Any poker professional (or extremely devoted amateur) must master his expression. Unfortunately, it’s your hands that might give your hand away.
In a new study published in Psychological Science, Stanford University’s Michael Slepian found that even the most stone-faced poker player can be beaten by watching his hands. Slepian and his colleagues showed 78 undergraduates videos of players placing bets at the 2009 World Series of Poker. Some videos showed only the player’s face, some only the player’s arms and hands, and some showed every part of a player sitting at a table, chest up.
After each viewing, subjects guessed how strong a player’s had was on a seven point scale. When shown a just player’s face, subjects were a poor judge of the strength of the player’s actual hand. In fact, there was a negative 0.07 correlation, meaning that there was a statistical tendency for subjects to think hands were good when they were not.
When shown videos of everything about a player from the chest up, the correlation went away. However, when shown only a player’s arms and hands, there was a 0.07 positive correlation between a subject’s guess and reality.
In a follow-up test, Slepian had the undergraduates view videos of the player’s hands and arms, and rate them based on how smoothly they bet their chips. His discovered that confident players pushed their chips smoothly, whereas unconfident or bluffing ones did not.
So, the next time you’re bluffing away people’s money at the poker table, it isn’t your poker face you’ve got to pay attention to—steady those hands.
[A Handy Tip – The Economist]