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Posts from — March 2008

murky no more

DC recently suffered the inglorious closing of murky coffee, which had served what was by far the best coffee in town. First reported on in DCist, the Post later picked up the story, and owner Nick Cho has posted his version of the events on the murky coffee website. I did not visit murky as often as I would have liked: it was in a part of the city, near Eastern Market, that was awkward for me to reach. But whenever I was in the area, I would make a point of stopping in, usually for their amazing Classic Cappuccino. Fortunately, their branch in Arlington (even more awkward to get to) remains open, and I do hope Nick is able to follow through on his determination to open another DC store once his present mess is cleared up.

Nick, through his store and his through his efforts in the specialty coffee industry, has done wonders for the local coffee scene. I’ve been a coffee enthusiast since receiving a coffee grinder for my birthday while in high school. I soon picked up Kenneth Davids‘s Coffee: a Guide to Buying, Brewing, and Enjoying—my first in what is now a collection of many dozens of books about coffee—and Sacramento, fortunately, had a good number of respectable coffee shops.

Out of high school, I didn’t really keep pace with the specialty coffee industry. Chicago’s coffee scene was comparatively underdeveloped when I was at college, so although my collection of books grew, my coffee experience stalled (although a friend of mine and I did experiment with roasting our own coffee). The coffee shops in downtown Ithaca (but not on campus) were an improvement, but I didn’t have much opportunity to hang out in them. What I hadn’t realized, during this decade, was that a new movement in coffee was taking shape, calling itself the “third wave.” In a sense I kept missing it: Intellegentsia Coffee opened in Chicago just after I had left, and Gimme Coffee opened in Ithaca just as I was entering the intense dissertation-writing last year of my graduate school career.

Characteristic of third-wave coffee firms a never-ending pursuit of sensory quality, a bean-to-cup acknowledgement and appreciation of everyone in the coffee industry, and an ideal that everyone along that chain, from coffee farmer to barista, can make a comfortable living and have a successful career in their crafts. (Whether that last one is actually feasible remains to be seen.) Barista competition, travel “to origin,” direct-trade relationships, and critical cupping are part and parcel of the third wave. It seeks to move beyond the diversions that plagued the specialty coffee industry that I grew up with, such as flavored coffees and “sell-by” dates on coffee beans that are months after the roast date. It stands in marked contrast to the strategy adopted by Starbucks, which in order to keep up its relentless pace of expansion, replaced its La Marzocco espresso machines, which need a trained barista to operate, for push-button super-automatics, that any fool can use. That’s my take, anyway, on the third wave.

Nick brought third wave coffee to Washington. I met him once, when I took the espresso skills class he taught at his Arlington shop. Nevertheless, like many coffee aficionados, I feel as if I know him well, primarily because I listened to his podcast.1 The podcast, which Nick does with friend and Baltimore-area coffee shop owner Jay Caragay, is aimed at those working in the coffee industry. It’s heavy on insider gossip, often long and rambling, reliably entertaining, and occasionally brilliant. In part because of the podcast, Nick has (had?) been a rising star in the specialty coffee business, notably including a successful run for a seat on the board of directors of the Specialty Coffee Association of America.

Murky coffee was first closed by the DC government for failure to pay taxes, then evicted by the landlord. A controversy has erupted in online forums: is this, as Nick claims, the result of financial mismanagement spiraling out-of-control, or is murky trying to cheat on its taxes?

I’m convinced Nick is being honest. The picture one gets of him, from the podcasts, is of someone completely committed to quality coffee, with a purist streak that often puts his vision of great coffee ahead of business sense. He won’t, for example, sell you a straight espresso to go, and he wasn’t interested in selling the big-name soft drinks that the previous incarnation of a coffee shop had sold. And one also gets the sense that he’s prone to bouts of bad judgement: see podcasts 64 through 70 to see what I mean.

