This paper examines inefficiencies related to moneyline movement that were recently revealed for Major League Baseball (MLB) games and explores the extent to which they can be generalized to markets for other sports. Behavior of National Football League (NFL), National Basketball Association (NBA), and National Hockey League (NHL) pre-game betting markets is analyzed from opening until closing using detailed moneyline movement at three sportsbooks from 2019 to 2023. Price changes in these markets exhibit significant negative autocorrelation in each sport, suggesting that overreaction of sportsbooks is a broad characteristic of sports betting markets. A weekend effect similar to that observed in MLB arises for NBA games as well; market performance in the hours leading up to a game improves significantly more on weekdays than on weekends. Little evidence is found to suggest unreliability of individual prices; moneylines for NFL, NBA, and NHL games appear to be mostly accurate.
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