29 December 2006

I'm part of a movement!

Who knew that even by neglecting my blog, I could be joining a 200-million strong online movement?
The firm has said that 200 million people have already stopped writing their blogs.


"A lot of people have been in and out of this thing," Mr. Plummer said.

"Everyone thinks they have something to say, until they're put on stage and asked to say it."

However, just to show I haven't totally slid into apathy, here is a letter I just wrote to the NYT about what's missing from their recent Ford hagiography.
To the editor,

Much of your coverage of the Ford presidency was nostalgic and moving, but I was disappointed that you neglected to mention Indonesia's 1975 invasion of East Timor, which used mostly American weaponry, killed an estimated 200,000 out of 700,000 people and led to a 25-year occupation. The day before the invasion, Ford and Henry Kissinger were on a state visit to Indonesia, where Indonesian president Haji Mohammad Suharto asked for "understanding if we deem it necessary to take rapid or drastic action." Ford responded with "We will understand and will not press you on the issue," while Kissinger asked only that the invasion wait until Kissinger and Ford had returned to the U.S.

Aram Harrow

I should point out that I didn't know of Ford's involvement here until I learned it from Jon Schwarz and Dennis Perrin, although my first letter to the The Tech (which was actually published!) was inspired by my realization that even in 1998 the Clinton administration was illegally arming and training the Indonesian military.

So now will I join Bernard, Carla, Julia, Michael, Dan, Fafblog and all of my other fellow no-longer-bloggers? Or will I turn to page 123 of some book and flesh out all of those drafts on book reviews, freedom of information, math problems, anti-nationalist mockery and women's underwear? All I know is that I'm not going to promise anything.

01 October 2006

if you live in the U.K.

Watch this show tonight on BBC2 at 8pm. In the U.S., you'll have to wait another month or so.

It's called Battle of the Geeks, and the premise is that in each show two crack teams of inventors/engineers (a.k.a. "geeks") compete to perform a different task in a different part of the world. This show takes place in the second largest canyon in the world: the Fish River Canyon in Namibia. Each team was given an egg

and their task was to get it as close as possible to a target on the other side of the canyon, about a kilometer away with a vertical drop of 200m. Without breaking it. The target in the photo is the red-and-purple X on the left. It's 10 meters across, which should help give you a sense of scale.

You can find a much more detailed description, with better photos, from my friend Jeff's account of being on the show.

25 September 2006

unglorious problems in quantum information

Along the lines of Scott's 10 annoying problems in quantum information (now happily only 8), I have a handful related to universal gate families.
  1. Let V be an imprimitive gate in U(d2), meaning that it cannot be written as a product of two gates in U(d). We know that V and V-1, together with U(d) x U(d) (i.e. all local gates), can exactly generate all of U(d2) [quant-ph/0108062]. But if we don't have access to V-1 then we only know how to approximate all of U(d2). Without the subgroup structure, general tools like quant-ph/0209113 can't be used. This is clearly an absurd situation, but show me the simple proof that V and U(d)xU(d) are exactly universal (which remarkably, I could actually make use of in a proof) and I'll agree that I'm being dumb.
  2. Does the Solovay-Kitaev theorem still hold if we aren't given inverses? Obviously, yes, but can we prove it? Even without giving an efficient construction of the approximating sequence?
  3. Some univeral gate families (e.g. (1 +- 2 i \sigma_j)/sqrt(5) where j ranges over x,y,z) have the property that a sequence of length O(log 1/eps) can approximate any gate to within accuracy eps. This matches the Omega(log 1/eps) bound from counting epsilon-balls. Does the O(log 1/eps) upper bound hold for all universal gate families? Solovay-Kitaev only guarantees O(log^(3+o(1)) 1/eps) sequence length, but it probably makes the sequences longer than it has to by requiring that everything be poly-time.
This last one is actually something that real mathematicians have considered, but not solved. But the first two I'm almost too embarassed to ask them! I mean, come on, people: we can pull this together.

