Vig
Vig is the built-in margin in quoted prices. In prediction-style products it often shows up through spread, fees, or pricing skew.
Definition
Vig is a term from betting that describes built-in margin. In exchange-style prediction markets, margin is less about a fixed vig and more about trading frictions like bid ask spread and trading fee.
Why it matters
Users often assume prices are fair. In practice, costs and frictions mean you need a stronger edge to overcome the effective margin of the market.
Common pitfalls
Comparing spreads and calling it vig: Spread is an execution friction, not always a fixed margin.
Ignoring fees: Fees can be the dominant margin in bounded price markets.