Build intuition about compounding and decay.
Each round pick the better of two bets. The right answer is the one with the higher expected log return E[log r] — the geometric growth rate that governs what actually happens to wealth compounded over time, as opposed to the arithmetic mean which can look good on average while being ruinous for any individual path.
This is the core of Ergodicity Economics (Ole Peters, London Mathematical Laboratory / Santa Fe Institute): maximise time-average growth, not ensemble-average return.
Long/short mode: picking A means long A, short B — P&L is the spread. Green = always optimal, red = always worst, blue = you. All three share the same random draws so the gap is pure decision quality.
Press H to toggle hints showing E[log r] for each option.