RIP Caltech Bookstore (Unknown--2009)

The economy has apparently claimed another victim.

I heard today from a friend that the Caltech bookstore will be defunct as of May 1st. I wonder what plans Caltech has for textbooks and ordinary supplies that it's especially convenient to buy on campus? My best guess is that simple supplies will be available at Caltech's convenience store, but I'm less clear about the textbooks. Maybe the nearby Borders will carry them?

On a more selfish note, how will people buy my book?

Anyway, the closing of Caltech's bookstore makes me a little sad.

De-Anonymizing Social Networks

Here is interesting but scary study on how to de-anonymize social network data. It's cool, powerful, and frightening.

Note additionally that there are multiple sides to the implications of such methods: Besides pure privacy issues, there are also the privacy issues that are conjoined with the increasing number of anonymized data sets that are being analyzed by scientists like me.

Big in Japan

Eri Yoshida, age 17 and Japan's first female professional baseball player, made her debut on Friday in the newly-formed Kansai Independent League (which is basically a minor league). A knuckleball pitcher who grew up wanting to emulate Tim Wakefield, she picked up a strikeout. As Rob Neyer points out, her small size is probably going to be her largest hurdle, but this is still awesome and I hope she gets very far.

Debriefing on the NSF 'Future of Network Science' workshop

I got back late last night from a military-run, NSF-sponsored workshop on the future of network science. The goal of the workshop was to brainstorm and try to develop a roadmap for developing 'network science' as a discipline in its own right.

Sadly, the workshop failed. ("I don't think your plan was very well thought-out... Master.") The organizers' method of doing this was ill-conceived, because they seem to think that this can be done in a physics framework and were hoping that there might be some sort of 'periodic table' of networks. I think that's too narrow-minded and tries to put a square peg in a round hole. Also, almost none of the leaders in the fields (from any of the various groups going on---in physics, CS, social science, engineering, etc.) were there. Hell, originally the workshop was going to conflict either with Sunbelt (so that none of the social scientists would be able to go) or the APS March Meeting (so that none of the physicists would be able to go). As it turns out, almost none went anyway. The organizers should have gotten around 10-15 leaders from these various fields, made sure they could come to the workshop, and then organized it around their schedule. (The 10-15 might have come from a list of, say, 30 stalwarts.) Then whoever among the rank and file (i.e., people like me) could make it then would come up to the numbers they wanted. (The size of the workshop was about right.) Also, based on the introductory comments and buzzwords, the organizers' knowledge seemed to be circa 2003.

We had lots of arguments about what a network is, and some people annoyingly insisted that it must have some sort of "flow", which would have the unfortunate side effect that things traditionally studied by bio networks people and many of the situations in the social sciences that are rather hard (that people still struggle with, as most of the research in practice deals with gross simplifications of these things) for which many of the important concepts were developed to get a handle on would a priori not be considered networks. So is the stuff for which a lot of the stuff was traditionally invented supposed to be outside of the scope of what we want to develop? That didn't seem to bother them, but I call bullshit on that one! This wasn't adopted, but some people kept bringing this up over and over again and really impeded progress. Personally, I think the suggestion of following the the Supreme Court's definition of defining pornography would have been a good way to go. :) Hence, one of my take-home messages of the workshop: "Network science is like pornography. We'll know it when we see it."

There were a few "awesome" comments during the workshop (both about the science and about other things):

"Monies will get exchanged between your government organization and our government organization."

"I can say some things that will make it sound like a network."

"If you're going to dress me up with Barabasi-type stuff, I'm going to walk out." (This was stated by a very annoying person. I was extremely tempted to pretend to believe that stuff just to see if he'd leave.)

"I know there are neurons. I know there's a lot of them." (says the medical scientist sarcastically)

"Some parts of some things have some properties of networks [I think "some of the time" then followed, though I forgot to type that here originally]." (This was particularly well-phrased, and this is pretty much exactly how I'd characterize things.)

Larry Leibovich really kicked butt as one of the voices of reason at the workshop.

"This led to an interesting and long discussion, which did not resolve anything." (This could be used to describe most of the discussions at the conference, though only some of the discussions were actually interesting.)

The random well-dressed guy was here (and actually I expected him to be here after seeing him show up as a military person in the 'How Kevin Bacon Cured Cancer' video).

