We study whether outcome bias persists in markets with actors who are financially incentivized to make optimal decisions. We test whether inherently noisy match outcomes from European football are correctly incorporated into prices from a betting exchange market. We find that market prices overestimate (underestimate) the winning probability of teams that previously overperformed (underperformed) in terms of match outcomes compared to their performance based on “expected goals.” This pattern is mirrored in negative (positive) betting returns on overperforming (underperforming) teams. These results suggest that even competitive market mechanisms fail to completely erase outcome bias.

中文翻译：

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当排行榜撒谎时：结果偏差是否会导致市场信息效率低下？


我们研究了在经济激励下做出最佳决策的参与者的市场中，结果偏差是否持续存在。我们测试欧洲足球固有的嘈杂比赛结果是否正确地纳入博彩交易市场的价格中。我们发现，与基于“预期进球”的表现相比，市场价格高估了（低估）了之前在比赛结果方面表现出色（表现不佳）的球队的获胜概率。这种模式反映在表现优异（表现不佳）球队的负（正）投注回报中。这些结果表明，即使是竞争性市场机制也无法完全消除结果偏差。