View source for Choboichi

{{One source|date=December 2024}}
{{nihongo|'''Choboichi'''|チョボイチ||<!--{{lit|one die}}-->also written as チョボ一, ちょぼいち, or 樗蒲一}} is a simple gambling game played in Japan using one covered [[dice|die]]. The dealer shakes a six-sided die in a cup or rice bowl and then places it upside down, concealing the rolled value; after the players wager for their prediction of what the value will be, the dealer reveals the die by lifting the cup.

==Gameplay==
{|class="wikitable floatright" style="width:6em;font-size:250%;text-align:center;"
|-
! style="font-size:40%;" colspan=3 | Choboichi game board
|-
| 1 || 2 || 3
|-
| 4 || 5 || 6
|}
The dealer is known as the {{nihongo|dōtori|筒取}}, while the bettors are the {{nihongo|hariko|張子}}; the dealer is the one who holds the cup, known as the {{nihongo|tsubo|壺}} or {{nihongo|tsubozara|壺皿}}. The role of the dealer may either be fixed to one person or rotate amongst the players.<ref name=Ameba>{{cite web |url=https://ameblo.jp/t-edo09okazu/entry-11067948871.html |title=樗蒱一(チョボイチ) |lang=ja |trans-title=Choboichi |date=November 3, 2011 |website=Ameba |access-date=9 January 2025}}</ref>

Players wager by placing money on one of six spaces on the game board. Winning wagers are paid out typically at four-to-one (e.g., a player who places a $10 bet on a winning space would be paid $40) while the dealer keeps the losing bets.<ref name=Arai>{{cite web |url=https://dice.saloon.jp/dice/gamble.html |title=さいころ賭博 |lang=ja |trans-title=Gambling games using dice |first=Satoshi |last=Arai |website=dice.saloon.jp |access-date=25 December 2024}}</ref> The winning payout may vary between 2:1 and 5:1.

Consider a player who places a total bet of {{JPY|600}}, with {{JPY|100}} wagered on each space: one space will win, and the player will receive {{mvar|M}}×{{JPY|100}} for that bet, but the other five spaces will lose, costing the player {{JPY|500}}. The difference between the amount the player loses and the amount won is the [[house edge]]; with a multiplier of 4, that difference is {{JPY|100}}, which is {{frac|6}} ({{#expr:100/6 round 1}}%) of the initial {{JPY|600}} bet. Formally, the [[Gambling mathematics#House advantage or edge|house edge is computed]] using the relative probabilities of winning and losing along with the winning multiplier, {{mvar|M}}:

:<math>
Edge = \frac{(P_{lose} \cdot Bet) - (P_{win} \cdot M \cdot Bet)}{Bet} = \frac{5}{6} - \frac{1}{6} \cdot M
</math>

The house edge varies from {{#expr:100*(5-2)/6 round 1}}% (for a multiplier of 2) to {{#expr:100*(5-5)/6 round 1}}% (for a multiplier of 5), with the most common multiplier of 4 resulting in a house edge of {{#expr:100*(5-4)/6 round 1}}%.

There are multiple variations using up to five dice,<ref name=Arai/> although multiple-dice games generally have different rules, including [[Chō-han]] (2 dice) and [[Cee-lo]] (3 dice).<ref name=Ameba/>

==History==
The game was noted to be so popular by the 18th century that an entire strip of gambling sheds one {{transl|ja|ri}} long, {{cvt|3.75|km}}, was dedicated to it.<ref>{{cite news |url=https://www.japantimes.co.jp/community/2002/04/07/general/a-dicey-history/ |title=A dicey history |first=Mark |last=Schreiber |date=April 7, 2002 |newspaper=The Japan Times |access-date=24 December 2024}}</ref>

===In culture===
At least two {{transl|ja|[[rakugo]]}} stories use choboichi as a central element: {{ill|One for Show|ja|看板のピン}} and {{nihongo|"Tanuki Dice"|狸賽|Tanuki Sai}}.<ref>{{cite web |url=https://jbmbkyo.blog.fc2.com/blog-entry-2712.html |title=看板のピン |lang=ja |trans-title=One for Show |date=February 21, 2011 |author=藪さん |website=藪井竹庵 |access-date=9 January 2025}}</ref>

==References==
{{reflist}}

==External links==
* {{youtube |id=N8pf93cW5ts |title="One for Show" rakugo in English}} by Hiroyuki Otomo

{{Dice games}}

{{dice-game-stub}}
[[Category:Dice games]]
[[Category:Japanese games]]
[[Category:Gambling games]]
[[Category:Gambling in Japan]]