Hmmm....

Hmmm... This post makes me wonder if the person who runs the blog Sad Guys on Trading Floors is a Techer (and a Lloydie)... Then again, maybe there is some other thing that that was originally referencing and I just need to catch up on a cultural tidbit...

Remixes of Terrorism Paranoia Signs

Courtesy Justin, here are the entries in BoingBoing's challenge to mock the UK's new signs encouraging people to be paranoid about terrorism. Some of these signs are pretty funny!

(The only sign missing is one that says that long-haired, freaky people need not apply...)

Logo of the Day

So I'm staying in the FDIC building... and in the lobby, every time I use the elevator, I pass by a sign celebrating their 75th anniversary that contains the motto "confidence and stability".

I don't think any additional comments are necessary, but here is a link where you can see for yourself.

Social Networking Sites (and related phenomena) for protests and reactions to them

CNN.com has an interest article about the upcoming G-20 protest and the roll of technology like Facebook and Twitter for organizing both protesting and reactions to them.

What happens in Arlington stays in Arlington (Virginia edition)

I just arrived in Arlington, VA for a 'Future of Network Science' workshop, in which part of the US military has used NSF funds to fly a bunch of us in with what I believe is the purpose of getting them up to speed on the state of the art in network science. The next couple of days should be filled with a bunch of interesting big-picture discussions. I am rooming with this guy, and I am wondering if we should do some sort of dueling blogging?

Comforting incident of the day: I just got into my seat in the plane when I see a guy in an LAX uniform with a big roll of duct tape. He headed to the back of the plane and came back several minutes later with a much smaller roll of duct tape...

One other thing: I am staying in the FDIC building.

Quote of the Day (it's all our fault)

Today's quote comes from Representative Maxine Waters [D-CA], who uttered the following comment about the financial crisis on the February 20th edition of Real Time with Bill Maher:

"But we're not going to change that until we put some people in jail. [Applause. Cheers.] We have got to take the schemers who have conspired by hiring these mathematicians and others to come up with these exotic products that rip people off and put them in homes that they could not afford ..."

Yeah, hiring mathematicians is a conspiracy. For thoughts on similar topics, see a blog entry by Arcane Gazebo.

Tip of the hat to the AMS Math in the Media webpage.

Now I better get back to working on my paper on community detection in currency exchange networks (with a focus on data from the current credit crisis)...

Grassroots CD Recording

Jill Sobule is officially awesome.

(If the name isn't familiar, two of her best-known songs are I Kissed Girl, which is one of the best songs of the 90s, and Bitter.)

Curt Schilling retires from baseball

Curt Schilling has announced his retirement from baseball. He did it with a post on his blog. I think Schilling belongs in the Hall of Fame, but he's an interesting borderline candidate.

Faces of Oxford

You can find my quick video interview for Faces of Oxford on this web page. When we did it, I thought it didn't come out well, but it's actually pretty decent. I said 'um' way too many times, but let me just use the usual excuse that I'm an American and don't know any better/can't be expected to use proper English/etc. (I have a similar track that starts with "I'm a mathematician.")

40 Inspirational Speeches in 2 Minutes

Here is a pretty cool YouTube video showing 40 inspirational speeches in 2 minutes. It doesn't have all of the ones I wanted to see (there's nothing about lollygagging, for instance), but it's pretty cool nonetheless.

(Tip of the hat to Rob Neyer.)

Best. Journal. Ever.

Courtesy Mariano Beguerisse Diaz, here is the best scientific journal ever.

It's called Rejecta Mathematica, and it only publishes papers that have been rejected by another journal. (Granted, one can already post the paper on the arXiv, but this is still bloody awesome!)

I think it's worth giving some of the content of their home page here. The aims of the journal are:

"Rejecta Mathematica is a new, open access, online journal that publishes only papers that have been rejected from peer-reviewed journals (or conferences with comparable review standards) in the mathematical sciences. We are currently seeking submissions for our inaugural issue."

