Glossary/Implied probability
Implied probability
Implied probability is the market’s price-implied chance that an event occurs. On binary prediction markets, the mid (or last trade) of a Yes/Up token is often treated as a probability — before fees, risk premia, and liquidity adjustments.
How AymarData records it
For Polymarket and Kalshi books, derive implied probability from mid or microprice on the relevant outcome token returned by /v1/book. Do not assume Up + Down mids sum exactly to 1 after costs. See prediction-market and binary-option terms.