Janken: How Japan Plays Rock Paper Scissors
Guu, choki, paa. How janken is played in Japan, what "saisho wa guu" and "aiko desho" are for, where the game came from, and the games that follow it.
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News, strategy, and updates from the Rock Paper Scissors community. 47 articles.
Guu, choki, paa. How janken is played in Japan, what "saisho wa guu" and "aiko desho" are for, where the game came from, and the games that follow it.
How the University of Tokyo janken robot wins every time, why that is speed, not prediction, and how pattern-reading AI beats people at Rock Paper Scissors.
Who invented Rock Paper Scissors Lizard Spock, why Sam Kass and Karen Bryla added two throws, and how The Big Bang Theory made it famous in 2008.
How to make the rock, paper and scissors hand signs correctly, common variants and fouls, their names around the world, and where the gestures came from.
Real, documented decisions made by rock paper scissors: the 2005 Christie's vs Sotheby's art consignment, a 2006 federal court order, and actual prize money.
The Bob's Burgers rock paper scissors episode, the MLB and high school rain-delay games, Kaiji, Squid Game and The Big Bang Theory, with real details.
What the evidence actually says about gender, age and rock paper scissors: which claims come from real data, which are folklore, and what our own throws show.
No throw wins more by itself, but people do not throw at random. Real data on rock, paper and scissors frequency, and how to use it against human players.
The documented history of Rock Paper Scissors: shoushiling in a Ming-era book, mushi-ken and jan-ken in Japan, and its arrival in Western papers in the 1920s.
How Rock Paper Scissors is named and played in Japan, Korea, Indonesia and China, from jan-ken and muk-jji-ppa to ant-person-elephant and the old ken games.
The probabilities behind rock paper scissors: win, tie and loss odds, expected value, why one-third each is the Nash equilibrium, and tie odds for groups.
Why WRPSA named BTS its rock paper scissors ambassadors, and the Run BTS moments behind it: Suga reading Jungkook in episode 96 and V's fake call in 127.
A single throw of Rock Paper Scissors is luck. Over many throws, human habits make skill matter. What bot contests, lab studies and our own data show.
What the 2017 Kyoto University study in Primates found: five of seven chimpanzees learned the rock paper scissors rules, performing like 4-year-old children.
Is there an official Rock Paper Scissors world ranking? Who has kept rankings, how Elo ratings work for RPS, and exactly how WRPSA rankings are calculated.
Rules for the Rock Paper Scissors variations people actually play: Lizard Spock, RPS-7, RPS-15, RPS-101, Bear Hunter Ninja, muk-jji-ppa and game-night picks.
The real books about rock paper scissors worth reading: the Walker brothers strategy guide, a game theory book, and a picture book, with who each one suits.
Where the Dwayne "The Rock" Johnson rock paper scissors meme came from, when he recreated it himself in 2018, and why RPS memes keep working.
How tournament Rock Paper Scissors is refereed: the count, false starts, late throws, illegal shapes, best-of formats, disputes, and how these rules came about.
How to find a real Rock Paper Scissors tournament near you, what happened to the big championships, and how to start one if nothing exists locally.
How to teach young kids rock paper scissors step by step, plus classroom activities that use the game for turn-taking, fair play, math and social skills.
Hand games, video games and strategy games that use the rock-beats-scissors loop, from mushi-ken and muk-jji-ppa to Pokemon, Fire Emblem and Age of Empires.
How the World RPS Championship grew from a Toronto bar event in 2002 to TV, who won every year, the $50,000 USARPS era, and why it ended in 2009.
A roundup of the Rock Paper Scissors memes that keep coming back: The Rock pun, Lizard Spock, RPS-101, "how does paper beat rock", and the auction twins.