Measurement Of Platforms' Market Share And Application

With the continuous development of network technologies and the increasing maturity of online payment technologies,the industry of two-sided platforms has developed rapidly,and the trend of high concentration has become more pronounced.Since 2015,there have been many cases of horizontal mergers between giants of two-sided platforms,such as 58.com and ganji.com,Ctrip.com and Qunar.com,meituan.com and dianping.com,Didi Chuxing and China Uber,etc.In the relevant markets,the emergence of a single or highly concentrated platform has caused public opinion to attach great importance,and it is particularly important for antitrust authorities to assess the combined market power.How to measure the combined market power is the core link in the antitrust review process.The availability of market share data and the ease of operation make it an important way to quantify market power.In the traditional one-sided market,the market share is measured by the proportion of the sales or sales volume of the manufacturers,and then the market power is measured.However,in the horizontal merger case applied to two-sided platforms,there are multiple alternative indicators for measuring market share.For example,in the case of horizontal mergers between trading platforms,there are data indicators of the ratio of platform trading volume and the proportion of both users to the three market shares.How to choose more reasonable indicators to measure market share and then measure the merger The market power will become an extra link in the antitrust investigation,will increase the unnecessary costs in the investigation process.This paper is in this context,to study the measurement of the market share of the two-sided platform.The paper aims to provide some theoretical support for the market share measurement of the antitrust investigation and reduce unnecessary costs.In the antitrust investigation,market share is an important way to measure the market power of the manufacturer,which is often used to determine whether the manufacturer has market power.Due to the existence of multi-party participants in the two-sided market,there are multiple alternative variables for measuring market share.This paper is divided into trading platforms and non-trading platforms to examine the choice of three alternative variables to measure market share:platform trading volume,side 1 user size,side 2 user size.Focusing on the basic meaning of market power,by building a platform competition model,it is found that the trading volume of the platform is not the direct source of the profit change,it is the change of the user scale on both sides that brings about the change of trading volume,which ultimately influences the profit level of the platform.Therefore,the trading volume is not suitable as an indicator for measuring market share,it merely reflects the profit levels.Excluding transaction volume as an alternative measure to measure market share,the comparative analysis of different types of platforms is obtained:the scale of users with strong cross-network externalities plays a significant role in the positive changes in platform profit,and it is the fundamental source of market power.Different user attributions do not affect the final research results.Therefore,the user scale proportion of the cross-network externalities is the best indicator to measure the market share of the two-sided platform.At the end of the paper,the cross-network externalities of the online car-hailing platform are measured by the attribution curve and simultaneous equations.The study finds that:in the online car-hailing platform,the cross-network externalities brought by the driver to the passengers are stronger than those brought by the passengers to the driver.Subsequently,the paper empirically obtained relevant data from DiDi:The driver share is the fundamental source of profits for DiDi platform,and it is the most crucial competitiveness to acquire and enhance market power in the online market.The theoretical conclusion of this paper is verified by using real data.Therefore,based on theoretical analysis and empirical test,the following conclusions are obtained:in the aspect of measuring market share in the antitrust investigation,the user share with strong cross-network externalities is a reasonable indicator to measure the market share of two-sided platforms,and can accurately measure the market power of two-sided platforms.At the end of the article,the optimal market share of the selected online car-hailing platform is applied to the market power evaluation of the DiDi Uber Merge Case.The study found that the combination of DiDi Uber makes the concentration rate of the online car market extremely high and drops The market power of the platform has been greatly enhanced after the merger,which has changed the competition conditions in the online car-hailing market.Finally,the paper proposes several antitrust policy recommendations:First,fully integrate the cross-network external characteristics to accurately define the relevant market.Second,in the antitrust investigation,clarify the strength of the platform's cross-network externalities and select appropriate indicators to measure market share.Third,consider market power based on market share and comprehensively consider other factors.Fourth,improve China's "Antitrust Law"review standards and set safe harbor rules.