Icosian Reflections

…a tendency to systematize and a keen sense

that we live in a broken world.

IN  WHICH Ross Rheingans-Yoo—a sometime quantitative trader, economist, expat, EA, artist, educator, and game developer—writes on topics of int­erest.

John Nash, 1928-2015

CNN | Mathematician John Nash, wife killed in car crash

John Forbes Nash Jr., the Princeton University mathematician whose life inspired the film A Beautiful Mind, and his wife died in a car crash Saturday, according to New Jersey State Police.

Well, okay, somehow the fact that his life inspired a Hollywood film made it into the obit before the fact that he won the 1994 Nobel Prize in Economics. (Note: "Nash called the film an 'artistic' interpretation based on his life of how mental illness could evolve -- one that did not 'describe accurately' the nature of his delusions or treatment.") But in actuality, it's enormously difficult to describe the impact that this man had on the field of Game Theory, which now underlies much of economics, politics, and has even been applied to describe the strategy of penalty shootouts in soccer (where it closely predicts the strategies that top players actually use).

And if you're anything like me, you'll find his 1950 dissertation a refreshing respite from page after page of obituary:

Non-Cooperative Games (typewriter facsimile)

Introduction

Von Neumann and Morgenstern have developed a very fruitful theory of two-person zero-sum games in their book Theory of Games and Economic Behavior. This book also contains a theory of n-person games of a type which we would call cooperative. This theory is based on an analysis of the interrelationships of the various coalitions which can be formed by the players of the game.

Our theory, in contradistinction, is based on the absence of coalitions in that it is assumed that each participant acts independently, without collaboration or communication with any of the others.

The notion of an equilibrium

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A Meditation on π

note: This is not a volley in the \(\pi-\tau\) debate, of which Vi Hart is undisputed monarch -- and right, as well -- as far as I'm concerned.


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A few number-theoretic \(\pi\) facts:

  • \(\pi\) is provably transcendental, thus also irrational.
  • \(\pi\) is suspected, but not known, to be normal, a generalization of transcendence.
  • \(\pi\), provably, has Liouville-Roth constant (or irrationality coefficient) no greater than \(7.6063\), and is suspected to have constant no greater than \(2.5\). (As a consequence of its irrationality, its L-R constant is \(\geq2\).)

Note, though, that each of these things is also true of literally 100% of numbers. And before you scoff at my use of the figurative 'literally', no no -- measure-theoretically, the non-(normal, transcendental, irrational, irrationality-coefficient-less-than-8) numbers make up exactly, mathematically 0% of the number line.

For the record: irrational algebraics like \(\sqrt2\) are also nonterminating and nonrepeating, and it's not clear what features of the stringwise-local decimal expansion (which seems to be the only thing \(\pi\) enthusiasts focus on, rather than the much-more-informative continued fraction representation...) distinguish transcendentals from irrational algebraics -- and yet \(\sqrt2\) seems to mystify no one, despite also plausibly encoding all possible variations of Hamlet, going on forever, holding all the universe's secrets, &c.

For more, the ever-wonderful Vi Hart:

Right so. Scott Aaronson has a recently-published essay titled "Why isn’t it more mysterious?", in response to the prompt "Q: Is there something mysterious about mathematics?":

Granted, not all mathematical mysteries have the character of "rigorously proving what common sense would predict." In 1978, John McKay noticed that the number 196,883 showed up in two completely

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April 17 Links: The Ecuadorian Tourism Agency, and Other Air Travel Pranks

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Ecuador, attempting to prove that it's indistinguishable from Costa Rica, tricks a tour group thinking they've gone to Costa Rica into believing that they were going to Costa Rica when in fact, they were taken to a part of Ecuador that was, apparently, indistinguishable from Costa Rica.

I'm really not kidding:

As Ecuador residents arrived, not in Costa Rica but another Ecuador airport, Tena, where they were given fake stamps in their passports as they went through a staged passport control. No attention to detail was spared as huge posters were placed over the welcome billboards at the airport. Adverts depicting Imperial beer and 'Esencial Costa Rica,' Costa Rica's national brand, were displayed in the airport to throw the group off the scent.

Even fictitious immigration documents and car licence plates were created to make the group think they were in Golfito, a port town in Costa Rica. On top of all that organisers used mobile phone and GPS blockers to keep passengers from using technology to discover the hoax. (...)

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In more serious airline news, the Congressional Research Service, a policy-analysis agency within the Library of Congress, released a 20-page report titled Terrorist Databases and the No Fly List: Procedural Due Process and Hurdles to Litigation. Footnote 41 (of 201!) reads:

Prior to 9/11, aviation security was handled by the Federal Aviation Administration (FAA). The FAA ordered air carriers not to board certain individuals who were deemed a threat to aviation safety. On 9/11, this "no fly" list contained 12 names.

Somehow, I guess I assumed that there were more than twelve people on the no-fly before 2001. But then again, in hindsight,

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False Flag Flyers

content warning: defense of satire of certain critiques of racism; critique of censorship of satire of certain critiques of racism; critique of certain critiques of racism

content note: As should go without saying, zero defense of racism intended.

socioepistemic status: white male ally


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The Harvard Crimson | Posters Parodying Advocacy Magazine Prompt Controversy

Posters that parodied a new campus arts and advocacy magazine that focuses on issues of race and diversity prompted criticism from students and administrators in Pforzheimer House this past weekend.