Here is the first part of their 'about' section:

At Rejecta Mathematica, we believe that many previously rejected papers can nonetheless have a very real value to the academic community. This value may take many forms:

"mapping the blind alleys of science": papers containing negative results can warn others against futile directions;

"reinventing the wheel": papers accidentally rederiving a known result may contain new insight or ideas;

"squaring the circle": papers discovered to contain a serious technical flaw may nevertheless contain information or ideas of interest;

"applications of cold fusion": papers based on a controversial premise may contain ideas applicable in more traditional settings;

"misunderstood genius": other papers may simply have no natural home among existing journals.


Finally, the 'General Physics' section of the March Meeting will lead to some publications! Just don't get rejected from this journal... (I wonder if the authors of the web site buried the official revelation of the joke anywhere. I still can't find it and can only thank them for putting the time to create this web site. I approve!)

American Mathematical Society graduate student blog

I just read an American Mathematical Society (AMS) press release about an excellent idea: the AMS grad student blog.

I am not part of the intended audience, so I don't plan to add it to the blogroll. However, I wanted to highlight it because I think it's an excellent idea that will enhance communication among grad students at different institutions in a manner that nicely complements what already happens at conferences. I approve!

What happens in the Research Triangle stays in the Research triangle

I am now in the airport at San Diego, waiting for my red-eye flight to New Jersey, which will then go to Raleigh-Durham. I will be visiting my collaborator Peter Mucha at UNC, though I will also be stopping off at Duke on Tuesday (to give a math/physics seminar) and Wednesday (to give a social networks seminar, although that's more of an informal group meeting type deal). In fact, I will also be visiting a friend's lab at NC State on Saturday morning before she drops me off at the airport. I also have plans to see one friend from grad school who is now a postdoc at Duke as well as two friends from Caltech. Additionally, my collaborator JP Onnela will be flying down on Thursday for a bit of a synchronized visit and some additional work. It's definitely going to be both a fun and productive week.

Peter Mucha and I have numerous joint projects, though the one on which we'll probably spend the most time are our series of projects on Facebook networks. The American Physical Society press conference (held at the March Meeting) about our Facebook work is tomorrow morning (I think at 11am), and there will also be an APS press release (which I assume will come out tomorrow). They highlighted our student Mandi Traud's Tuesday talk at the conference, and she will be the one doing the press conference. We also have a poster in the GSNP Gallery at the meeting, and hopefully we'll have one of the winning entries. Stay tuned for more information about the media blitz...

Sunbelt Debriefing

Today was the last day of my first Sunbelt social networks conference.

There were a ton of statisticians (though they mostly consisted of ERGMers) a lot more CS people than I was expecting (though I figured there would be a decent number there), and a metric fuck ton of sociologists of all shapes, sizes, and stripes. Of the more than 500 people present, I was one of what was perhaps literally less than a handful of mathematicians + physicists. I have said this before and I will say it again: If the people from my side of the community want to maximize their impact on problems in the social sciences, then we need to publish in their journals, go to their conferences, and participate on their SOCnet mailing list. The number of individual collaborations is much larger than it used to be---this has really improved in the last couple of years---and I am not the only math/physics person who participates in SOCnet discussions, but we can't just be inbred and only publish in our own journals. It's not good enough.

I had a good time at the conference (though I think I would have had a lot more fun if I knew more than a couple of people), and several of the talks were excellent. Barabasi had to cancel, and I was really looking forward to the fireworks that were going to follow his talk. I got along quite well with the social scientists, and I felt accepted at the conference even though my background was so different from everybody else (even though some of the talks were quite quantitative). Carter Butts gave an excellent plenary talk, and Phil Bonacich gave the other non-cancelled plenary. (You can ask me offline about that talk.) I also found out that apparently Stan Wasserman---who seems to be addicted to Facebook, by the way, given how often he was logging in during talks---is buds with Vespignani and (to a lesser extent) Barabasi, with whom he apparently just likes to have fun arguing. One of the nice things about this conference was being able to match some names to faces (it was like 1999 again, when I went to the Snowbird dynamics conference for the first time, except that I am 10 years older), though of course I recognized only a small subset of the names of the well-known people. The only one of them I met was Barry Wellman, who is one of the main people from the origins of Sunbelt, and I got along quite well with him. One thing that I already pretty much knew but got confirmed was that the math/physics networks folks from Cornell-and-friends (the Strogatz-Newman-etc. crowd) are very well-respected in this community, whereas certain other prominent members of our community are not. (As many of you know, my origin in networks is exactly the Cornell-and-friends group.)

