dwindling tax base, as taxpayers move to other school districts in the suburbs.

She also mentions a new school funding formula Governor Rendell recently introduced to provide more equitable funding and help poor students living in underfunded school districts receive a better education. Education is often these students' only option for a better future, which is something my family and I know firsthand; unfortunately, the fact that schools are funded by property taxes (and that in Allentown many multi-unit rentals are still taxed as the single-family homes they used to be) has long hurt such kids' prospects. The new funding scheme is an attempt to change that. Don't you love it when politicians start using mathematical formulas?

Here is how it works: the Costing-Out Report Formula determines an "adequacy target" for each school district, based on "the actual enrollment over a 5-year period, the number of low-income students and English language-learners, the district’s size and regional cost differences"; it is then compared to the district's actual funding, usually highlighting a gap. (The webpage does not say what happens if a school district is receiving more money than its adequacy target, but it does say that "[t]his year’s legislation also provides a 3% minimum increase to all school districts." Click here to read the costing-out study report.)

In addition, "[t]he state law sets a goal of phasing in each school district’s state share of adequacy funding -- $2.6 billion – over six years." The additional money will fund additional tutoring, smaller class sizes, and more training for teachers. It is not clear how the recession will affect those plans, but I hope that the most underfunded school districts will still get some of the much-needed money.

The webpage also states: "This year’s budget provides an additional $11.4 million to enroll 800 more children in Pennsylvania Pre-K Counts. [...] Reports from the first year show a 58% increase in the number of children meeting targets for early language and literacy skills." Quality early education plays a critical role in giving those kids a chance at a better life, which is why programs like First Book aim at putting age-appropriate books in the hands of children from low-income families. But ultimately the bulk of education happens in the schools, which is why I was surprised to read: "This year’s education budget [...] implements a real school funding formula in Pennsylvania for the first time since 1992." What took so long?

Statistics Are The Future

The August 5th issue of the New York Times has an article entitled: "For Today's Graduate, Just One Word: Statistics," about people with training in statistics being in ever-increasing demand or, in the words of Google's chief economist: "I keep saying that the sexy job in the next 10 years will be statisticians." (When I read the article, I immediately thought of a former student of mine and reader of this blog, who will soon head for Rutgers and its Master program in statistics after a very disappointing job search in the worst job market of the decade. It seems that Plan B - the Master in statistics - will open more doors down the road than Plan A. You know who you are, and this post is for you.)

Here are a few highlights:

  • “[T]he big problem is going to be the ability of humans to use, analyze and make sense of the data.” (quote by Erik Brynjolfsson, economist and director of M.I.T.'s Center for Digital Business.)
  • "The new breed of statisticians [...] use[s] powerful computers and sophisticated mathematical models to hunt for meaningful patterns and insights in vast troves of data." (I never tire of seeing the mainstream media mention mathematical models.)
  • The White House, and more specifically the director of the Office of Management and Budget, Peter Orszag (who, according to this Washington Post article, "proudly refers to himself as the administration's 'super-nerd' "), recognizes the importance of statisticians in producing "robust, unbiased data" to define and assess policies.
  • The article provides other signs of the growing interest in statistics, including the creation of a Business Analytics and Optimization Services at I.B.M. It also gives a great example of the number one rule of statistics, "correlation does not imply causation", through a story about the polio vaccine in the late 1940s.

Hopefully, the higher profile of statistics will spill over into related fields such as mine: operations research.

The Ones Who Have Grit, And The Ones Who Don't

The Boston Globe has a must-read article about grit, which "isn’t simply about the willingness to work hard" but is "about setting a specific long-term goal and doing whatever it takes until the goal has been reached." (The Truth About Grit, by Jonah Lehrer, August 2, 2009). While the idea that perseverance matters is nothing new, a researcher from the University of Pennsylvania named Angela Duckworth, and her collaborators, have developed tests to measure grit in a reliable manner, making it possible to determine its importance in predicting lifetime achievement.

"The hope among scientists is that a better understanding of grit will allow educators to teach the skill in schools and lead to a generation of grittier children." The United States Army has also provided funding for the study, in an attempt to better understand why 5% of West Point cadets drop out after the first summer, despite a rigorous selection process. Neither SAT scores nor physical fitness have been shown to have any predictive value; it turns out that grit does. Many people have long suspected that grit matters more than pure intelligence, but the lack of tests to measure grit, while "the IQ test [...] often took less than an hour", explains why intelligence "continued to dominate research on individual achievement." Duckworth also makes interesting comments on the role of grit in her friends' success, or lack thereof, after they all graduated from Harvard in the early 1990s.

The purpose of this research is not really to develop a test to measure grit, although that is a welcome milestone. Instead, Duckworth's long-term goal is to understand how grit can be learned, to help children (and adults) become more successful. That part of her research is still in its infancy, but Carol Dweck from Stanford University has found out that it is better to praise kids for their efforts rather than for their intelligence; otherwise kids get discouraged when they cannot accomplish a task. She refers to that as having a "growth mindset" rather than a "fixed mindset", which refers to "the belief that achievement results from abilities we are born with". The article also describes a very interesting study Dweck performed on New York City fifth-graders.

The article ends by bringing the focus back on Duckworth, who points out that, contrary to what Woody Allen once said, (most of) success is not just about showing up - "one must show up again and again and again."

Click here to participate in Duckworth's study.