But please, don’t let those be your only sample of podcasts. Some of the most interesting ones:

53: An interview with Temple University historian Bryant Simon, who is working on a book about Starbucks.

27: Once you get past the first hour or so, which is mostly insider gossip, there’s a fascinating interview with Dean Cycon of Dean’s Beans, revealing why Fair Trade is a far more complicated subject than one might think.

26: Interview with Rob Stephen, then ascending president of the SCAA board of directors, on his vision for the SCAA and his experience working on Dunkin Donuts’ coffee program.

56: Interview with the directors and producers of the film Black Gold, which examines Ethiopian poverty in the context of coffee.

I suspect that the next podcast will go into tremendous detail about the shop closing; Nick has never shied away from discussing his personal difficulties. While his account of the events might leave a few things out, I really do think he’s being honest.

  1. The “explit” warning on the podcast is an understatement: several episodes become vulgar in a manner reminiscent of An Evening with Kevin Smith. []

March 25, 2008   1 Comment

Anyone for a meat-judging pool?

Via Ethicurean, a Wall Street Journal article about a shamefully under-appreciated and under-publicized competition… intercollegiate meat judging. I had no opportunity for this at my undergraduate institution, and even though my graduate institution has an Animal Science program, I think it focuses on dairy instead of meat. I do wonder if anyone runs meat-judging competition pools? Or if meat judging is ever televised?

March 22, 2008   No Comments

My March Madness

My graduate school was primarily a hockey school, although this year it has made the NCAA basketball Tournament for the first time in decades. In fact, my graduate institution plays my brother’s graduate institution in the first round (I don’t predict mine to win), and one of my grad school friends has his undergrad, graduate, and (present) faculty schools all in the tournament. (Take a look, though, at Chad Orzel’s bracket based on the strength of physics graduate programs: Cornell would win!)
While in grad school, I didn’t really follow the basketball team, and I don’t think I even went to a single game. But even though I don’t really, nor have I ever really followed college basketball, I will say that March Madness is the greatest sporting event in the world. Sixty-four games and they all matter.

My brother has, for a number of years, run the only March Madness pool that I participate in. Compared to the rest of my family at least (and sometimes his other friends as well) I tend to do rather well: I’ve never won but I have placed second twice. My general strategy is to pay as little attention to college basketball as possible during the regular season. This works: in our family, at least, there does seem to be an inverse correlation between the number of games watched and performance in the pool. Once, in graduate school, I tried to pick a bracket by flipping a coin, and it was absolutely dismal. I turn to two strategies, then, to fill out my brackets.


There are two strategies with statistical bracket-picking methods. The first is to try find the characteristics (such as average winning margin or number of times the coach has been to the tourney) that historically have led to success in tournaments, and to see which of the current teams best meet the characteristics of historically successful teams. Pete Tiernan is the highest-profile guru of this sort of work and he’s put together a set of phenomenological models that predict success at all levels of the tournament, from choosing a final four to picking the 6-11 upsets. Of course, I’m too cheap to actually pay the $20 to buy full access to his research, nor do I want to buy ESPN insider to read his in-depth articles there. And the big question here is whether the methods actually work: compared with all the brackets on ESPN’s tourney challenge, a model (he has about a dozen) that hits the high 90’s pecentiles one year very often hits the 30 percentiles the next. So it may like picking winning lotto numbers: the winners don’t win because of the strength of the model, but because if there are enough entrants, one will be the best.

The second statistical approach is to construct models of team skill, and either rank the teams or put them head-to-head. An amazing amount of free analysis is available from Ken Pomeroy and I’m sure there are other sources as well.

For bracket construction, it’s actually pretty boring to just use somebody else’s ranking list to fill out a bracket. I’ve put together one bracket that’s a sort of half-hearted attempt to use Tiernan’s guidelines (at least the ones you can read for free) combined with Pomeroy’s Pythag numbers. What I discovered is that, more often than not, the simple guidelines don’t give clear-cut results, so doing this thoroughly requires sifting through an awful lot of data, which itself requires a good deal of effort to find. And although I’m a numerically-minded person, my interest does wane after a while.


