We revisit the canonical binary-state model of social learning to investigate the possibility of non-monotone learning: ceteris paribus, with some predecessor(s) switching to actions that reveal greater confidence in one state of the world, agents nevertheless become more confident in the other. A necessary and sufficient condition for non-monotone learning is provided in an illustrative setting where agents are either uninformed or partially informed by binary private signals. In a general setting with continuous private signals, we obtain a sufficient condition for non-monotone learning that does not rely on the shape of the underlying information structures apart from a couple of simple boundary requirements. As a result, a social learning process that completes eventually can be well approximated in a way such that non-monotone learning and anti-imitation are bound to happen.

我们重新审视社会学习的标准二元状态模型，以研究非单调学习的可能性：ceteris paribus，随着某些前任采取行动以显示对世界一种状态的更大信心，行动者仍然对另一种状态变得更加自信。在说明性环境中提供了非单调学习的必要和充分条件，在这种情况下，代理不知情或部分被二进制私有信号告知。在具有连续私人信号的一般设置中，我们获得了非单调学习的充分条件，该条件不依赖于基础信息结构的形状，而没有几个简单的边界要求。结果，最终完成的社会学习过程可以以一定方式近似实现，从而必然会发生非单调学习和反模仿。