【主讲】俞宁 (斯坦福大学经济系博士候选人)
【主题】Carpe Diem, Carpe Worm: Context-Dependent Choice as Explained by Foraging Theory
【时间】2014年11月4日 (周二) 15：30-17：00
【地点】上海财经大学经济学院楼801室
【语言】英文
【摘要】Phenomena of context-dependent choice --- including decoy effects and choice overload --- though seemingly irrational and detrimental to fitness, have been observed across a wide range of species. We formulate a dynamic foraging choice model in which an organism is learning how favorable the environment is. It is shown that context effects can be results of a forager's rational inferences about the environment. For example, if the presence of a dominated prey indicates future low qualities of its kind, this presence bolsters the appeal --- or the decision value --- of a dominating prey in the current period. Our model lends support to a spectrum of psychological models, because the stylized choice procedures they suggest can be ecologically optimal for organisms facing dynamic foraging problems. With psychological models accounting for proximate causes of context effects, our suggestion of the ultimate cause can help disentangle the mystery of why natural selection fails to eliminate context effects. We also demonstrate the economic significance of the model by showing how online shoppers may behave similarly for good reason.