The conference was held in the Bahia Hotel on Mission Bay, so I got a chance to walk along the beach and to feel the breeze as I used my laptop or read. That's always good, though I did find that when I was walking along the beach I felt a bit lonely not having any friends around to walk with me. (I definitely felt out of place during those times because everyone on the beach was so different from me.)

Happy Pi Day!

Happy Pi Day! Don't forget to celebrate at 3:14 pm. I hope you already had an appropriate celebration at 3:14 am...

Highly Nonlinear Solitary Waves in Heterogeneous Periodic Granular Media

I have finally realized one of my life-long dreams: I now have a published paper that starts on page 666. (Who could ask for anything more?) And it's especially appropriate in this case, too, as the revisions for this particular paper were painful and entirely author-inflicted. Basically, the two referees (both of whom told us who they were during the process) asked only for trivial changes that took up about 0.25 % or less of the revision effort. We, on the other hand, had to deal with the fact that (among other things) the Caltech machine shop labeled "brass" as "bronze", which required us to rerun all of the numerical simulations with new (and correct!) parameter values. There were other issues as well, such as quadruple-checking the analytics and an extremely annoying factor of \sqrt{2}. So this paper really deserves to start on page 666, given all of the self-inflicted pain. It now has volume, issue, and page numbers, which means we're officially done, done, DONE with it! On to the next papers (which includes several follow-up papers to this article)!

Oh, and here are the title, authors, and abstract.

Title: Highly nonlinear solitary waves in heterogeneous periodic granular media

Authors: Mason A. Porter, Chiara Daraio, Ivan Szelengowicz, Eric B. Herbold, and P.G. Kevrekidis

Abstract: We use experiments, numerical simulations, and theoretical analysis to investigate the propagation of highly nonlinear solitary waves in periodic arrangements of dimer (two-mass) and trimer (three-mass) cell structures in one-dimensional granular lattices. To vary the composition of the fundamental periodic units in the granular chains, we utilize beads of different materials (stainless steel, brass, glass, nylon, polytetrafluoroethylene, and rubber). This selection allows us to tailor the response of the system based on the masses, Poisson ratios, and elastic moduli of the components. For example, we examine dimer configurations with two types of heavy particles, two types of light particles, and alternating light and heavy particles. Employing a model with Hertzian interactions between adjacent beads, we find good agreement between experiments and numerical simulations. We also find good agreement between these results and a theoretical analysis of the model in the long-wavelength regime that we derive for heterogeneous environments (dimer chains) and general bead interactions. Our analysis encompasses previously-studied examples as special cases and also provides key insights on the influence of heterogeneous lattices on the properties (width and propagation speed) of the nonlinear wave solutions of this system.

What happens at Sunbelt stays at Sunbelt

I am writing this entry from San Diego, where I am attending my first Sunbelt social networks conference. Based on early estimations, I seem to be one of about 5 math/physics types in a conference with over 500 social scientists. (Let the festivities begin!) All of tomorrow's talks are workshops, and I didn't pay to participate in any of them, so my plans are just to mill around, get some work done, and soak up the atmosphere.

One of the things I have told some of you before is that if people studying network science are going to influence the social scientists, we need to not just go to our venues (the March Meeting, NetSci, etc.) but also to theirs. The social scientists who know me seem to be pretty happy with the work I am doing, so I think I'm doing reasonably well in trying to establish some local connections. This has become much more common over the last couple of years, and hopefully there will continue to be more of it.

I'll try to confirm the rumor that social scientists dress much better at their conferences than mathematicians and physicists do at theirs. Stay tuned.

Correlation Versus Causation

Courtesy Aaron Clauset, here is a a big win by the comic strip XKCD about correlation versus causation.

I approve!

