Does Concentration Matter? Measurement of Petroleum Merger Price Effects
研究了旧金山湾区两次炼油厂所有权变更对汽油价格的影响，检验市场集中度与价格的关系，未发现一致的证据。
We have estimated the price effects of two changes in market structure resulting from two changes in the ownership of gasoline refineries in the San Francisco Bay area: Tosco's purchase of Unocal's Rodeo refinery in April 1997 and UDS's purchase of Tosco's Avon refinery in August 2000. These events provide a relatively unique opportunity to test a price concentration relationship. If market concentration is related to price, then we should observe prices increase and then decrease by a similar amount following these transactions. We do not find evidence of a consistent price concentration relationship.