A different sort of unglorious problem is the kind that someone else has solved, but couldn't be bothered to write up. Watch this space later for Shor's construction of higher-accuracy embezzling states and Kitaev's O(t) quantum communication simulation of e^{-itZZ}. Or more realistically you could corner me or Debbie at a conference some time and ask for an explanation.

automatic 401k enrollment

[This post starts slow, but the interesting point is at the end.] 401K's are a great deal (employer matching funds, tax-free interest), and make sense for pretty much everyone who's not completely desperate for cash. But people don't take them very often (40% of low-income workers, 50% of workers in their 20's). And it's probably not (just) because people don't want to save; it's more that they're paralyzed by inertia and having too many choices. This is evidenced by the fact that when people are enrolled by default in 401k's, most people (like 80%) stay enrolled and continue making whatever the default contribution is. (The sheep-like trust here reminds of this English guy I met who doesn't wash vegetables because "if they had toxic chemicals on them, the store wouldn't be selling them to us.")

Recently a new bill made it easier for employers to automatically enroll their employees in 401k's mostly by shielding them from lawsuits if the investments don't perform well. According to marketplace

[Harvard retirement scholar Brigitte Mandrian] expects more employers will migrate to automatic 401k enrollment. But slowly, cuz it's pricey. More employee savings means more matching funds from their bosses.
This is the weird part. Employers are doing something which costs them money, and, though it helps their employees, it only helps the employees who didn't really care about the benefit they're getting. The people who are excited about getting 401k's are probably the ones who'll enroll even if it's not the default. Could it be that the companies really do care about the welfare of their employees? Explaining Safelite Auto Glass's decision to automatically sign up their employees to invest 2% of their pay (matched by the company), Brenda Downing says:
We had a significant number of associates not saving at all. We were concerned they weren't going to be OK at the time they retired.
Is corporate benevolence really the only answer here? This is making my head hurt.

15 September 2006

no seriously, don't profile

Sarcasm may have obscured the point of the last post. Profiling makes even less sense against organized terrorists than against criminals. Why? The age/ethnic mix of terrorists that we see now is in part a reaction to the security that they'll face. If young men are always searched then female suicide bombers will be recruited, and the defenses will be worse off than if they screened passengers randomly. This isn't just a game theory exercise:
On April 17 1986, a young woman presented herself at Heathrow's gate 23 for that morning's El Al flight to Tel Aviv. She had cleared the airport's own security check-in procedures, but to El Al's security staff something didn't appear right. A search of her hand luggage revealed 1½ ounces of Semtex and a detonator, hidden in a calculator.

The young woman was Anne Murphy, a white, Catholic girl from Dublin. The explosives had been planted by her boyfriend, Nezar Hindawi, a terrorist with links to the Syrian government.

Of course, I'm starting to give the impression that we should worry about terrorism, when in fact doing so has surpassed the war on drugs as one of the worst acts of collective hysteria since McCarthyism. For example, think of dying prematurely as an enormous waste of time (like reading blogs! but worse.) The average adult has about 300,000 hours of waking life to expect, and a 1 in 13,000,000 chance of dying on the average U.S. domestic flight (this was true in 1990-1999 entirely from accidents, and in 2000-present almost entirely from 9/11, as there's been only one fatal accident during that time. Your chance of dying on a developing world flight is 1 in 1.5 million, regardless of carrier. These and other fascinating facts found here). If you're risk-neutral, avoiding this risk should be worth two minutes of your time. By this argument, two minutes is also a good baseline for the amount of time that airport security should be willing to waste per passenger. The last point is the crudest part of the argument and shouldn't be stretched too far, since it's based on the risks we currently see, which might change in the extreme case of airports completely eliminating screening. Needless to say, I think we're far from that point. (Incidentally, google for probability terrorism dying to see how a little math knowledge can be an upsetting thing.)

The time vs. death comparison seems a generally useful one because it avoids all the problems in comparing lives with money. Another place it's obviously relevant is in speeding. The probability of dying while driving is supposedly proportional to the fourth power of your speed. In the U.S., drivers die at a rate of about 15 per billion miles and are seriously injured at about 10 times that rate. If we assume the fourth-power law and that everyone is driving 65mph (assume a spherical cow...), then increasing speed by 1mph will save 0.84 seconds/mile and increase the chance of being killed/mile by about 9.2 x 10-10. Multiply by 300,000 hours and you get just about one second, which is pretty close to the amount of time saved. To account for injury, one method is to examine the number of disability-adjusted life years (DALY's) lost. In 2002, 1.18 million died in traffic accidents and 38.4 DALY's were lost, which comes to about 33 DALY's/death. This means my "50 years/death" was an overestimate and increasing 1mph actually costs closer to 0.65 "disability-adjusted life seconds"/mile. Even if we assume there's another car involved half the time, this is close to a tie, meaning that 65mph is close to optimal. On the other hand, this still hasn't included property damage (which ranges from 1% of GNP in developing countries to a stunning 2% in rich countries), higher gas consumption and the fact that speeding tickets waste time too. So I think this means that