What happens in the United States stays in the United States

I flew from Heathrow to LA yesterday and had a layover in the Twin Cities. As has become a tradition, I added a bit of a small incident with Customs Security to my resume. (Will somebody explain to me why so many of these people insist of being sarcastic without any provocation?) Part of it is that those people just can't handle the fact that I would choose to have a job somewhere outside of the US. (I am asked how long I've been gone, and I have to then explain that I live in the UK, which always leads to several subsequent questions.) When I say I am a professor, I am always asked what kind. (Note that yesterday I actually tried saying "mathematics professor" for that answer, and there was a brief bit of confusion when the guy didn't notice that I had said mathematics. I thought for a bit that he actually wanted me to say what kind of math I studied. I was like "Do you really want me to describe that?") This guy sarcastically asked "What do you profess?" I told him I was a math professor, though my heart screamed to give any one of a number of sarcastic responses at that point (unlike Roxette, I did not listen to my heart on that particular occasion), I just answered. His response was to ask me what the square root of 237 was, and he seemed a bit perturbed that I then paused to figure it out in my head. How else was I supposed to react? Anyway, he seemed convinced because of that and then let me through. All of this, of course, was after he told me he didn't want me puking on him (the whole motion sickness deal).

I'm on Caltech's campus right now, and I saw someone walk by with a t-shirt that said "Don't be a d^3s/dt^3" (I'm using latex notation here) on the back. (Yes, people at Caltech wear shirts like this! So do I, obviously...) I feel like I should get this, but I'm not. I was thinking of 's' as arclength, but I'm not sure. Does anybody have any ideas here? I must be missing something obvious...

RIP Milton Rowen (age 91)

Dr. Rowen was the principal of Hawthorne School (my elementary school) during my first few years there. (I am listing him only by age because I don't know whether he was born in 1917 or 1918.) The main thing I remember about him is that we were all scared shitless of him because he would come into the cafeteria where we were having lunch, and if he saw something he didn't like he would scream at all of us. I think a couple of times he even screamed right in the face of some young kid. (Unsurprisingly, he had a military background.) He's treated rather kindly in the brief obituary in Beverly Hills Weekly, but for me this was a guy to fear, not to respect. I speak as a tree rather than as a forest, but at the time, I was quite pleased when he stepped down.

Quote of the Day

"I'm so happy I could strangle a mountain ox."

That was the response I got to an e-mail to a student accepting her to do a Ph.D. with me. My response: "I take it this is a 'yes'? ;)" Though of course I can't take the above as an official yes, though I think it's reasonable for me to expect to get that answer. I guess there is something to be said after all for delivering such news rather than it being done by departmental staff. (Granted, I have to deliver bad news more often than good news.)

Happy late Square Root Day!

Somehow, I needed to read this article after the fact to realize that yesterday was Square Root Day!

Please send me a reminder in 2016...

Chance Meetings

I was taking the train today for the first time in a couple of months so that I could go to Stoke-on-Trent to take a cab and head over to Keele University for a talk. The train was running late---shock!---so I ended up on a differently-configured itinerary that was leaving 30 minutes later. I was trying to find two consecutive empty seats so that I could have some space and I noticed while passing by lots of situations without such empty seats that one person seemed to look vaguely like someone I know. I didn't think much about it, though, because she has a postdoc at Brown and it was not reason it would be her. Except that it was, as she had flown in this morning for a job interview at Warwick. (Some of my readers may know who this, but I am withholding the name from a public web page for obvious reasons.) That was pretty cool! This is among my least-expected random encounters ever. (I have occasionally run into friends unexpectedly at random airports before---e.g., once in Dallas when I was making a connection---but at least they were in the right country!)

Anyway, this is my cool story for today.

Manny is staying in LA.

This was inevitable: Manny Ramirez will remain a Dodger in 2009. Thankfully, we mostly resisted the urge to bid against ourselves (which is a Scott Boras specialty).

Tales from the arXiv: It's Not Easy Being Green edition

Here is a new abstract from the arXiv:

arXiv:0903.0110 (*cross-listing*)
Date: Sat, 28 Feb 2009 21:20:21 GMT (1127kb,D)

Title: Kermit's What-Happens-Next-Machine Reloaded
Authors: Ursula Schroeter
Categories: physics.ed-ph physics.class-ph physics.pop-ph
Comments: tricky, but feasible. 13 pages, 11 figures, + 7 pages attachments
with FORTRAN program
\\
If Kermit's What-Happens-Next-Machine had functioned, you would not have seen
much, because it would have gone too quickly. In this article it is shown that
putting up and solving the equations of motion of a seemingly simple mechanical
apparatus presents a challenging problem. The simulation can, however, be quite
instructive and also entertaining.
\\ ( http://arxiv.org/abs/0903.0110 , 1127kb)