En Prison Rule for Roulette
“In prison”: even-money betbetEven-money betRed/black, odd/even, high/low. 18 numbers, e dey pay 1:1.Read di whole tin → wey zero catch go get one more spin instead make e lose.
For en prison roulette, dem go hold your chip; if di next spin win, you go collect your stake back (no winnings). For maths, e near la partage: house edge of about 1.35%.
How e dey go
ZerowheelZeroDi one green pocket wey no even-money, dozen or column bet dey cover; na im be di source of di house edge. Dem also dey call am: single zero, 0.Read di whole tin → land. Dem no sweep your $10 redbetRedEven-money bet on di 18 red numbers. For French: rouge.Read di whole tin → chipmoniChipToken wey stand for one fixed amount, wey you put on top di layout to make bet. Dem also dey call am: check.Read di whole tin →; di dealer go put marker on top am, or push am go di line of di box, to show sey e dey prison. Dem go play di next spin. Red: dem go release di chip and return am give you, $10, with no winnings. BlackbetBlackEven-money bet for di 18 black numbers. For French: noir.Read di whole tin →: di chip don lose. Zero again: e depend on di house rules. Some casinos go release half (wey be like la partageruleLa partageFrench rule: when zero come out, dem go return half of even-money stake. E dey cut di house edge for dose bets into half, to 1.35%.Read di whole tin →), some go keep am for prison for anoda spin, and few go just collect am.
Zero land. Dem mark your $10 for red as “en prison”.
Dem release di chip. $10 come back, no winnings. Net for di two spins: $0.
Di chip don lose. Net: −$10.
E depend on di house: e go stay for prison, dem go return half, or e go lose.
Di calculation
For di spin wey follow zero, di chip wey dey prison go win back im stake with probabilitymathsProbabilityDi chance of one outcome, from 0 to 1 or from 0% to 100%. One number: 1/37 = 2.70%.Read di whole tin → 18/37 and e go lose with probability 18/37 (if we no count wetin second zero go do). So im expected valuemathsExpected valueDi average result for each bet for di long run. −1/37 of di stake for every standard European bet.Read di whole tin → na about half of di stake, di same tin as la partage wey dey return half sharp sharp. If second zero go make di chip lose, en prisonruleEn prisonFrench rule: when zero come out, dem go hold even-money bet for di next spin instead make e lose. E dey cut di house edge for dose bets into half.Read di whole tin → dey small worse pass la partage: 1.39% against 1.35%. If second zero just keep di chip for prison for anoda spin, di two na di same. For di strict French rule, second zero go send di chip one level go down, and e go need two wins before e fit comot: 1.37%. Di difference small reach make you no worry about am when you dey choose table.
Why di rule dey
Roulette en prison na di older one for di two French rules, and e start as respect wey casinos for spa towns of di 19th century dey give pipo wey dey come regular. La partage na di modern, simple version: di same value, no need to keep record, no argument about chip wey dem leave for di line. For history, Monte Carlo tables dey allow di player choose when zero land; today most tables dey use one rule by demself.
How e dey touch your own rules
If you dey use stop-lossstrategyStop-lossOne amount of loss wey you set before, wey you go end di session when you reach am.Read di whole tin → or you set fixed number of spins, chip wey dey prison na bet wey you no choose to make for di next spin. E be small tin, but na di only time for roulette wey di table go make decision for you.
Questions wey pipo dey ask
No. E go stay until di next spin settle am. Some houses go allow you collect half instead, and dat one na la partage by anoda road.
No. Na only even-money bets, like la partage.
Dem be di same, di difference no reach 0.04%. Take anyone wey di table offer.
Play with Maths
Try dem by yourself first. Each solution dey folded; open am when you ready.
Under en prisonruleEn prisonFrench rule: when zero come out, dem go hold even-money bet for di next spin instead make e lose. E dey cut di house edge for dose bets into half.Read di whole tin →, even-money betbetEven-money betRed/black, odd/even, high/low. 18 numbers, e dey pay 1:1.Read di whole tin → wey zerowheelZeroDi one green pocket wey no even-money, dozen or column bet dey cover; na im be di source of di house edge. Dem also dey call am: single zero, 0.Read di whole tin → catch dey get one more spin: win dey return di stake, any oda tin dey lose am, second zero inside. Work out di house edgemathsHouse edgeDi part of each stake wey di casino dey keep for average: 2.70% for European roulette.Read di whole tin →.
Show di solution
Answer 19/1,369, wey be about 1.39%.
Take $1 on redbetRedEven-money bet on di 18 red numbers. For French: rouge.Read di whole tin →. E dey win straight with chance 18/37: +1.
Zero dey come out with chance 1/37. Then di next spin dey return di stake with chance 18/37 (net 0) and e dey lose am if not. So di bet dey lose with chance 18/37 for di first spin, plus 1/37 × 19/37 afta zero: 666/1,369 + 19/1,369 = 685/1,369.
Expected valuemathsExpected valueDi average result for each bet for di long run. −1/37 of di stake for every standard European bet.Read di whole tin →: 666/1,369 − 685/1,369 = −19/1,369 ≈ −1.39%. La partageruleLa partageFrench rule: when zero come out, dem go return half of even-money stake. E dey cut di house edge for dose bets into half, to 1.35%.Read di whole tin → dey give back half immediately and e dey cost 1/74 ≈ 1.35%: di second zero na di whole difference.
Small laugh
Freedom, but winnings no dey.
Sources
- Ethier, S. N. The Doctrine of Chances: Probabilistic Aspects of Gambling.
- Wykes, A. The Complete Illustrated Guide to Gambling.
- Wizard of Odds. “Roulette Basics.”