Control

Really great piece at Vox on how you can over-control tests to the point where the thing you're trying to detect is controlled away in a misleading way. 

Statistical controls are great! Except when they're not.

The problem with controls is that it's often hard to tell the difference between a variable that's obscuring the thing you're studying and a variable that is the thing you're studying. 

An example is research around the gender wage gap, which tries to control for so many things that it ends up controlling for the thing it's trying to measure. As my colleague Matt Yglesias wrote:

The commonly cited statistic that American women suffer from a 23 percent wage gap through which they make just 77 cents for every dollar a man earns is much too simplistic. On the other hand, the frequently heard conservative counterargument that we should subject this raw wage gap to a massive list of statistical controls until it nearly vanishes is an enormous oversimplification in the opposite direction. After all, for many purposes gender is itself a standard demographic control to add to studies — and when you control for gender the wage gap disappears entirely!

"The question to ask about the various statistical controls that can be applied to shrink the gender gap is what are they actually telling us," he continued. "The answer, I think, is that it's telling how the wage gap works."

It's a difficult chicken and egg problem, very relevant to studies of racism in police enforcement.

Imagine applying these controls to society itself. We still have race, but people of all races have the same amount of money, and they live in the same kinds of neighborhoods, and they do the same kinds of drugs, and they even drive the same kinds of cars. That society would be a lot less racist. But part of the reason we're so far from that society is racism. Discrimination perpetuates itself.

In some ways, what's amazing about many of these studies is that they show a racial effect even after controlling for so much of racism's work. They show that racism exists even in our control society — the one with equality of income, and education, and neighborhood, and car choices. The one where we've wiped out most every difference but pigment. The one where we've left ourselves no excuses for our prejudice. It is remarkable how much discrimination can survive.

Read through Harold Pollack's emailed thoughts at the bottom of the piece.

The barbell in barbells

We may be seeing a pronounced barbell distribution in the profitability of gyms:

One way to see it is to look at the two gym brands commonly cited as the fastest-growing in America: CrossFit and Planet Fitness. Both are expanding like crazy. CrossFit has gone from having 13 affiliate gyms in 2005 to 10,000 today. And Planet Fitness has more than tripled in size over the past five years.

But aside from their bang-up growth rates, the two could not be more different. The former is expensive and intense, appealing to competitive individuals ready to commit thousands of dollars and many hours to working out. I go to a CrossFit gym a few blocks from my apartment. It costs $160 a month, often more than I spend on groceries. The latter is perhaps most famous for giving out free pizza — a fact it embraces and publicizes, no less. Its monthly fees are normally around what a movie ticket costs.

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It is the middle that is growing more slowly, with some chains struggling to demonstrate their value to consumers — your Bally Total Fitness, now all but defunct, or Curves. It is the gyms with considerable but not intolerable monthly fees and decent amenities, but no sheen of luxury or promise of extraordinary results.

Or perhaps this is some variant of the smiling curve, with high end gyms offering the value add of the company of the other well-heeled folks embracing a high cost public signal of their willingness to spend on their physical fitness (itself a signal of many other things, including self-discipline, health, and matching level of vanity).

Quadratic voting

What is quadratic voting (QV)? Essentially, voters would make a one-time purchase of votes from a clearinghouse at a price equal to the square of the number of votes purchased. It is a proposed approach towards limiting the power of the majority or wealthy interests.

According to this research paper:

If individuals take the chance of a marginal vote being pivotal as given, like a market price, QV is the unique pricing rule that is always efficient. In an independent private values environment, any type-symmetric Bayes-Nash equilibrium converges towards this efficient limiting outcome as the population grows large, with inefficiency decaying as 1/N.

Eric Posner is positive.

Quadratic voting is the most important idea for law and public policy that has emerged from economics in (at least) the last ten years.

Quadratic voting is a procedure that a group of people can use to jointly choose a collective good for themselves. Each person can buy votes for or against a proposal by paying into a fund the square of the number of votes that he or she buys. The money is then returned to voters on a per capita basis. Weyl and Lalley prove that the collective decision rapidly approximates efficiency as the number of voters increases. By contrast, no extant voting procedure is efficient. Majority rule based on one-person-one-vote notoriously results in tyranny of the majority–a large number of people who care only a little about an outcome prevail over a minority that cares passionately, resulting in a reduction of aggregate welfare.

Tyler Cowen has some great thoughts.

My reservation about this and other voting schemes (such as demand revelation mechanisms) is that our notions of formal efficiency are too narrow to make good judgments about political processes through social choice theory.  The actual goal is not to take current preferences and translate them into the the right outcomes in some Coasean or Arrovian sense.  Rather the goal is to encourage better and more reasonable preferences and also to shape a durable consensus for future belief in the polity.

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I would gladly have gay marriage legal throughout the United States.  But overall, like David Hume, I am more fearful of the intense preferences of minorities than not.  I do not wish to encourage such preferences, all things considered.  If minority groups know they have the possibility of buying up votes as a path to power, paying the quadratic price along the way, we are sending intense preference groups a message that they have a new way forward.  In the longer run I fear that will fray democracy by strengthening the hand of such groups, and boosting their recruiting and fundraising.  Was there any chance the authors would use the anti-abortion movement as their opening example?

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By elevating persuasion over trading in politics (at some margins, at least), we encourage centrist and majoritarian groups.  We encourage groups which think they can persuade others to accept their points of view.  This may not work well in every society but it does seem to work well in many.  It may require some sense of persuadibility, rather than all voting being based on ethnic politics, as it would have been in say a democratic Singapore in the early years of that country.

