The process of removing the bookmaker's margin from odds to estimate the true probability of each outcome.
De-vigging (or de-juicing) is the mathematical process of removing the bookmaker's margin from odds to estimate true, fair probabilities. Since bookmaker odds include vig, they overstate the probability of all outcomes.
There are multiple de-vig methods, each with different assumptions: - Multiplicative: scales all probabilities proportionally - Additive: subtracts equal margin from each side - Power: uses exponential scaling (favors longshots less) - Shin: models the impact of insider trading - Logarithmic: entropy-based approach
The choice of method matters most in lopsided markets. For -110/-110, all methods give approximately 50/50.
The bookmaker's built-in commission. The difference between true odds and what you're offered.
True ProbabilityThe actual estimated likelihood of an outcome, with the bookmaker's margin removed.
OverroundThe total implied probability exceeding 100% across all outcomes in a market — the bookmaker's total margin.
Implied ProbabilityThe probability of an outcome implied by the odds. Includes the bookmaker's margin (vig).