  1. we shouldn't speed Moderate speeding is a little dangerous, but not unreasonably so.
  2. Applying the 300,000 hours argument to airline security can't be totally absurd since it leads to different conclusions in different contexts.
  3. I should stop wasting so much time writing silly blog posts.
p.s. I look forward to Ilya's theory of driver safety profiling in the comments!

Update: Thanks to Aaron in the comments for pointing out mistakes in my driving calculations (now corrected); I had represented driving as 10 times more dangerous than it actually is.

14 September 2006

terrorist profiling

People get all worked up about this idea, but think about the benefits:
  • People spend on average less time in line.
  • Terrorists get caught more often.
Of course some people will get unnecessarily searched, but that's happening already! And just think of the absurdity of the status quo, when airport screeners waste their time searching uneducated young men and aren't left with enough time to catch the older, more educated, threat.
Suicide bombers who are older — in their late 20’s and early 30’s — and better educated are less likely to be caught on their missions and are more likely to kill large numbers of people at bigger, more difficult targets than younger and more poorly educated bombers.

... Whereas typical bombers were younger than 21 and about 18 percent of them had at least some college education, the average age of the most successful bombers was almost 26 and 60 percent of them were college educated.

Experience and education also affect the chances of being caught. Every additional year of age reduces the chance by 12 percent. Having more than a high school education cuts the chance by more than half.

There are many examples where young or uneducated terrorists made stupid mistakes that foiled them. Professor Benmelech recounts the case last April of a teenager from Nablus apprehended by Israeli soldiers before carrying out his bombing because he was wearing an overcoat on a 95-degree day. Mr. Reid, the failed shoe bomber, had only a high school degree. Would an older terrorist with more education have tried to light a match on his shoe (as Mr. Reid did) in plain view of the flight attendant and other passengers who proceeded to thwart his plan? Would a better-educated terrorist have been more discreet? We will never know.

The research suggests, however, that there may be a reason that the average age of the 9/11 hijackers (at least the ones for whom we have a birth date) was close to 26 and that the supposed leader, Mohammed Atta, was 33 with a graduate degree.

The solution is simple. Passports could be linked to electronic education records and every year of education could increase the expected length of screening by an extra 12%. Liberals will whine about unfair treatment, but winning the war on terror is about being effective, not pleasing a few politically-influential constituencies.

30 July 2006

Our Troops

I finally met one.

On a recent flight from San Diego to Newark I sat next to a Marine around my age who had done one tour in Iraq towards the start of the war, and now was about to start a second one. Even though over a million U.S. troops have been to Iraq or Afghanistan in the last five years, this is the first time I've talked to one.

And he wasn't happy about the idea of going back. I didn't feel like grilling him, but he talked only about how things had gotten more unpredictable and dangerous since the start of the war: "You never know who's going to want to kill you. Someone might come to a checkpoint five times and be all friendly each time, but then the next time will try to blow you up."

In particular, I didn't feel like asking him about the overall futility of the U.S. presence there, but elsewhere in the Middle East he was sharply critical. We were talking about evacuations of foreign nationals from Lebanon and he talked with disgust about how the U.S. military later billed the people it rescued for the costs of the helicopter flights. This bothered him not because of the principles of action-movie heroism, but for reasons I'd associate more with Chomsky: "Really the [U.S.] government should be responsible for the costs [of the rescues] since they're the ones who created the situation by arming Israel, and giving the green light without which this invasion wouldn't have happened." I mentioned our recent expedited delivery of precision-guided bombs to Israel and he responded with something like "well, duh."