The method I like the most for bracket-picking is to see what all the sports pundits have to say. This year, at least, 5 writers for CNNSI and 5 writers for CBS Sports put their entire brackets up soon after Selection Sunday, and ESPN had 5 pundits with their Elite Eight picks. (CBS Sports has added two more brackets that I didn’t look at.) Sports pundits watch an awful lot of college basketball. To be a national-level sports pundit, you have to pay attention to all the conferences and a wide swath of teams. (This is where I think basketball enthusiasts stumble: they generally have their favorite teams and conferences upon which they focus their attention, and as a result overlook and underestimate the rest of the teams.)

What was interesting to me is the variation in pundit picks. All 5 of the CNNSI writers picked UCLA to win the tournament and none of the ESPN pundits did. All of the CNN pundits pick 13-seed Siena to upset Vanderbilt, while only 1 CBS pundit did. Four of five CNNSI pick 11th-seed St. Joseph’s to beat Oklahoma, while only one CBS did, while 3 CBS writers picked 11th-seeded Marquette to beat Kentucky, while only 1 CNNSI writer did. Out of all ten full brackets, there was only one prediction of a 14-over-3-seed upset: CBS writer Brian De Los Santos picked Georgia over Xavier.

In addition to sending them to my brother, I posted my brackets to the Washington Post Tourney Tracker: Search for thm_A_exp for the pundit-derived bracket, thm_C_stats for the statistics-derived bracket, and thm_B_pyth for the (boring to construct) bracket filled out strictly based on Pomeroy’s pythag statistic. I’m curious how each of these strategies fares in a wider pool of competition.

March 20, 2008   4 Comments

March Meeting observations

This year, I only went to the first three days of the March Meeting; extended trips are less feasible now with a baby at home. The trade show and posters are only Monday–Wednesday, and a fair number of attendees–particularly college faculty with classes to teach–stay for only a few days. So Thursday and Friday the conference is sort of a ghost town, but one thing I’ve heard from quite a few people this year is that it looks like several interesting sessions are scheduled for Thursday and Friday.

To read up on some of the physics presented at the March Meeting, a physics blogger’s account starts here. Physics journalists are blogging from the meeting here. Another attendee’s take is here. (I’ll update periodically if I find new blogged accounts.)
Photographing Talks
One phenomenon that’s becoming more common, and which is at least slightly disturbing, is for audience members to use digital cameras to photograph all the slides that a speaker presents. It’s obnoxious when the camera makes faux-shutter sounds, and it’s really obnoxious when the flash fires. When the flash is used, it’s also a sign that the photographer is an idiot, because the flash will make the image of the projected slide come out worse: physicists should be able to figure this out. If the photographs are unobtrusive, I haven’t quite figured out what the ethics of the situation are. I’d think if you really wanted someone’s viewgraphs, or data, you should just send them an email and ask: I’d share my data and graphs if someone asked for them.

I saw 39 talks this March Meeting, and only one used viewgraphs, and that was after the speaker attempted to use the computer but had some difficulty getting the computer to cooperate with the projector. The APS recommends that speakers have viewgraphs as backups; most don’t, but this speaker did, and the talk otherwise went off without a hitch. One out of 39 is 2.6%, which is a smaller fraction than last year (but not significantly so).

One piece of technology that number of speakers decided to do without was the (supplied) wireless microphone, which is a real shame. Perhaps the folks up front can hear the speaker fine, but there’s always a background rustling of papers and backpacks and schedule books, and people are talking outside the room, and if the doors are open this really filters in, and if the doors are closed then they keep opening and closing as people straggle in. It’s really hard to hear an un-miked speaker in the back of the room.

