Know the Oddsspinner · Roulette strategy lab

Cash out: the stop that moves the typical session

Decide before you sit down how much profit you will walk away with: a modest target is reached most of the time, and a stop-loss at half the ladder limits the damage when it is not.

Chapter 7 of the spinner roulette research (chapters 0 to 9): Cash out: the stop that moves the typical session.

A cash-out ends the session the moment you are up the target, so the typical session is the target, a few dollars over. The lower the target, the more often you reach it before losing the ladder: c9 reaches $70 in 98.2 % of sessions, $280 in 93.2 % and $1,400 in 70.4 %.

A stop-loss at half the ladder ($2,459.50) costs three points of that chance (90.3 %) but cuts the worst 5 % from −$4,820 to −$3,210. Its sibling c8 with a $200 target and no stop-loss gets there more often (94.5 %) but keeps a worst 5 % of −$4,515. On Martingale red a half-ladder stop-loss never fires; stopping after seven losses does.

Open this chapter in spinner, with the interactive chartsTest your own system

The numbers

c9: chance of ending ahead by cash-out target (cycle wins)
TargetMeasuredPredicted (1 − q)^WTypical sessionAverage
5 wins98.2%98.2%+$77-$11.38
10 wins96.5%96.5%+$146-$27.46
20 wins93.2%93.1%+$286-$56.21
50 wins83.9%83.7%+$705-$142.92
100 wins70.4%70.0%+$1,404-$268.52
Worst 5 % of sessions with and without the stops
VersionChance of ending aheadWorst 5 % of sessionsAverage
c9, no cash-out67.1%-$4,820.13-$295.45
c9, cash out at 20 wins93.2%-$4,820.13-$56.21
c9, 20 wins + stop-loss90.3%-$3,210.44-$46.25
Martingale, 8 levels, cash out at 20 wins88.8%-$5,000-$113.80
Martingale, 7 levels + stop83.0%-$3,119.20-$87.03

Takeaways

The math

With a stop-win of W cycle profits a session ends ahead if it collects W cycles before a cap: P(win) ≈ (1 − q)^W ≈ e^(−q·W). c9, q = 0.00356: W = 5, 10, 20, 50, 100 predicts 0.982, 0.965, 0.931, 0.837, 0.700; measured 0.982, 0.965, 0.932, 0.839, 0.704. The median equals the target while P(win) > ½, that is while q·W < ln 2. The mean stays at −2.70 % of a smaller turnover: c9 at W20 wagers $2,157, mean −$56.21.

The half-ladder stop-loss is checked after the round, so it overshoots by one level: CVaR 5 % −$3,210, worst session −$3,275. Martingale red at W20: e^(−q·W) predicts 0.908, measured 0.888, because after seven losses (−$3,175) the eighth $3,200 bet does not fit the remaining $1,825 and is cut. A 7-loss stop (maxSteps 7, onCap stop): q = (19/37)^7 = 0.0094, (1 − q)^20 = 0.828, measured 0.830, CVaR 5 % −$3,119, bust 0.

P(win) ≈ (1 − q)^W
c9 at W = 20: (1 − 0.00356)^20 = 0.931
median = target while q·W < ln 2

Open this chapter in spinner, with the interactive charts