Information Acquisition and Efficient Mechanism Design
研究在代理人可秘密获取信息后参与机制时，是否存在能同时实现事前和事后效率的机制。发现私有价值下VCG机制可行，共同价值下通常不可调和，并给出子模和超模条件。
We consider a general mechanism design setting where each agent can acquire (covert) information before participating in the mechanism. The central question is whether a mechanism exists that provides the efficient incentives for information acquisition ex-ante and implements the efficient allocation conditional on the private information ex-post.<br/>It is shown that in every private value environment the Vickrey-Clark-Groves mechanism guarantees both ex-ante as well as ex-post efficiency. In contrast, with common values, ex-ante and ex-post efficiency cannot be reconciled in general. Sufficient conditions in terms of sub- and supermodularity are provided when (all) ex-post efficient mechanisms lead to private under- or over-acquisition of information.