Expected Value & the Bets Behind Trading

The one idea that underpins every good trading decision.

Inside this lesson

Compute the expected value of a simple bet from its possible outcomes and probabilities
Explain why a positive-EV decision can still lose in any one instance
Distinguish a 'good decision' from a 'good outcome'
Explain what variance adds when comparing two bets that share the same expected value

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⚖️

Educational content only — not financial, investment, trading, tax, or legal advice, and not an inducement to buy or sell anything. Examples and figures are illustrative, use hypothetical data, and are not predictions. Independent educational material; third-party names are used descriptively and imply no affiliation.