Idea Ripper // ArchiveCards: 1555 [Live] | Updated: 2026-10-14
Card #c1289IR // #c1289Synthesis

"The simple definition of an ergodic system is one where the expected value of an activity performed by a group is the same for an individual carrying out the same activity over time." "Nobody would choose to play this game 100 times in a row because the expected outcome is almost certain death."

— In our words · Source: Trade Outside the Box (Brent Donnelly)

[Use when]

A bet looks good on average and you'll be making it over and over with the same bankroll.

[Why it matters]

If 100 people play Russian roulette once for $10 million, the group's average is attractive. One person playing 100 times dies. Donnelly applies this to all-in betting: a positive average can still ruin the individual who repeats the bet.

More from Trade Outside the Box

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Same situation, different book

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