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Part III: Business & Regulation · Gambling Mathematics & Probability

1. Probability

Foundational Probability

Probability is the mathematical measure of the likelihood that a specific event will occur, expressed as a ratio of favorable outcomes to all possible outcomes. In casino gaming, probability forms the foundation of every game design decision, determining payout ratios, house edge calculations, and expected value. For example, the probability of rolling a 7 with two six-sided dice is 6/36 = 16.67%, since there are six combinations that produce a 7 out of 36 total possible outcomes. Casino surveillance professionals use probability to identify statistically anomalous events that may indicate cheating or game integrity issues.

In practice

Probability ranges from 0 (impossible event) to 1 (certain event). In games with replacement (like roulette), probabilities remain constant on each trial; in games without replacement (like blackjack), probabilities change as cards are removed from play.

Related terms

More in Foundational Probability

2. Odds·3. True Odds·4. Payout Odds·8. Variance·9. Standard Deviation·12. Hit Frequency·14. Independent Events·15. Dependent Events

One entry from the Casino Industry Glossary — 1,157 terms written for surveillance, compliance and operations professionals rather than for players. Definitions describe industry usage; where a term carries a regulatory meaning, verify against the instrument that governs your jurisdiction.