Crowds – Blinkers vs.Thinkers

January 6, 2015
Posted by Jay Livingston

Most of the wisdom-of-crowds posts in this blog have been about sports betting. The trouble there is that no matter how many people are betting,  they have only two choices – the favorite or the underdog. To see whether the crowd is wiser than the experts, you’d need data on many, many games.

The original wisdom-of-crowds test was a weight-guessing contest, so the crowd had an infinite number of choices – not just Colts or Bengals but all weights from one pound on up.

Plymouth, England, 1906. On display is an ox, slaughtered and dressed. How much does it weigh? Fairgoers submitted their guesses. A statistician, Francis Galton, happened to be there and recorded the data. Galton was also a eugenicist, so he was certain that the guesses of the masses would be less accurate than those of the experts. But it turned out that the crowd, as a group, was far more accurate. The average of all the guesses (n=787) was within one pound of the actual weight (1,198 lbs). No individual guess came that close.

In a blog post many years ago, I mentioned (here) that I was going to try to replicate the study but with the students in my class replacing the fairgoers, and instead of ox, a jar of M&Ms.  I did, and it proved to be another failure to replicate. The class mean was way off, but mostly because of one outlier, a girl whose guess was an order of magnitude higher than the others. Besides, the sample size, about 20 students, was too small.

Now, Erik Steiner, a geographer at Stanford, has gone Galton using the coins his parents had been tossing into a jar for the last 27 years.  Steiner crowdsourced guesses to the entire Internet. He posted the contest on the Stanford Website, and then Wired reposted it.

Photo: Susie Steiner

He got 602 guesses,* not exactly the entire Internet, but enough for data analysis. Here is his summary:

I won’t bore you with the finer points of asymmetric non-parametric one-sample T tests, but let’s put it this way: The crowd was waaaay off.

The value of the coins in the jar was $379.54. The average of the guesses was $596.12 – a difference of $216.58, or 57%.

Steiner’s results don’t give much support to the crowd. But the experts, those who tried to be the smart money, were even shorter on wisdom.

. . . people who claim to have done some math were far less accurate (X =$724.81) than those who made a snap judgment (X =$525.02). This may explain why estimates submitted from .edu or gmail addresses were less accurate than guesses submitted from hotmail and yahoo addresses.

Here is Steiner’s chart of the data.

(Click on the chart for a larger view.)

Steiner refers dismissively to “all that Gladwellian snap-judgment stuff.” But even he has to admit that the blinkers did better than the thinkers. In fact, the crowd median, rather than the mean, was pretty close to the actual value.  Without those thinkers who “actually did the math,” the median and mean would have been even closer to the mark.

(Steiner’s write-up, along with charts and links to the data, are at Wired – here.)

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* I’m not sure what to make of these response rates. Steiner sent his query out to potentially the world, but his crowd turned out to be smaller than the one that whose guesses Galton talled that day at the fair. I guess it’s a matter of whose ox is scored.

Becker in Paris

January 5, 2015
Posted by Jay Livingston

You know what the real problem with Bourdieu was? The real problem with Bourdieu was that he was a schmuck – power-hungry and mean in spirit and obsessed with career.

Now that I’ve got your attention . . .  Yes, I suppose that’s the money quote in Adam Gopnik’s profile of Howie Becker in the latest New Yorker (here). Most of the article, thankfully, is not about character assessment (or assassination). It’s about sociology – American sociology as practiced by Howe Becker.

Gopnik interviews Becker in Paris, at his apartment in the 5^ème and at a nearby resto. I had not known that Becker has a following in France, unexpected given his preference for starting with ground-level data – what people do and say.

The important difference between Becker and European sociologists (and many American sociologists too) is Becker’s commitment to “exotic beauties of empiricism” (Gopnik’s phrase, not Becker’s). “He’s resolutely anti-theoretical and suspicious of ‘models’ that are too neat.”

