Part III: Business & Regulation · Gambling Mathematics & Probability

27. Betting Correlation (BC)

Blackjack Math

Betting correlation is a statistical measure (ranging from 0 to 1) of how effectively a card counting system identifies favorable betting situations — that is, how well the count correlates with the player’s actual mathematical advantage. A higher betting correlation means the count is a more accurate predictor of when the player should bet more or less. The Hi-Lo system has a betting correlation of 0.97, which is excellent. More complex systems like the Revere Point Count achieve BC values closer to 0.99, but the practical difference in profitability is minimal. Casino surveillance does not need to identify which specific system a player is using, but understanding that different systems exist helps explain variations in observed counting behavior.

In practice

BC measures correlation with the overall expectation change. Systems with high BC are most effective for bet sizing. A side count of aces can improve BC significantly because aces have a unique impact on blackjack probability.

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.