Game of the Month: Rock, Paper, Scissors

by Dagonell the Juggler

A News of the Weird column (http://www.newsoftheweird.com/archive/nw060507.html) mentioned that the U.S. Rock-Paper-Scissors Championship had been held in April in Las Vegas of that year. First prize was $50,000. The winner went on to represent the U.S. in the World RPS Championship held in Toronto, in mid-October. This inspired me to write this month's article.

The 'game' is actually a selection method, normally played to settle minor decisions such as which player goes first. similar to coin tossing or drawing straws. See my article "Odds and Evens" for a similar such game. In the SCA Kingdom of the Outlands, Rock-Paper-Scissors is known as "Outlandish Combat" and is often used to settle the dispute of which rattan blow landed first.

The Rules:

It's a two player game. The two players shake their fists in unison three times (called 'priming') and on the third throw hold out their hand in one of three configurations; a fist "rock", flat "paper", or first and second finger extended and spread "scissors". Scissors wins over paper ("scissors cut paper"), paper wins over rock ("paper covers rock") and rock wins over scissors ("rock breaks scissors"). Ties are re-played.

Strategy: [From Wikipedia]

"In order to prevent the unconscious forming of patterns after many hours of competition, and to combat many psychological techniques used in competitive play, a professional player may often employ the use of Gambits. A Gambit is a predetermined series of throws. Gambits may also be used in an attempt conceal or minimize tells. A serious combatant may practice a Gambit thousands of times until the mind has only to name the series of throws and muscle memory takes care of the rest. Much as a great martial artist or dancer will practice the same techniques until their conscious higher minds are not needed, and rather it is the lower unconscious mind which takes control. Mathematically there are 27 possible Gambits. While local names may vary there are eight internationally recognized and labeled Gambits."[Wikipedia,2006]
The Avalanche: Rock Rock Rock
The Bureaucrat: Paper Paper Paper
The Toolbox: Scissors Scissors Scissors
The Crescendo: Paper Scissors Rock
The Denouement: Rock Scissors Paper
Fistful O' Dollars: Rock Paper Paper
Paper Dolls: Scissors Paper Paper
Scissors Sandwich: Paper Scissors Paper

History:

The oldest recorded appearance of the game is in the book "Wuzazu" which was written by Xie Zhaozhi in the Ming Dynasty. According to the author, the game was called Shoushiling, meaning "hand command" and was played in the Later Han Dynasty (c 200B.C. - 220A.D.). 19th century writers refer to it as an Asian game. [Wikipedia, 2006]

In contrast, Douglas Walker of the World RPS Society (http://www.worldrps.com) suggests that the game somehow made it to Europe by the mid-1700's where it came to be associated with Jean Baptiste Donatien de Vimeur, Comet de Rochambeau. Jean was the French general who commanded an army that supported George Washington during the American Revolution. Why the game is associated with him is a mystery, but the game is also known as "Roshambo" in Europe [Straight Dope, 2001]

Additionally,

"Current research undertaken at the University of Lisbon by Baltasar Rui Delfim, soon to be published in Nature and Time, has shown that the origins of the game of Paper, Scissors and Rock (Pihedra, Papelsh e Tijhera) can be attributed to Celtic settlers in the northern regions of Portugal, near the Portuguese/Spanish border, around the 6th century BC. . . . It is believed that the game spread to the rest of Portugal in the 3rd century BC and to the rest of the Spanish peninsula over the next 50 years. Roman invasion of Hispania in the 1st century AD made the game popular in Gallia and Italia. However, the Romans did not introduce the game to the UK because they believed that the game could make the UK colonies rebel against the Senate and it was not until the Portuguese armada of 350 AD came to England that the game was properly introduced in Britannia." [World RPS website]

Not surprisingly, "professional" competitions are often held in taverns and sponsored by beer companies. The claim is often made that it's the only sport where "performance enhancing drugs" i.e. beer, is not only allowed, but actively encouraged. A list of upcoming "sanctioned" tournaments can be found on the both the USA RPS League (http://www.usarps.com) and World RPS Society (http://www.worldrps.com) websites. Alas, Western New York is far too provincial by world RPS standards, and no tournaments are scheduled for the near future.

The most expensive RPS game in history took place on April, 29th 2005. Takashi Hashiyama, president of Maspro Denkoh Corp., couldn't decide whether Sotheby's or Christie's should auction off four paintings estimated at $17.8M.

