To study coordination in complex social systems such as financial markets, the authors introduce a new prediction market set-up that accounts for fundamental uncertainty. Nonetheless, the market is designed so that its total value is known, and thus its rationality can be evaluated. In two...

The favorite-longshot bias describes the longstanding empirical regularity that betting odds provide biased estimates of the probability of a horse winning - longshots are overbet, while favorites are underbet. Neoclassical explanations of this phenomenon focus on rational gamblers who overbet...

If betting markets are efficient, then the expected loss rate on all bets on a game can be calculated from the quoted odds. Guides to sports betting tell bettors how to do this calculation of the predicted average loss rate. We show that if bookmakers set higher profit margins for bets with...

Online sports betting is growing rapidly around the world. We describe how the competitive structure of the bookmaking market affects odds when bettors disagree about the probabilities of the outcomes of sporting events but are on average correct. We show that the demand for bets on longshots is...

Research on sports betting markets has generally found a favorite-longshot bias, the empirical pattern for loss rates for bets on longshots to be higher than for favorites, which implies the odds do not reflect the underlying probabilities. The existing literature focuses largely on pari-mutuel...

The CFTC has recently licensed a commercial prediction market to operate in the US. Previous theoretical work has not incorporated that prediction markets charge fees. We examine the impact of fees by introducing them to a model in which the market price equals the true probability when there...

Sports betting markets can be considered strongly efficient if expected returns on all possible bets on an event are equal. If this form of efficiency holds, then there is a direct mapping from betting odds into probabilities of outcomes of sporting events. We compare two regression-based...