Because of the 39 parallel sessions, in which you wish you could be two or three places at once, people do lots of session-to-session shuffling. It’s always awkward to squeeze in to the open seats mid-session. The solution to this: more aisle seats! Instead of having two columns of seats, with an aisle down the middle and sometimes aisles down the sides, the APS should have the convention center arrange the seats to be at most 4 across, in 3–5 columns, so that everyone who wants an aisle seat–which is everyone who’s shuffling between sessions–could get one. It would cut down on the capacity a little, but although there are some overflowing sessions, there are plenty that are sparsely attended. To this end, the APS should try a little harder to predict the attendance at the sessions, and put the popular ones in the large rooms. I know this is hard, but isn’t this the sort of problem that physicists should be able to tackle?

New Orleans Convention Center
The March Meeting isn’t like a trade show, where you need lots of floor space, preferably contiguous, for all the vendors to set up their booths. Rather, we need lots and lots of meeting rooms. Convention centers, as a rule, have both, but some do the meeting rooms better than others. The shorter the distances between rooms, the better, because at the March Meeting it is common to try to shuffle between different rooms during a session. In New Orleans, there were two giant rooms on the first floor, and the rest were on the second floor. Most of these were along one long linear corridor, but a handful of rooms were in a parallel corridor on the other side of the center. To get between these corridors you went through an elevated walkway that overlooked the trade show floor. The convention center is along the Mississippi river. Between the center and the river are active railroad tracks. In the rooms on the river side, one could clearly hear the horns of the trains that used this track. I suppose this isn’t a problem inside a noisy trade show floor, but when you’re trying to listen to a talk, it makes you wonder why the architect didn’t specify more robust soundproofing on the walls that face the river.

The trade show:
Trade Show, March Meeting 2008
And the posters:
Posters, March Meeting 2008

The PAR 124 lives!
Perhaps the most exciting development, from my perspective, was the unveiling of the Signal Recovery 7124 Lock-In amplifier, so new it doesn’t appear on their website. Lock-in amplifiers are one of the most useful pieces of equipment in experimental physics research: They perform frequency selective signal detection and amplification, showing the amplitude and phase that appears on a signal in relation to a reference signal. They are tremendously valuable for processing noisy signals.

Years ago, a company called Princeton Applied Research (PAR) produced a truly amazing lock-in, the PAR 124. Built with all analog electronics, and mostly from discrete components, it was very sensitive, very quiet, and had been a staple of low-temperature research labs for decades. Contemporary lock-ins are, as a rule, digital, making use of Digital Signal Processing (DSP) to process the input signals, and do more with them than ever possible with analog electronics. But the digitization process itself is noisy, sending a sort of switching noise back up the input line to the experiment. This added noise and energy is very much unwanted in low-temperature experiments, so low-temperature labs kept PAR 124s around and sought them out from second-hand equipment dealers.

(I’ve used them in many of the mechanical oscillator projects I’ve worked on, but for a slightly different reason. Even when you use an external signal for the reference channel of the 124, the internal oscillator locks to your external reference and then this internal oscillator is used for signal processing. Because of the way this locking is accomplished, the 124 can be used to implement a phase-locked loop, by driving the mechanical oscillator with the reference signal output.)

Princeton Applied Research was bought by EG&G, who was then bought by Perkin-Elmer, then became Ametek, and who finally decided to call themselves Signal Recovery. And whenever they showed up at a trade show, such as at the March Meeting, low temperature physicists (including myself) would always ask if the PAR 124 would ever come back. “We’re working on it,” was always the answer.

And so they were. This March Meeting, they had on display the 7124 lock-in. It uses an all-analog front end, to which you connect your experimental signal. It’s connected by a 5-meter fiber optic cable to a digital DSP lock-in, so you can take advantage of all the advanced features of a DSP lock-in without the digitizing noise getting back to your sample. If I had a spare $15000 sitting around, I might buy one.

