In today’s Wall Street Journal, Carl Bialik writes about "statistical time travel" performed by number-crunching researchers.

"In recent years," writes Bialik, "statisticians have created time machines to answer a wide range of historical hypotheticals, from how today’s Supreme Court would have voted on Roe v. Wade to what sort of scientific papers Einstein might write today."

One of the researchers highlighted in the article is Princeton computer scientist David Blei, who has done a computational analysis of more than a hundred years’ worth of Science magazine.

This is how Bialik describes Blei’s research:

"His system identifies topics from scratch and assigns topic scores — say, 80% neuroscience and 20% philosophy, or 40% biology and 60% chemistry. Any papers that have the same topic scores could then be grouped together, even if they are decades apart and keywords or concepts didn’t yet exist. (Think of quarks or H1N1.)

"Here the critical bridge — the necessary overlap to relate past decades to the present — were keywords that were associated with others before they faded… Such techniques connected an 1880 paper on orangutan brains with a 1976 paper on monkey brains.

"That technique helps dig up research that was ahead of its time. For instance, these very time machines, including Dr. Blei’s, make use of so-called Bayesian statistics, which were developed decades before there was sufficient computing power to use them fully."

You can hear Blei talk about his work in this 2007 Google Tech Talk. Blei’s recent research includes papers on "finding latent sources in recorded music," "a computational approach to style in American poetry," and "augmenting social networks with text" — this last paper being coauthored with former student Jonathan Chang, now at Facebook, who in a recent blog post describes various visualizations he created of’s twitter traffic.


The Silicon Valley Leadership Group honored NetApp Chairman and Princeton Engineering alumnus Dan Warmenhoven last week for lifetime achievement and contributions to the community.

"Dan Warmenhoven is not only a highly talented and creative technology leader, he is one of Silicon Valley’s finest community leaders," said Carl Guardino, president and CEO of the Leadership Group. "Along with his wife Charmaine, their contributions to the arts, the culture and the needy in Silicon Valley set the standard that each of us should try to emulate."

The group also honored Stanford President John Hennessy. Among the thousand or so Silicon Valley glitterati at the event were California Governor Arnold Schwarzenegger and senators Dianne Feinstein, and John McCain.

Both Dan and Charmaine Warmenhoven earned their undergraduate degrees from Princeton — his in electrical engineering, hers in psychology. Read more in the Silicon Valley Business Journal and the San Jose Mercury News.


The Princeton and Rutgers chapters of Engineers Without Borders are holding a benefit banquet on Nov. 12. The reception starts at 6 p.m., with dinner and a silent auction to follow.

EWB does amazing work, so if you have an extra fifty bucks to spare (the minimum donation that will get you into the benefit), you would be hard-pressed to find a more worthy cause.

Check out EWB’s water irrigation project in Ethiopia in the video above. Or read here about their Ghana library drive. EWB is asking that you RSVP by Nov. 1 to If you misplaced your official invite, you can download a copy here.

Video by Taofik Kolade and Anthony Soroka


Thumbnail image for John Dabiri_Popular Science.png

The Princeton Alumni Weekly this week has a fascinating profile of bioengineer John Dabiri, who graduated from Princeton Engineering in 2001.

Last year Popular Science magazine named Dabiri one of its "Brilliant 10," dubbing him the "jellyfish engineer." By studying the way that jellyfish propel themselves through water, Dabiri draws inspiration for a range of engineering challenges, from designing energy-efficient underwater vehicles to developing a new method for early diagnosis of heart disease.

Dabiri, who majored in mechanical and aerospace engineering at Princeton, is now a researcher at CalTech and has also been featured recently by Time, The Epoch Times, Environmental Research, and Ecoworldly.

Photo courtesy John B. Carnett of Popular Science


The blogosphere is reporting on a new paper coming out of Princeton that applies computer science theory to the field of financial derivatives. The Daily Kos summarizes the paper’s fairly astounding findings thusly:

"Scientists have proved that it is possible to create complex financial bundles (you know – bundles of mortgages that have ‘a few lemons’ that are supposed to average out and make the whole bundle great investment) that hide bad assets in such a way that no computer or human can detect the bad assets."

Worse, the blog continues, "Even after a buyer loses their shirt on the investment, it is impossible for the buyer to prove that they were sold junk, which makes it impossible to regulate."