What made the conversation sad was how he already seemed to want to block out the upcoming Iraq episode from his life. He talked about how he had liked living in California, and said many times that Iraq was "not going to be fun." When I responded to his talk about unpredictability by saying "yeah, I read recently that now Sunnis are the ones who are more supportive of the U.S. presence since they're afraid of getting dominated by the Shi'a. It's pretty crazy how quickly the situation shifts over there," (Billmon discusses this topic with more bite.) he only said "I haven't been briefed about that yet. They'll do that soon, I guess. [He was headed to Indianapolis for two weeks before shipping out.] All I know is that you can never tell who's on your side."

I liked this guy. We had a (to me) hilarious exchange about California. He was from North Carolina, but said CA was surprisingly nice and that "all those things they said about it were totally not true."

me: Um, yeah, I like CA too. But what things do people say about it?

him: You know, about the people there.

me: Wondering how to translate 'effete' into non-ironic. You mean that they're elitist or something?

him: vague words to the effect of Well, that they're not good people then exact words that I'm not going to forget that they're practically like foreigners over there. But actually I found almost everyone to be really nice and I'm gonna miss living there.

me: Sorely tempted to remark that while I had earlier said I liked living in England, it is true that they're not just "practically like" foreigners over there. Instead I told my favorite California chill story, which I include here for completeness. I was riding a bus in SF when the driver got out, went into a fast-food store, came out with a drink, saw someone he knew, gave them a hug and chatted briefly before getting back in the bus. And the people riding the bus didn't lynch him on the spot!

I might be extrapolating here, but I liked how he was open-minded enough to question the (anti-CA and pro-war) prejudices he had been raised with. I hope that in Iraq he doesn't get killed or end up killing anyone else.

technically he should be the one to report this bug

A recent mozilla bug-tracker post opens with the line: This privacy flaw has caused my fiancé and I to break-up after having dated for 5 years.

The free-ranging mixture of the personal and technical (e.g. "Steps to reproduce bug: 1. Create 2 unique Windows XP user accounts. 2. Log into one and open Firefox. ... 9. Break up with fiancé.") gets only more amazing in the responses, ranging from the "let's see how the personal problems complicate the technical issue":

I don't know if you still have access to the computer you and your ex-fiancé shared, but it sounds like Firefox was sharing a profile between the two Windows XP user accounts. How is that possible -- were both users administrators or something? Were bookmarks separate?
to the sisterly
Honey, I would think you would be the LAST person to be bothered by this [bug, presumably]. Not only did was he using your computer to be unfaithful, he wasn't smart enough to cover his tracks, and you got to know about it BEFORE buying the goods. If you're really THAT upset about finding out, take him back and pretend you never knew, or hold it over his head and use it to keep him in line.
to the creepy
Maybe this was a huge wake-up call after 5 years... maybe he's not the guy you thought he was... maybe its been 5 years of deception... Or, maybe it was just minor 'reveal' and not evidence of deep, serious transgression...just a 'white lie' where he was covering up some fantasy needs...and the 'white lie' need only be a bump in a long, long road and you can see if you can turn it into a growing experience..a call for a whole new level of openness in your relationship..

If the relationship is otherwise a complete wash, what is there to lose? Get it all out on the table.. Tell him he might as well say what he REALLY wants in his life.. what would his 'fantasy perfect male existence' be? Get it stated, honestly and openly for once.. And then see whats what..

Best of luck..

to the philosophical:
Really it's not that big of a deal that firefox saves the list of not saved passowrds. Browers are supposed to do this kind of thing. Anyway it would be the cheating boyfriend's job to run a cleaner to clean the history and cache.
Also included are an unrelated anti-Windows rant, a response consisting entirely of a Jesus quote, and much much more.

04 April 2006

Is it too much to ask that...?

cous-cous be steamed 2-3 times instead of just dumping boiling water on it and fluffing it with a fork? I mean, really, people.
When I feel like laughing or crying I google recipes for couscous. The vast majority are junk. ... Of course I'm delighted that couscous is becoming increasingly popular in different parts of the world and it's none of my business to tell someone what they can or cannot do with couscous.

If you want to eat delicious couscous it must be steamed at least 2-3 times. There really is no other way. ... If you are chef who has published such a recipe I really hope you don't prepare it like that in your restaurant. ...

Okay, I've been googling more. It looks like every Tom, Dick and Harry site has a couscous recipe! Maghrebis and couscous fans UNITE, email them, tell them how couscous should be prepared!!!!

