Conspiracy at the Pump
基于价格操纵证据，加拿大竞争局于2006年对魁北克部分地区的零售加油站展开调查。本文使用双重差分法发现，调查公告后目标市场汽油价格每升下降1.75加分，并检验了斯蒂格勒合谋理论在现实中的适用性。
On the basis of evidence of price‐fixing, in May 2006 the Canadian Competition Bureau targeted retail gasoline outlets in some local markets in the province of Quebec. In June 2008, criminal charges were filed against many individuals and companies operating in those local markets. We employ a differences‐in‐differences approach to determine whether the public announcement of the antitrust investigation triggered a reaction in one of the targeted markets. We find that the price of gasoline in the targeted market fell by 1.75 cents per liter after the public announcement of the investigation. We also briefly discuss how well the Stiglerian theory of collusion performs in this real‐world conspiracy.