The paper is Computational Complexity and Information Asymmetry in Financial Products by Sanjeev Arora, Boaz Barak, Markus Brunnermeier, and Rong Ge. Arora and Barak are with Princeton’s Center for Computational Intractability and coauthors of Computational Complexity: A Modern Approach, published earlier this year by Cambridge University Press.

Read the full blog commentary on the Daily Kos, Boingboing, Freedom to Tinker, Gödel’s Lost Letter and In Theory.


C Programming Language book covers.png

Computerworld recently profiled Princeton’s legendary Brian Kernighan, who in 1978 wrote the now-classic C Programming Language  with C’s creator, Dennis Ritchie. You can follow the slashdot conversation about the Kernighan profile here.

The book has sold millions of copies and been translated into a couple dozen languages, including Hebrew, Finnish, and Albanian. The screen grab above, from Kernighan’s website, shows the covers of different translations. 

Kernighan — who earned his doctorate from Princeton in 1969 — teaches the very popular Computers in Our World course, which The New York Times‘s Steve Lohr wrote about a few years back in a piece called "To the Liberal Arts, He Adds Computer Science". Kernighan is also a regular columnist for the Daily Princetonian and recently last year wrote an essay for an IEEE publication delineating what every educated person should know about computers

By the way, Kernighan helped inspire the name for this blog.



Technology Review this month reports on new types of conductive inks being produced by Vorbeck Materials Corp. that can be used to print RFID antennas and electrical contacts for flexible displays. 

The inks are made from graphene,  the most stable form of carbon on Earth, using a technology developed by Princeton’s Ilhan Aksay. Vorbeck, which just received $5.1 million in financing from private-investment firm Stoneham Partners,  was started by Princeton Engineering graduate John Lettow, who did his senior thesis research under Aksay. Read the full TR piece here.

Image courtesy Hannes Schnieppe


This week the BBC posted a guest editorial by Princeton’s Fred Dryer, who outlines different ways the aviation industry can become more energy-efficient.

"Bio-derived fuels must be fully compatible with petroleum fuels, particularly for aircraft applications, because of the international nature of the aviation industry," writes Dryer, who is professor of mechanical and aerospace engineering.

In June, Dryer gave a talk on his combustion research as part of a larger workshop on energy and the environment sponsored by Princeton’s Andlinger Center. You can watch the full workshop here. Award-winning science journalist Patrick Regan of NJN-News also covered the workshop and produced another piece on combustion science at Princeton.

Regan produced those pieces just before leaving NJN to explore new frontiers in Munich, Germany. His exemplary science reporting will be sorely missed. Regan’s coverage of Princeton Engineering included pieces on new lasersriver biodiversitynanojet printing, a robotics competition, and Princeton’s Science Olympiad.


Chicago airport_people mover.jpg

The current issue of New Scientist magazine reports on two new mathematical models created by Princeton Engineering postdoctoral researcher Manoj Srinivasan demonstrating that airport "people movers" — those human conveyor belts that propel passengers from point A to B — tend to slow down travelers.

"Srinivasan’s models predict that when a person steps onto a moving walkway, they slow their foot speed by about half the speed of the walkway," reports MacGregor Campbell in the New Scientist. "This suggests that our desires to conserve energy and to resolve the conflict between visual cues and leg muscle signals — your eyes tell you that you are going faster than your legs are taking you — slow us down so that our total speed is only slightly greater than it would have been on regular ground."

When the airport is congested, as it often is, this means that travelers would get wherever they are going faster if they just walked.

The Daily Telegraph also reports on the research.

Above photo of Chicago airport by base10, Flickr/Creative Commons


New Jersey Governor Jon Corzine and other prominent politicians were on hand yesterday to christen Princeton Power Systems‘ new office at the historic Sarnoff corporate park.  

Andrew Kitchenman of  NJ Biz quotes Corzine as saying that Princeton Power — started by Princeton Engineering alumni — is an “important company that fits into our clean energy master plan.” Princeton Power board member Greg Olsen — who is also entrepreneur in residence at Princeton’s School of Engineering — described the company as a “New Jersey success story.”

A couple of years ago, Mechanical Engineering magazine ran a terrific in-depth article on Princeton Power’s startup odyssey.  Find the full NJ Biz story on yesterday’s ribbon-cutting ceremony here.