从市场势力到有效市场势力--以中国化学药品制剂制造业为例

企业层面市场势力及其福利损失的准确估计是产业组织领域的基础性研究问题,厘清市场份额、市场势力及福利损失的相互关系有助于为反垄断政策的制定提供参考并帮助企业决策。本文定义"有效市场势力"为企业销售额所占市场份额和Lerner指数的乘积,并证实在给定的垄断竞争行业中有效市场势力与福利损失存在近似线性关系,因此从福利分析的角度,有效市场势力比市场势力更需要被重视。通过理论分析,本文给出了企业层面市场势力和福利损失的估计方法,修正了以产出价值量代替实物量进行生产函数估计时存在的偏误。通过实证分析,本文将相关方法应用于中国化学药品制剂制造业研究,发现1999~2015年中国上市化药企业平均市场势力为0.149,未表现出太强的垄断性;样本期间每家上市化药企业每年平均福利损失为0.76亿元,约占营业收入的7%;政府规制对化药企业市场势力和有效市场势力具有一定的影响,但近年来该影响趋于稳定,因此放弃直接的药品价格规制转而依靠药品价格谈判机制和反垄断规制不会对化学药品制剂市场产生剧烈影响。

From Market Power to Effective Market Power:An Example of Chinese Pharmaceutical Industry

The accurate estimation of market power and welfare loss at the enterprise level is a basic research problem inthe field of industrial organization.Clarifying the relationship between market share,market power and welfare loss isbenefit to provide references for the formulation of antitrust policy and help enterprises make right decisions.This pa+per defines"effective market power"as the product of the market share of enterprise sales and Lerner Index,andproves that there is an approximate linear relationship between effective market power and welfare loss in a given mo-nopoly and competitive industry.Therefore,from the perspective of welfare analysis,effective market power needs tobe paid more attention than market power.Through theoretical analysis,this paper gives the estimation method of mar-ket power and welfare loss at the enterprise level,corrects the errors in the estimation of production function by usingoutput value instead of physical quantity.Through empirical analysis,this paper applies the relevant methods to thestudy of China's pharmaceutical industry.It is found that the average market power of China's listed pharmaccuticalenterprises from 1999 to 2015 was 0.149,which did not show too strong monopoly;the average annual welfare loss ofeach enterprise was 76 million Yuan,accounting for about 7%of the operating revenue;Government regulations have certain impacts on the market power and effective market power of chemical manufacturing enterprises,but the im-pacts are stabilized in recent years.Therefore,abandoning direct price regulation and relying on price negotiationmechanism and antitrust regulation will not have strong impacts on the pharmaceutical market.