Lesson 3 · Foundations · 18 min
Variance and Bankroll
Why a bankroll is a statistical instrument, and how to size yours like a practitioner.
Variance is the reason a session feels nothing like its expected value. A single 35:1 hit can wipe out a long losing streak; a long losing streak can wipe out a surprisingly respectable bankroll. Neither proves anything about the wheel.
A practical bankroll is designed to survive a reasonable negative run. Most seasoned players plan for sessions of N chips where N is at least 40–60x their base bet for outside bets, and 200x for straight-ups. The exact numbers are less important than the discipline of planning before sitting.
Key takeaways
- Variance is not streakiness — it is finite-sample fluctuation.
- Bankroll size should match bet type and session length.
- Plan bankrolls before the session; never mid-session.