efficient market hypothesis

The theory that asset prices reflect all available information, making it impossible to consistently earn excess returns. In prediction markets, this manifests as prices quickly incorporating new information, leaving few systematic edges.

Cluster: Information Theory

Related Concepts

• wisdom of crowds — The phenomenon where aggregated group estimates often outperform individual experts in forecasting accuracy.
• sports betting — Wagering on the outcome of sporting events, one of the oldest and largest prediction markets. Its odds aggregation and pricing dynamics offer lessons for how event markets handle information, liquidity, and crowd behavior.
• parimutuel markets — A betting structure where all wagers pool together and payouts are split proportionally among winners after the event resolves. Parimutuel markets bootstrap liquidity without market makers, making them useful for niche or long-tail prediction markets, but face challenges around locked positions, timing, and real-time price readability.
• information aggregation — The process by which markets combine dispersed private knowledge into a single consensus price signal.

Articles about efficient market hypothesis

• The Wisdom of Crowds in Markets: Crowd Behavior in Prediction, Betting, and Stock Markets by Michael Mauboussin, Dan Callahan