From USA Today:

"Kanae Ishibashi, the president of Christie's in Japan, declined to discuss her preparations for the meeting. But her colleagues in New York said she spent the weekend researching the psychology of the game online and talking to friends, including Nicholas Maclean, the international director of Christie's Impressionist and modern art department.

Mr. Maclean's 11-year-old twins, Flora and Alice, turned out to be the experts Ms. Ishibashi was looking for. They play the game at school, Alice said, 'practically every day.'

'Everybody knows you always start with scissors,' she added. 'Rock is way too obvious, and scissors beats paper.' Flora piped in. 'Since they were beginners, scissors was definitely the safest,' she said, adding that if the other side were also to choose scissors and another round was required, the correct play would be to stick to scissors - because, as Alice explained, 'Everybody expects you to choose rock.'

Sotheby's took a different tack. 'There was some discussion,' said Blake Koh, an expert in Impressionist and modern art at Sotheby's in Los Angeles who was involved in the negotiations with Maspro. 'But this is a game of chance, so we didn't really give it that much thought. We had no strategy in mind.'

Two experts from each of the rival auction houses arrived at Maspro's Tokyo offices, where they were shown to a conference room with a very long table and asked to sit facing one another, Mr. Rendell said. Each side's experts had an accountant from Maspro sitting with them.

Instead of the usual method of playing the game with the hands, the teams were given a form explaining the rules. They were then asked to write one word in Japanese - rock, paper or scissors - on the paper.

After each house had entered its decision, a Maspro manager looked at the choices. Christie's was the winner: scissors beat paper." [USA Today, 2005]

The four paintings in the auction were: Paul Cezanne's "Les grands arbres au Jas de Bouffan," estimated at $12 million to $16 million, sold for $11.8 million. Alfred Sisley's "La manufacture de Sevres," estimated $1.4 million to $1.8 million, sold for $1.6 million. Pablo Picasso's "Boulevard de Clichy" sold for $1.7 million, and Vincent van Gogh's "Vue de la chambre de l'artiste, rue Lepic" sold for $2.7 million. Both had been estimated to sell for around $2 million. Christie's normal percentage is 20% of the first $200,000 of each item and 12% on the rest. The winning game earned Christie's an even $1,000,000.

The University of Alberta's Department of Computing Science, put on a "roshambot" contest in 1999 and again in 2000. While it is trivial to write a program that makes one of three choices randomly, the winning programs kept track of opponent's previous choices trying to uncover patterns. The winner of the 1999 contest, "Iocaine Powder" (a reference to the 1987 movie "Princess Bride") used "Sicilian Reasoning" (ditto), an algorithm that explored six levels of choices for prediction methods.

If you'd like to try your hand at beating a computer at Rock, Paper, Scissors: http://chappie.stanford.edu/cgi-bin/roshambot

Update:

If you watch the TV series "Big Bang Theory" you may have seen the 'updated' version of this game, "Rock, Paper, Scissors, Lizard, Spock". Lizard is formed by putting your thumb under your fingers as if you were using a sock-puppet. Spock is done by using the Star Trek Vulcan salute. The game was invented by Sam Kass and Karen Bryla. Each choice beats two other choices and loses to the other two choices. The complete rules are as follows:

Bibliography

Jan Ken Pon (Rock Paper Scissors) History:
http://www.jbrowse.com/text/janken.shtml

News of the Weird:
http://www.newsoftheweird.com/archive/nw060507.html

Rock, Paper, Scissors -- Wikipedia:
http://en.wikipedia.org/wiki/Rock_paper_scissors

Rock, Paper, Scissors, Lizard, Spock -- Wikipedia:
http://en.wikipedia.org/wiki/Rock-paper-scissors-lizard-Spock

Roshambot (A Rock Paper Scissors playing program):
http://chappie.stanford.edu/cgi-bin/roshambot

Straight Dope Staff Report - What's the origin of "Rock, Paper, Scissors"?:
http://www.straightdope.com/mailbag/mrockpaper.html

USA-RPS League:
http://www.usarps.com/site/index.php

USATODAY.com - Rock paper scissors settles auction house battle:
http://www.usatoday.com/news/offbeat/2005-05-05-auction-game_x.htm

World RPS Society:
http://www.worldrps.com/