I had never heard of quadratic voting. It's a fascinating idea, essentially putting some sort of effective cap on the strategy of buying votes, perhaps forcing wealthy minority interests to adopt other strategies, like persuasion. Most approaches to combating the seeming inevitability of democratic sclerosis rely on combatting money with money, but quadratic voting just looks to place a ceiling on the value of the money.

Seems like this model would work best in a society without such sharply drawn lines between two parties. It does get me wondering whether some social network could be designed to try to optimize for more centrism. Are flame wars that just entrench both sides the inevitable outcome of all comment threads on controversial topics? Maybe it's built into the prevalent designs of online discussion threads.

Elon Musk AMA

On the eve of SpaceX trying to launch a rocket that will bring supplies to the International Space Station and then try to land itself (or at least its first stage) back on a barge in the ocean (NBD), Elon Musk did a Reddit AMA: First question:

TCEchicago
What daily habit do you believe has the largest positive impact on your life?

ElonMuskOfficial
Showering.

Also:

aerovistae 
tl;dr: How do you learn so much so fast? Lots of people read books and talk to other smart people, but you've taken it to a whole new level.

It seems you have an extremely proficient understanding of aerospace engineering, mechanical engineering, electrical engineering, software engineering, all various subdisciplines (avionics, power electronics, structural engineering, propulsion, energy storage, AI) ETC ETC nearly all things technical.

I know you've read a lot of books and you hire a lot of smart people and soak up what they know, but you have to acknowledge you seem to have found a way to pack more knowledge into your head than nearly anyone else alive. Do you have any advice on learning? How are you so good at it?

ElonMuskOfficial
I do kinda feel like my head is full! My context switching penalty is high and my process isolation is not what it used to be.

Frankly, though, I think most people can learn a lot more than they think they can. They sell themselves short without trying.

One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to.

Not the most scintillating of AMA's, but the man can be forgiven if his mind is elsewhere.

Sensory Ethnography Lab (SEL)

The most exciting documentary films being made today come not from a brand-name auteur or even some up-and-coming, Sundance-anointed visionary. Rather, they come from a place called the Harvard Sensory Ethnography Lab, which sounds more like somewhere an ophthalmologist might send you than a source of great filmmaking.

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Could the SEL be a model for a new kind of filmmaking? More and more budding filmmakers are taking affordable GoPro cameras and seeing what kind of images they can capture with them — attaching them to bikes, placing them on consumer drones, jumping out of airplanes with them, etc. “For a lot of people, these films are their first experience with experimental cinema, but they’re so impressed by it all,” says Krivoshey. “And I think that will have an enormous effect. Who knows what other films these people will see, and in some cases make, after seeing these films?”

But the unfiltered feel of SEL films is not achieved easily: It’s a product of academic rigor and a dedication to fieldwork and observation. The Lab was founded at Harvard in 2006 by Castaing-Taylor, an anthropologist by training. It’s an interdisciplinary program that admits around ten students a year, with a course called Sensory Ethnography. There are a couple of editing rooms that belong to the SEL, as well as equipment filmmakers can check out to take to distant corners of the world.  

Bilge Ebiri profiles a program that has produced some of the best, most groundbreaking documentaries ever.

I find many documentaries largely squander their medium, using a lot of footage of talking heads.  Sometimes archival footage isn't available, but relying on talking heads to provide the running narrative is not much of an improvement on reading the story, and often it's worse. While it's great to hear people's voices, see their face and body on the big screen, over reliance is a dull affair. I saw so many such formally monochromatic documentaries at Sundance before I just decided to steer clear of the category and wait to hear what was good before committing two hours of my time to one.

Leviathan, SEL's documentary about a North Atlantic fishing boat, was so far from a conventional documentary it left me in a trance. No voiceover, barely any dialogue, just long, unbroken shots from cameras tucked into a variety of nooks and crannies inside and outside one fishing trawler. Some of the images are so memorable I can still summon them from memory nearly two years after first viewing: one shot of fish from the most recent catch sliding back and forth on the deck of the boat as it sways to and fro in the ocean, many of the fish still gasping for air (or water, as it is); another shot of blood, discarded appendages and innards, and ocean water—the other accumulated detritus of the catch—spewing out of the side of the boat, as if the trawler itself were some Biblical leviathan, defecating into the ocean. If it weren't so expensive to have flat screen TVs running 24/7 all over my apartment, Leviathan is one of the things I'd have playing on them on a loop, a constant reminder of how alien life on this earth can be.

A lot of the footage wasn't high definition the way people are accustomed to these days (look at all the negative Amazon reviews complaining about picture quality), but they are gorgeous and awe-inspiring. And the prospect of long, uncut shots with no dialogue or voiceover is not for everyone. Frankly, it's not for most people. You've been forewarned.

However, if you, too, are tired of the same, overproduced documentary style, the one that prevails not just at film festivals but in movie theaters and on television, I highly recommend the work of the SEL. If you have a Netflix account, you can stream SEL's latest work Manakamana, a series of unbroken shots from a fixed camera perched in a cable car carrying pilgrims and tourists up to a Hindu temple atop a mountain. No one can accuse the SEL's documentary descriptions of selling too hard, but that is of a piece with their cinematic approach.

Unlike most conventional documentaries, in which every production choice feels like a shove towards the filmmakers' judgment, SEL's films both bring you into aching proximity with their subjects (the long, continuous shot is perhaps one of the greatest challenges for the modern short attention-span brain, but I think of it as a form of visual meditation and immersion) and yet render them mysterious and alien (the lack of any voiceover, title cards, or explanatory narrative means your'e dropped into a world and expected to figure everything out, Myst-style). In doing so, SEL transports the audience closer to the nature of truth, in all its slippery contradictions and Moebius-like contours, than any other documentaries being made today.