Science and Tech


Here's How To Win At Rock-Paper-Scissors, Life

A new study shows principles of game theory can be applied to rock-paper-scissors, so you can fearlessly challenge everyone you know to RPS.
Posted at 10:36 AM, May 02, 2014

This could be the most important strategy you'll ever learn: how to win at rock-paper-scissors. Oh, yeah — it's on. 

Scientists at the Zhejiang University in China studied hundreds of throwdowns between 360 participants to put some actual science in the game. The players were given money for wins. (Via YouTube / Videojug)

Before, it was thought players used the Nash equilibrium strategy, where they randomly thew out each of the three options an equal number of times in order to confuse opponents — essentially making RPS a game of luck. (Via Nature World News)

Turns out, it's much more of a mind game than you ever gave it credit for.

Here's what the scientists found: It doesn't really matter what players pick the first round — that's where it's pretty random. Here's a hint, though. Rookie males will usually pick rock to start with. (Via YouTube / The Orchard Movies)

Winning players followed a general rule of "win, stay; lose, shift," meaning if they won a round with rock, they'll stick with rock for the next round. But if they lost, players followed a predictable pattern of what they chose next. (Via The Washington Post)

That pattern is a clockwise direction of power. It's kind of confusing, but basically it goes like this: rock at the top, paper beating rock, scissors beating paper, rock beating scissors, and we're back to the top. 

So, this means if you lose to rock the first round, the next round you should probably play paper. Since your opponent will probably be all confident and stick with rock, you'd win! (Via Wikimedia Commons / Enzoklop)

According to MIT Technology Review, the strategy follows a game theory principle called conditional response, and it hasn't been observed before in the game before now. 

But Ars Technica explains the million-dollar advice: If you win, don't stay with your choice. Instead, throw what will beat what your opponent will most likely move on to. 

So, if you win with scissors, a smart opponent will probably play rock next. That means you should go with paper. (Via Wikimedia Commons /Seriton)

And just so you know, when you play RPS, you're playing the same game used by members of the Han dynasty in China between about 200 B.C. and 200 A.D. Pretty cool, huh?