March 13, 2008   3 Comments

March Meeting 2008

I am now in New Orleans, for the 2008 American Physical Society March Meeting. This is a huge conference, lasting 5 days and attended by perhaps 7000 physicists. Most attendees give some sort of presentation, the bulk of which are contributed 10-minute talks; this is the first year that I’m attending without giving a presentation. This meeting only covers what is known as condensed matter physics–the folks doing particle, nuclear, and atomic physics have their own meetings.

Each day, there are three large time blocks of talks, beginning at 8am, 11:15am, and 2:30pm (although Friday only has the first two blocks). Blocks are assigned letters: A, B, and D for Monday, and continuing alphabetically until X and Y for Friday. Poster Sessions and special evening sessions also get their own letters; year-to-year, the assignment of the letters varies. Within each block, individual sessions are numbered, with numbers corresponding to the rooms used. If a room is not used one block, the number will be skipped: this year there are sessions A33 and A35 but no A34; there are, however, sessions P34 (on Wednesday) and V34 (Thursday), both in room 226 of the Convention Center.

Invited talks last 30 minutes, with 6 minutes for questions, contributed talks last 10 minutes with 2 minutes for questions. Talks within each session, of course, are grouped around a common topic. Each block runs for a full three hours and, for an entirely contributed session, can have as many as 15 talks. If you stayed for a full session and then went to the beginning of the next session, you’d get all of a 15 minute break between them.

To accommodate several thousand talks during the 14 3-hour blocks, the conference has, this year, as many as 39 parallel sessions running; last year there were as many as 43 parallel sessions. All total, this year, there are 518 sessions of talks. For each block, sessions 1 through 7 have 4 or 5 invited talks and no contributed talks; other sessions will have zero to two invited talks and as many as 15 contributed talks. All together, there are 729 invited talks this year in the regular sessions, and 5193 contributed talks.

Of course, some popular topics have more than 15 talks, and in this case, there can be multiple sessions with the same title, usually in the same room, with roman numerals appended. This year, in what must be some sort of record for such numbered sessions, there are 16 sessions on “Carbon Nanotubes and Related Materials.” Session 29 of every single block is devoted to this, and blocks B and D double up with Session 30. In these 16 sessions, there are 15 invited talks and 195 contributed talks.

The posters are treated as an afterthought. There’s no time set aside to look at posters; poster authors are instructed to be present during the third time block for each of the three poster sessions, which are, as a result, very lightly attended. Nevertheless, there are 1032 posters to be presented. Some physics bloggers have written about the poster-versus-talk question, and although people in other scientific fields can have a useful discussion about the relative merits of each, the culture of the March Meeting, which highly values the talk, seems unlikely to change.

Since the APS lets anyone who wishes to give a talk do so, any prestige associated from giving a talk is purely illusory (unless it’s necessary to convince the bureaucrats at one’s institution to let you go to the meeting in the first place). The prestige comes only from being sorted into a prestigious session, and getting a large audience. But, in the case with really popular topics, such as the aforementioned “Carbon Nanotubes and Related Materials” series, you still can’t see all of it, and even if you maximized your attendance, at 197 talks, you wouldn’t be able to see talks on any other topic, nor visit the trade show. And I’d imagine that a good number of those 197 talks wouldn’t actually be worth watching.

As far as I know, few other scientific organizations with conferences this big let anyone who wants to give a talk: more commonly, the only talks are invited presentations and the contributed sessions are posters, and there is a set time and some incentive (such as free beer) to attend the posters. I wouldn’t mind seeing the APS adopt this system. Certainly, one advantage of giving a talk is that it doesn’t have to be finished before you leave for the airport. But with 5299 talks, and the possibility to see at most 210 contributed or 70 invited talks, means there’s going to be stuff scheduled at the same time that you want to see. I’ve even known a session chair to be scheduled to give a talk in a different session as the one s/he is chairing! In the nanotubes case, it would probably be easier to scan through the 183 contributed papers as posters, looking at the titles and figures, and decide on the few you’d like to read in-depth, than to make it through 197 talks.

