## Rock Paper Scissors Strategies.

Since people act predictably irrational, the Chinese game researchers were able to identify the following strategies for a sure victory:

• The first strategy is the countertactic: Let’s say you played scissors and your opponent played rock. The chance that your opponent will confidently play rock again is now very high. What that means to you: anticipate that and play paper. In other words: play the option that wasn’t played in the previous round.
• The second strategy is to mirror: If you just won, play what your opponent just played, because he or she will think that you are going to play the same gesture again.

Therefore, this is the best way to win at rock-paper-scissors: if you lose the first round, switch to the thing that beats the thing your opponent just played. If you win, don’t keep playing the same thing, but instead switch to the thing that would be beaten by the thing that you just played. In other words, play the hand your losing opponent just played. You should switch to scissors. This should work unless your opponent has read this article, in which case, you both are in trouble because you’re now living on a plane of RPS strategy the likes of which we can only imagine.

Here’s how it works in practice: Player A and Player B both start by using random strategies. If Player A uses rock and Player B uses paper, Player A loses. In the next round, Player A can assume that Player B will use paper again and should therefore use scissors to win. In the round after that, because Player B lost, Player A can assume that Player B will use the next strategy in the sequence — scissors — and Player A should then use rock, thus winning again.

If you take the game on a theoretical level, the most mathematically sound way to play rock-paper-scissors is by choosing your strategy at random. Because there are three outcomes — a win, a loss, or a tie — and each strategy has one other strategy that it can beat and one other strategy that can beat it, and we don’t care what strategy we win with, it makes the most sense to pick paper exactly one-third of the time, rock one-third of the time, and scissors one-third of the time. This is called the game’s Nash equilibrium.

The pattern that Zhejiang discovered — winners repeating their strategy and losers moving to the next strategy in the sequence — is called a ‘conditional response’ in game theory. The researchers have theorized that the response may be hard-wired into the brain, a question they intend to investigate with further experiments.

The strategy for playing RPS depends on how skilled your opponent is. Let me start by giving a basic strategy for playing against a novice player (which is to say, 99 percent of the public).

First of all, the throws are not equally common. Statistically, they are,