Becker never starts by laying out theoretical concepts; he starts with people doing something together – playing music,* getting high, studying medicine. When he does move to a slightly more theoretical plane, it’s to point out something that is fairly simple but that most people seem to be overlooking. Until Outsiders (1963), much writing about deviance and crime started from the question, “Why do those people do those weird or bad things?” Becker reminded us that deviance is a process; it involves not just breaking rules but also creating and enforcing those rules, and that we should study the motives and methods of the “moral entrepreneurs” as well as those of the deviants.

The “why” question focuses all attention on the deviant. It also leads to theoretical abstractions. Becker asks “how,” which focuses attention on what people actually do.

Gopnik, by the way, is sensitive to this France/America divide over the primacy of facts or theory. As an American journalist in Paris, he had to fact-check an article, only to find that the French were completely unfamiliar with this job.  “What do you mean, une fact checker?”

There is a certainty in France that what assumes the guise of transparent positivism, “fact checking,” is in fact a complicated plot of one kind or another, a way of enforcing ideological coherence. That there might really be facts worth checking is an obvious and annoying absurdity; it would be naive to think otherwise.**

For Becker, checking the facts, even the ordinary ones, and thinking carefully about them is not only necessary; it is what eventually leads to sociological insight.

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*I had always assumed that Becker was a competent but ordinary jazz pianist. In Outsiders, he refers to the musicians he played with (and got high with) as “dance musicians.”  Now, thanks to Gopnik, I discover that he studied with the extraordinary Lennie Tristano.
 
**From Paris to the Moon (2000). An earlier blog post on facts and theory in France and the US is here.

The Wisdom of Crowds vs. The Smart Money - Again

January 4, 2015
Posted by Jay Livingston

Several posts in this blog have looked at the “wisdom of crowds” in football betting. In brief, the wisdom of crowds idea asserts that the collective opinions of the many are more accurate than the opinions of a few experts. (For a fuller explanation, see this post from 2009.)

Today’s playoff game between the Bengals and the Colts provides an example. The crowd loves Indianapolis.  Two-thirds of bets have been coming in on the Colts, who opened as 4-point favorites.  Nevertheless, early in the week, the line went down to 3 ½.  Apparently, the bettors who the bookies most respected, were taking the Bengals, even though the Bengals' star receiver, A. J. Green will not be playing.

Today, the public has continued to bet the Colts, with the result that some books have raised the line back to 4. 

The smart money is still on the Bengals. But if you believe in the Wisdom of Crowds, you should be on the Colts.

UPDATE:  The smart money wasn’t. The crowd was wise. The Colts easily beat the Bengals 26-10.

Names Ending in N

January 3, 2015
Posted by Jay Livingston

A post at FiveThirtyEight (here), by Nate Silver and Allison McCann, has the title, “How to Tell Someone’s Age When All You Know Is Her Name.”* But if the person in question is a male, you might make an equally good guess with one letter – the final one.

In a 2009 post (here), I had some graphs showing the rise of boys names that end in the letter N.

 That trend that had gone largely unnoticed, probably thanks to the availability heuristic.  It’s much easier to think of names and words that start with a given letter rather than those that have that letter elsewhere. Especially with names, we’re more likely to think in terms of initials.

Those data were from 2006. The trend has continued in strength. The FiveThirtyEight post shows the historical change in a slightly different way. Instead of looking at the popular names in each year, Silver and McCann show the age range of people with each name.  Here are the twenty-five oldest names.  The graph shows the median and the inter-quartile range. For example, the median Willard is 65 (the median for all males is about 37); half of all Willards are between ages 51 and 75.

And here are the youngest 25.

Among the oldsters, only Norman and Herman sport the final N. But in the 3-10 median age group, 14 of the top 25, including eight of the eleven youngest, end in N. 

I am at a loss as to how to explain this. It could just be one of those cases of unintentional and unconscious influence. With some names, the imitation with slight variation is more overt – Aidan, Jayden, Brayden, Kayden, et al. But for those others – Landon, Mason, Julian, and the rest – maybe there’s something about that final N that, like the music of Mumford and Sons or Kings of Leon, sounds just right to the ears of 21st-century parents.

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* The post appear May but was recently tweeted, which is how I discovered it.