Posters help at the other end of the popularity scale as well, those people working in less popular fields. The attendance at talks can be quite varied, especially for those doing less trendy physics. I’ve been in sessions where the audience is about 6 people, usually four people waiting for their turn to talk and the other two labmates of the speaker. If there are only a handful of people interested in one particular topic, a poster session is more conducive to mutual discussion of each presentation than a handful of 10-minute talks in a sparsely attended session that’s only loosely bound together around a broad theme. And you can certainly fit more substance into a poster than into a 10-minute talk. I know there are several people (my graduate advisor, for example) who think that the March Meeting is so large, and that 10 minute talks are so insubstantial, that the March Meeting is not worth bothering with at all.

But for now, talks it is. Even for 10 minute talks, these days the overwhelming majority are given with laptops and Powerpoint. In 2005, it seemed, there was an equal balance between laptops and viewgraphs. In 2006, I definitely felt in the minority as a viewgraph-user, and I think for my session I was the first to use the overhead projector. Last year, I finally broke down and used a laptop (although apparently I had a problem with the display resolution). I kept tally: last year I saw 20 invited talks, 58 contributed talks, and only 3 used viewgraphs. Of course, with such a packed schedule there really can be no tolerance for slipping from the schedule, so those whose laptops refuse to behave are essentially out of luck. In fact, last year I did see a presenter use his entire 12 alloted minutes trying to re-boot his laptop and get the external display to work. (There is an AV ready room, in which presenters are encouraged to make sure their settings are correct.)

The posters are held in the same space as the trade show, where scientific equipment vendors have booths. The vendors (and their wares) tend to be the same from year to year. Perhaps the most interesting vendors are the scientific publishers, who have for sale all the new physics books of the year. I have a bookbuying habit, and usually pick up three or four new books at the March Meeting, but so far I’ve yet to actually read a book I’ve bought. The vendors hand out disappointingly little swag. And there is no conference swag: all you get when you register is a badge and the schedule book.

One soon realizes that the additional activities: receptions, special sessions, and the like, are also concurrently scheduled, and tend to stay at the same time slots from year to year. The only event I regularly attend is the alumni reunion for my graduate program, which is always held on Tuesday evening.

My strategy, for choosing what to see, is first to look at sessions in my research area. Then, I look for talks given by people I know personally, and also talks by people who I know to give interesting talks. Finally, I look through the lists of invited talks to see which have interesting titles. I might look over the abstracts for the talks or sessions that look interesting, but it’s hard to look through many abstracts beforehand.

To accommodate the large number of presentations, contributed abstracts are restricted to 1300 characters, about a paragraph. Until a few years ago, these were printed and bound and distributed to all conference attendees as two volumes, known as the Bulletin of the American Physical Society (BAPS), each of which resembled a phone book. To cut down on the bulk, they tried in recent years to simply give everyone CD-ROMs while having terminals with an electronic version of the BAPS are set up throughout the conference site. Now, we just get a bound volume with abstract titles; it resembles the phone book of a small city.

Of course now one can also download the program contents beforehand, and in order to facilitate my own planning, I wrote a few tcl scripts to parse the list of sessions and the list of invited talks and to make more readable forms of these. (If they didn’t require so much hand-tweaking each year, I’d post them–anyone who wants them, though, I’d be happy to share.) It’s in part from these scripts that I was able to get the numbers I quote here.

So what’s in it for me? Perhaps the most important thing I get out of the March Meeting is a chance to see what’s happening in a broad swath of contemporary condensed matter physics. The talks are as hit and miss as talks anywhere, and even if some of the same information could be gleaned by reading journals, I simply don’t have the time to read many journal articles outside my immediate field of interest. Of course, meetings are also good chances to catch up with grad school friends who are now dispersed at institutions across the country. But no matter what I end up doing, I find that the March Meeting always rejuvenates my enthusiasm for physics, and provides a motivational boost to continue my research back in the lab.

March 10, 2008   6 Comments