Sunday, April 14, 2013

Poker and the problem of the social sciences

Recent research found that arm movements in poker players were more informative about the players' hands than their faces were.
Test subjects were non-experts in poker. They were shown three different types of footage of players at a poker championship:
  1. Showing just the faces
  2. Showing just the arms and hands moving chips into the pot
  3. Showing the whole upper body
The test subjects had to guess how strong a hand the players had.

When they saw the whole upper body, they did no better than chance.

When they saw just the face, they did worse than chance.

And after those two observations, you may not be surprised to learn that when they saw just the hands, they did better than chance.

The researcher's hypothesis was that players who were confident about their cards would have less anxiety and this would show itself in smoother arm movements. The evidence he gathered seems to support that idea.

These were expert poker players--the footage was from the 2009 World Series of Poker--so it seems they've learned not merely how to hide the quality of their cards through a stoic "poker face"; they can actually use their face to lie to you. But their arms still give them away.

Neither the HuffPo article nor the NPR story I heard this morning drew the conclusion that seemed obvious to me. As this knowledge spreads, there will certainly be hard-core poker players who start paying attention to their arms. They'll try to learn to control their arms so that they can bluff just as well with a limb as with a lip.

It may be that the connection between anxiety and smooth motion is harder to overcome than the facial tells they've already mastered, but it would be surprising if there weren't some improvement possible.

And if that happens, think about what will have happened here.
It's likely that the best poker players have been so good in part because they've been picking up on the arms. It could even be a subconscious thing: a very attentive player might tune in to a "feel" he has and get very good at using it, without being aware that this "feel" is being triggered by a subconscious observation of arm movements.

And now that edge will diminish. Any hard-working poker player will learn to observe her opponents' arms and control her own. Eventually, all the best poker players will have mastered this new way of deceiving their fellow humans while trying not to be deceived.

Deception is hardly unique to humans--just ask my colleague Stan Sessions about salamander mating rituals.

There's one species where a male near a receptive female lifts his tale and starts walking. If she comes along behind and nudges his behind, he keeps going, until eventually he deposits a little capsule of sperm. The pair keep moving, until the female is over the sperm; she gets herself lined up just right over the sperm, so they can enter her cloaca and fertilize her eggs. The sneaky strategem is for a second male to butt into the process, displacing the female in the role of nudging the first male's posterior. The first male thinks he's still got a good thing going. The female isn't too disturbed by the change in smell from one male to the other, and so the three of them proceed. The first male deposits his sperm capsule, and then the second male deposits his own sperm capsule right on top of the first one! Stan has seen stacks of sperm capsules several capsules high.

Pretty sophisticated--and bizarre. But salamanders don't observe their own mating behavior and consciously set out to invent a way to "game the system." We do. Say someone notices a regular pattern in how stock prices move and they build a trading strategy. They'll be successful so long as not too many other people figure out the same signal and try to use it as well.

Our understanding of geological processes has no effect on how rocks actually form and break down. In contrast, our understanding of how an economy works is part of a two-way relationship with how an economy actually works. We learn about an economic phenomenon, so we change our behavior, so the economic phenomenon changes as well.

The same thing happens in politics: we learn about patterns of political behavior, then political strategists use those insights to develop new campaign tactics, and we may find that the underlying political behavior has changed.

From one angle, this kind of arms race is nothing new. Darwinian evolution can be seen as an arms race, too. What's different, as suggested above, is that we're thinking about it. Instead of stumbling across a new "weapon" by chance and then having it selected by differential fitness, we actively seek out new strategies to help ourselves in whatever activities are important to us.

As social scientists, we're aiming at a moving target. It would be nice to find some sort of bedrock, which may be why I'm drawn to biophysical economics, or more generally in an evolutionary, ecological understanding of the economy.


  1. On behalf of salamanders everywhere, I thank you for dragging them (and me) into this interesting discussion.

    1. You're most welcome--and thanks for telling me about strange salamander sex. (Did I get it mostly right?)

      From your perspective on the other side of the line between social and natural sciences, what do you make of this difference that we can intentionally pursue our "arms races"?

  2. If what you mean by "intentionally" is that we think about what we are doing (consciously plot), that is also within the plastic behavioral repertoire of some non-human animals (apes, birds, other mammals probably). And, of course, we humans are also engaged in our own unintentional arms races. For example (staying on sex for the time being), I am thinking of experiments showing that sperm counts in human males of "mated pairs" vary according to the percieved probability of extra-merital copulations on the part of the female (positive correlation). We should also chew on the differences between genetic adaptive evolution and cultural adaptive evolution (e.g. monkeys learning by watching to wash their sandy rice grains, house sparrows learning to pop the tops of milk bottles, etc.). I recommend E.O. Wilson's new book: The Social Conquest of the Earth.

    1. It seems like it's often a fuzzy line between things that are just different points on a spectrum and things that are actually new.

      Yes, animals display some intentionality, and we display plenty of unintentionality. But is it fair to say that our intentionality is more far-reaching and common than that of other species?

      And then there's the notion of consciously trying to understand how things work, with the results of that effort becoming part of our arms race. Is that also just another point on the same spectrum, or is it actually just something new?

      Yeah, I've gotta read Wilson's book.

  3. I really enjoy reading and also appreciate your work.