From an Algerian cooking blog that's making me hungry, linked from an article about Bague de Kenza (Since I was buying for my whole department, I instead went to a cheaper place in the 18th called El Andalousia; also tasty, but of course I can't compare.)

But my point isn't about cous-cous, it's about what motivates people to begin an impassioned rant. Recently on the BBC I heard part of a Distinguished Lecture by this gentleman:

This year's Reith Lecturer is the eminent conductor and pianist Daniel Barenboim, a leading cultural figure of our time. His remarkable career spans more than five decades. He has worked with all the world's great orchestras and now holds the posts of Music Director of the Chicago Symphony Orchestra and General Music Director of the Deutsche Staatsoper in Berlin.

He is also co-founder, with the late Edward Said, of the West-Eastern Divan Orchestra which brings together young Arab and Israeli musicians. "Music", argues Barenboim, "lies at the heart of what it is to be human".

Should be good, eh? And the theme of the lecture?
In this lecture recorded in front of an audience at the Symphony Center in Chicago, Barenboim tries to rescue the neglected sense - the ear - and launches his own campaign against muzak.
He descibes his experience in writing to American Standard (you know, the company that makes toilets) to complain about their choice of Mozart's Requiem as the soundtrack for one of their toilet commercials. Apparently confusing him with a more common kind of letter-writing nutjob, they sent back a form letter saying that they weren't aware of the religious significance of the music, but were responding to complaints in the next round of commercials by replacing it with one of the highlights from something by Wagner which "music experts had assured them had no religious significance whatsoever."

I laugh, but I get far more comments about the exponential letter than anything else on this blog.

26 February 2006

illegal aliens or self-leveraging entrepreneurs?

What does it mean to cross into another country, stay illegally either avoiding border guards in the first place or overstaying a tourist visa, find a series of short-term jobs that pay cash, all while staying out of sight of the government whenever possible? According to a popular NYT article , it means "having international experience under your belt" (about which "employers are enthusiastic"), demonstrating that you are "inquisitive, flexible and adaptive---valuable skills in today's workplace," and, (contrary to what the cynics say), "it's not a money-making move," but rather "It puts you in a position to leverage yourself."

At least for some people. Meanwhile, Congress is starting to consider a guest worker bill for immigrant labor from south of the border. What are some of the key provisions for the budding Mexican entrepreneurs?

Applicants would be sponsored by employers — though they would be allowed to switch employers during their time here — and would undergo background checks and medical screening.


The draft bill would also authorize millions of illegal immigrants who arrived in this country before Jan. 4, 2004 to remain here indefinitely, along with their spouses and children, as long as they registered with the Department of Homeland Security, paid back taxes and remained law-abiding and employed, among other conditions.

Elsewhere in the paper, the Times editorial page argues that in "a nation that insists on paying as little as possible for goods and services, and as long as it remains impractical to send lawns, motel beds and dirty dishes overseas," we need a more humane and reasonable immigration policy. It says that "Congressional action is long overdue," and closes with
Laws that make it a crime to help illegal immigrants find work will make outlaws out of local leaders whose only crime is to want to live in orderly, humane communities.

Setting up a hiring site with bare-bones amenities like benches and bathrooms is not an indulgence of lawlessness. It is a common-sense tactic to help prevent the exploitation of workers, to rein in unscrupulous contractors and to impose some order on the chaos. It is smarter and more humane than the cruelty of harassing legislation that hopes, somehow, to make all those men and women disappear.

In other words, taking a practical approach to migrant labor as a solution to our demand for low wage, unregulated, seasonal work isn't about coddling illegal immigrants; it's the only realistic and humane solution to prevent them turning into a social problem for us and our communities.

(Not that I don't agree with the policy position of the NYT in both cases: I think living abroad as soon as you're able to be independent of your parents is a good idea, and most of the immigration reforms proposed right now would help people. It's just the terms of the debate, and the implicit assumptions that shape them, that are fucked up. This sentence lightly revised 9 July 2008.)

On a vaguely related note, I have at least one more data point supporting this essay: a white Parisian woman I talked to who distinguished the Maghrebians (French citizens living in Paris of N. African descent) from the French. As in, les Maghrebins in this neighborhood of Paris do X, but les Français living there do Y. I still love it here! And in my very limited experience, I still see a decent amount of social mixing between natives and immigrants. But I had to point this out.

