Revealed: The Science of Winning at 'Rock-Paper-Scissors'
Researchers from China have just released a winning strategy for one of the most simple yet arguably greatest games ever played by humankind: rock-paper-scissors.
The study, posted on the arXiv.org database owned and operated by Cornell University, was led by three scientists at China's Zhejiang University who recruited 360 undergraduate and graduate students and directed them to play a total of 300 rounds of the schoolyard game while their actions were being recorded.
It was discovered that when a student won a round, it was after he or she tended to stick with the same action, instead of switching to another.
As well, when a student lost a round, it was noticed that he or she had most often switched to another action, rotating from rock to paper to scissors.
Therefore, the study said, if a player can think fast enough during each round's three-second countdown, he or she can anticipate their opponent's next move, based on how they fared in the previous round: whether they won, and, hence, would likely stay with the same action -- or lost, and would probably switch to the next action, in the predictable rock, paper, scissors order.
The new findings seem to cut up previous notions that rock-paper-scissors follows classical game theory, or mixed-strategy Nash equilibrium, "in which every player chooses the three actions with equal probability," the study authors wrote. Instead, those who win at the game appear to demonstrate "collective cyclic motions" and "conditioned response."
Put another way, you probably can claim the title of local rock-paper-scissors champion if you keep the scientific model in mind.
"Our theoretical calculations reveal that this new strategy may offer higher payoffs to individual players in comparison with the NE mixed strategy, suggesting that high social efficiency is achievable through optimized conditional response," the authors wrote, adding they plan to use their game insights to test other aspects of human psychology.
"Whether conditional response is a basic decision-making mechanism ...or just a consequence of more fundamental neural mechanisms," they said, "is a challenging question for future studies."