Econ Papers Daily / 期刊论文
注意力不集中、信息提供与（显示性偏好的）失灵
Inattention, Information Provision, and (Failures of) Revealed Preference,
摘要
Economists often estimate preferences by looking at how demand for an option changes as its attributes change or as beliefs about them change in response to information. I show in a multi-attribute induced-preference experiment that this method can be substantially biased due to differential inattention. Attention is systematically distorted at baseline, with participants reacting much more to some attributes than others. Further, attention is highly malleable: information telling participants about the value of a desirable attribute—even when the information is already known, transparently redundant, and explicitly randomly assigned—greatly increases attention to the attribute it describes and distracts from other attributes. It also boosts average demand for the good, implying that inattention takes the form of neglect rather than shrinkage toward a prior. These results combine to imply that information experiments with passive control groups can be greatly misleading about preferences and can even have the wrong sign: in my experiment, reducing overoptimism about an attribute nonetheless boosts demand for its associated good. I show, both theoretically and experimentally, that active control-group experiments yield preference estimates with the correct sign but biased magnitudes. Finally I show that parallel active control-group experiments (PACEs) can solve this problem: PACEs yield unbiased estimates of preferences under an equal induced-attention assumption, which is testable (and satisfied) in my experiment.
中文摘要
经济学家通常通过观察某一选项的需求如何随其属性变化，或随关于这些属性的信念因信息而变化来估计偏好。我在一个多属性诱导偏好实验中表明，由于差异性不注意，这种方法可能严重偏误。基线状态下注意被系统性扭曲，参与者对某些属性的反应远强于其他属性。此外，注意具有高度可塑性：告知参与者某一合意属性价值的信息——即使该信息已为人知、明显冗余且被明确随机分配——也会大幅增加对其所描述属性的注意，并分散对其他属性的注意。它还会提高对该商品的总体需求，这意味着不注意表现为忽视，而非向先验收缩。这些结果共同表明，带有被动控制组的信息实验可能严重误导对偏好的判断，甚至可能符号相反：在我的实验中，降低对某一属性的过度乐观反而提高了对相关商品的需求。我从理论和实验两方面表明，主动控制组实验产生的偏好估计符号正确，但幅度有偏。最后，我表明平行主动控制组实验（PACEs）可以解决这一问题：在同等诱导注意假设下，PACEs产生无偏的偏好估计，而该假设在我的实验中是可检验的（且得到满足）。