12 February 2006

Senegalese recipes

general principles: Almost everything is in big pots on high heat. Use lots of mustard and garlic, and add the mustard early so it infuses the onions.

fish balls

Mash up pepper, garlic, parsley, Maggi (basically bouillon cubes, but the Senegalese version has MSG too), tuna and a little flour---in that order---in either a food processor (Western version) or a giant mortar and pestle (Senegalese version). Form into little balls (it helps to rub your hands with oil for this) and deep fry in batches, turning only once or twice through the whole process. Remove from oil with a slotted spoon when each side is done.

Next, dice onions and fry in the leftover oil (preferably peanut oil) until light brown, then mix in a good deal of mustard (something like smooth Dijon) and keep cooking for a few minutes. Meanwhile you should be boiling some vegetables (like eggplant, cabbage and carrot) in a sepearate pot. Once the onions have absorbed the mustard, add the vegetables and just enough of the water to cover them (using water that's been boiled means tap water is fine). Add salt, more Maggi and a little vinegar. Boil till everything is soft enough, then add the fish balls, and cook on low a little more. Serve with (short-grain) rice.

Fermented lemon juice: Add salt to lemon juice and let it sit in the sun for awhile. Here I've only tasted the final result.

Yassa chicken

Again, food process peppercorns, then garlic. Then combine with (optionally fermented) lemon juice, Maggi, lots of mustard, and a little water and boil chicken in this. Once the chicken is nearly cooked, remove it from the marinade and grill it on both sides. Meanwhile boil vegetables separately (carrots, eggplant, "African eggplant", whatever). Meanwhile, slice onions and fry in a ton a of (peanut) oil until brown. Then add mustard, cook for a little while, add the chicken marinade, the vegetables and, if necessary, some water. When the chicken has been grilled on both sides, add that too, but cook on low, and only long enough for the chicken to absorb some of the sauce. Optionally separate chicken, vegetables and sauce for serving. Serve with rice.


Mix flour, salt and yeast, then add just enough water until it's nice and doughy. Knead well, brush with a little oil, and leave covered in a warm place; then repeat. Prepare tuna as for fish balls above, but cook in oil for awhile, then mix tomato concentrate with water and cook in this mixture until most of the water is gone. Then let it cool. The tuna should be breaking into smaller and smaller pieces, but by the end it may be necessary to further shred it. Grab a small ball of dough and flattened on an oiled surface, put a little bit of tuna in the middle, fold over, and press the edges shut with a fork. Deep fry in batches until golden brown, turning once or maybe twice. Sometimes served with a tomato-onion sauce, but instead this recipe combines the tomato with the tuna.

These really are tasty, but I'm not sure my sketchy description is good evidence for this. A shout-out goes to our femme de menage Yaye, for among other things, cooking all this, and then having the patience to teach me. At some point, Shefali will enter a recipe for Mafe into the comments and I'll update the post.

09 February 2006

Her voice is full of money

"She's got an indiscreet voice," I remarked. "It's full of---"

I hesitated.

"Her voice is full of money," he said suddenly.

That was it. I had never understood it before. It was full of money---that was the inexhaustible charm that rose and fell in it, the jingle of it, the cymbals' song of it... High up in a white palace the king's daughter, the golden girl...

From The Great Gatsby.

This same idea (substitutability of desire) can also be illustrated using more scientific language. The link is via Tyler Cowen, who also argues that in general, fiction and science have more in common than one would think.

Update: After reading that last paper, I can say that you get everything you need out of it from the abstract, or even just spending awhile thinking about the title and its implications. To me the overlap can be seen by looking at the questions: how do you argue that your claims are true, that they are interesting and/or that they generalize? In both cases a blend of precision and ambiguity is necessary, a specific insight together with a claim to reflect a larger truth, etc... The differences between a novel and a scientific paper then come from different definitions of truth, interestingness, and so on. We can see this by looking at how these concepts have changed over time: for example, many early English novels were meant to scare girls away from sex, so they were much more didactic and specific than, say, a Salman Rushdie novel. The "interest" of these novels is clearly related to their educational/social value; in some ways not so far from a modern social science paper, but with a more condescending relation between author and reader. Similarly the concepts of truth and universality change over time and across fields. But these are just the sort of things I was hoping were explored in Cowen's paper! I'm not actually going to go through them myself...