...

Official Renegade posters in Pfoho had white backgrounds with black text containing phrases about race and diversity, such as "because Mather owned slaves"... The apparent parody posters, however, were black with white text and included the messages "because all straight white men are racist" and "because anyone that disagrees with me is racist." The posters included the url of the magazine’s website and its launch date. (...)

note: After reading a few articles in Renegade, one of my friends needed to take a break so badly they left campus for an afternoon to be anywhere but here. I expect that the magazine has useful things to say, but here's an anecdatum suggesting they don't know how to pull their punches; take care of yourselves accordingly.

False-flag tactics in social advocacy are selfish, since they (1) erode a public expectation of frankness in favor of monotonous cynicism, and (2) prime people's minds with the most-polarizing views of conversational participants, instead of framing them in ways that induce exchange of ideas. The right reason to critique the satirists here is for their anti-conversational tactics -- not their demonstrated anti-anti-racism -- since we shouldn't be okay with the same tactics

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April 10 Links: The Once and Future Friday Tradition

Back after more than two months, the Friday linkwrap!

(Does anyone else get as excited for these as I do? No, right?)

So, I've been pretty delinquent about these, but at least I've had the decency to keep stashing things I found worth reading at Reading Feed, with backlogs at Reading Feed (March 2015) and Reading Feed (February 2015).

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WSJ | China to Start Keeping a List of Badly Behaved Tourists sounded pretty scary -- until I read the article and realized that the measures are directed at Chinese citizens abroad, not visitors to China. And then it all sorta made sense, conditioned on China being, 'yknow, China.

Said Chinese president Xi Jinping:

Don't throw water bottles everywhere, don't destroy people's coral reefs and eat fewer instant noodles and more local seafood. (...)

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On the topic of environmentalism, I'm on the record opining that pressuring the Harvard Management Corporation to divest from fossil fuels is a red herring, but that doesn't mean that digging up all of the of the known deposits of fossil fuels and burning them would be exactly as horrible as you'd expect: (all numbers Fahrenheit)

The next set of fossil fuels in line is referred to as resources, rather than reserves. The difference is that they are recoverable with today’s technology, but not at current prices. There is 3.1 degrees’ worth of warming if the oil and natural gas in this category are utilized, which would lead to a total increase in global temperatures of 7.6 degrees.

This warming does not even consider our coal resources. A middle-of-the-road estimate of the coal that qualifies as resources indicates that its use would lead

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I'm in the HPR!

I'm in the Harvard Political Review today, with a guest piece responding to Eric Posner's anti-effective-altruism opinion in Slate:

Posner...is convinced that this tendency toward scrupulosity is enough of an issue that we should abandon the concept of effectiveness in altruism entirely. His critique, though, is not a new one—several effective altruists are also concerned about scrupulosity, and many of them have shared stories from their own lives about balancing giving effectively against more personal cares. For me, these stories are important because they demonstrate that caring about effective opportunities to do good is not mutually exclusive with making the world better in other ways you choose. (...)

Much-deserved thank-yous go to Advik Shreekumar, Ben Kuhn, and Leah Libresco for helping with edits. Meanwhile, here's the original version with footnotes (the HPR doesn't do footnotes).

Man, writing for real publications is so stressful. Word limits, even if they're only suggestions, suck.


A few things that didn't make it into the HPR version (besides those glorious, glorious footnotes):

Scott Alexander defends a definition of "doing effective good" that's keyed to a 10% donation, rather than a [maximum]% one:

If you want to feel anxiety and self-loathing for not giving 100% of your income, minus living expenses, to charity, then no one can stop you.

I, on the other hand, would prefer to call that "not being perfect". I would prefer to say that if you feel like you will live in anxiety and self-loathing until you have given a certain amount of money to charity, you should make that certain amount ten percent.

Why ten percent?

It's ten percent because that is the standard decreed

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Lower Tuitions at Stanford


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Stanford's in the news today for: Stanford just made tuition free for families earning less than $125,000 per year. The news is usually accompanied by pictures of smiling students and balloons:

A smiling student and some balloons.

For example.

...and it usually takes the article in question a few paragraphs to get around to noting that:

The announcement is an expansion of Stanford's old financial aid policy, which previously applied to students from families making less than $100,000 per year. (...)

...which raises the question: Just how many students at Stanford come from families with incomes greater than $100k and less than $125k? ...and just how desperately did those families need to have their tuition costs reduced from \(\leq\)$13.5k[1] to $5k[2]?

(EDIT | A bird in my ear mentions that $100k/yr puts you in the 80%tile of American families, which seems at least approximately-correct.)


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About a year ago, Ken Griffin donated $125 million in support of Harvard's financial aid program, funding 539 full scholarships to Harvard. Kim Soffen, writing in the Harvard Political Review, wrote:

An important first note is that the recipients of this new pool of money will not be the poorest students at Harvard; even before this donation, Harvard already guaranteed full scholarships to any family making under $65,000 per year, and that families making up to $150,000 would not have to pay more than ten percent of their income. Consequently, these additional scholarships would be going towards students from families who are already safely

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