We introduce a set-valued solution concept, M equilibrium, to capture empirical regularities from over half a century of game theory experiments. We show M equilibrium serves as a meta theory for various models that hitherto were considered unrelated. M equilibrium is empirically robust and, despite being set-valued, falsifiable. Results from a series of experiments that compare M equilibrium to leading behavioral game theory models demonstrate its virtues in predicting observed choices and stated beliefs. Data from experimental games with a unique pure-strategy Nash equilibrium and multiple M equilibria exhibit coordination problems that could not be anticipated through the lens of existing models. (JEL C72, C90, D83)

中文翻译：

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M 均衡：游戏中的信念和选择理论

我们引入了一个集值解决方案概念，M 均衡，以从半个多世纪的博弈论实验中捕捉经验规律。我们展示了 M 平衡作为迄今为止被认为不相关的各种模型的元理论。M 均衡在经验上是稳健的，尽管是设定值的，但可以证伪。将 M 均衡与领先的行为博弈论模型进行比较的一系列实验结果证明了它在预测观察到的选择和陈述的信念方面的优点。来自具有独特纯策略纳什均衡和多个 M 均衡的实验博弈的数据显示出无法通过现有模型的镜头预期的协调问题。(JEL C72, C90, D83)