Moving away from the effects-based approach in EU competition law, the Digital Markets Act introduces renewed requisite legal standards that differ from probabilistic standards of proof. Ideally, this concept should also shape the European Commission’s initial enforcement actions and its judicial review in the EU courts. The paper critically examines the legal standards that the European Commission established in its first set of designation decisions issued in September 2023. It spotlights two significant actions by the Commission: the delineation of core platform services and the consideration of the undertakings’ rebuttals of the presumption of a gatekeeper position deriving from the application of the quantitative thresholds. The paper reveals a disjointed approach by the Commission building upon the idea of the regulation’s plasticity.
{"title":"The Requisite Legal Standard of the Digital Markets Act’s Designation Process","authors":"Alba Ribera Martínez","doi":"10.1093/joclec/nhae011","DOIUrl":"https://doi.org/10.1093/joclec/nhae011","url":null,"abstract":"Moving away from the effects-based approach in EU competition law, the Digital Markets Act introduces renewed requisite legal standards that differ from probabilistic standards of proof. Ideally, this concept should also shape the European Commission’s initial enforcement actions and its judicial review in the EU courts. The paper critically examines the legal standards that the European Commission established in its first set of designation decisions issued in September 2023. It spotlights two significant actions by the Commission: the delineation of core platform services and the consideration of the undertakings’ rebuttals of the presumption of a gatekeeper position deriving from the application of the quantitative thresholds. The paper reveals a disjointed approach by the Commission building upon the idea of the regulation’s plasticity.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"178 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This comprehensive review of ex post merger studies assesses the price effects of horizontal transactions to determine whether there are common post-merger price effects, both overall and in specific markets. The aim is to derive implications for policy makers and competition authorities in terms of effective merger enforcement and competition policy. By combining and further analysing the results of 52 retrospective studies on 82 mergers or horizontal transactions, it can be shown that the sector in which the respective transaction takes place alone is not a strong indicator of the direction of price-related merger effects. In contrast, the ‘size’ or ‘importance’ of a transaction as well as market concentration seem to be correlated with post-transaction price increases, especially in already highly concentrated markets. Overall, this meta-study shows the importance of ex post case studies for improving ex ante merger control: although generalizations can only be made with caution, the subsequent analysis of a case and its ex post observable outcome can provide useful information for future merger enforcement in general, either in the same industry and/or with similar case characteristics, as well as for competition policy regulators.
{"title":"Price Effects of Horizontal Mergers: A Retrospective on Retrospectives","authors":"Annika Stöhr","doi":"10.1093/joclec/nhae006","DOIUrl":"https://doi.org/10.1093/joclec/nhae006","url":null,"abstract":"This comprehensive review of ex post merger studies assesses the price effects of horizontal transactions to determine whether there are common post-merger price effects, both overall and in specific markets. The aim is to derive implications for policy makers and competition authorities in terms of effective merger enforcement and competition policy. By combining and further analysing the results of 52 retrospective studies on 82 mergers or horizontal transactions, it can be shown that the sector in which the respective transaction takes place alone is not a strong indicator of the direction of price-related merger effects. In contrast, the ‘size’ or ‘importance’ of a transaction as well as market concentration seem to be correlated with post-transaction price increases, especially in already highly concentrated markets. Overall, this meta-study shows the importance of ex post case studies for improving ex ante merger control: although generalizations can only be made with caution, the subsequent analysis of a case and its ex post observable outcome can provide useful information for future merger enforcement in general, either in the same industry and/or with similar case characteristics, as well as for competition policy regulators.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"32 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The European Commission (EC) has recently announced its intention to issue Guidelines on exclusionary abuses. In this paper, we explain how economics can and should be used to inform a sound and effects-based approach in the enforcement of Article 102 TFEU. In particular, the EC should be guided only by a consumer welfare standard; exclusive dealing and exclusivity rebates should be subject to a (rebuttable) presumption of harm; price–cost tests are meaningful only for predation and other practices that do not reference rivals; essentiality of the input should not be a requirement for vertical foreclosure cases of any type, but such cases should be limited only to dominant firms that satisfy certain criteria.
{"title":"ECONOMIC PRINCIPLES FOR THE ENFORCEMENT OF ABUSE OF DOMINANCE PROVISIONS","authors":"Chiara Fumagalli, Massimo Motta","doi":"10.1093/joclec/nhae003","DOIUrl":"https://doi.org/10.1093/joclec/nhae003","url":null,"abstract":"The European Commission (EC) has recently announced its intention to issue Guidelines on exclusionary abuses. In this paper, we explain how economics can and should be used to inform a sound and effects-based approach in the enforcement of Article 102 TFEU. In particular, the EC should be guided only by a consumer welfare standard; exclusive dealing and exclusivity rebates should be subject to a (rebuttable) presumption of harm; price–cost tests are meaningful only for predation and other practices that do not reference rivals; essentiality of the input should not be a requirement for vertical foreclosure cases of any type, but such cases should be limited only to dominant firms that satisfy certain criteria.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"160 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140202508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We argue that mergers among market laggards (new entrants or innovation challengers) should be treated differently than those involving leaders (established players or first-mover innovators). We show that these mergers can be rivalry-enhancing, either by accelerating entry or promoting innovations, leading to lower quality-adjusted prices and higher consumer surplus. This is more likely to happen when entry (or innovation) costs are relatively high, so that entry (or innovation) is profitable only when it is limited to a few players. In these circumstances, if laggards enter, they will do so probabilistically and inefficiently since each of them would have to condition its entry to scenarios in which other laggards stay out, which may not be possible since entry decisions are secret. By removing or mitigating this coordination failure, a merger among laggards may lead to more entry (or innovation). Such a merger will also be more likely to benefit consumers when the products of laggards and leaders are sufficiently differentiated—that is, when competition is not too intense absent the merger. Importantly, we find that in the presence of fixed entry costs and endogenous entry, fixed cost synergies are relevant for assessing the welfare effects of mergers. These efficiencies enhance the social value of mergers among laggards insofar as they make entry into the market for the merged entity less costly, thereby expanding the spectrum of products available to consumer and increasing their welfare.
{"title":"MERGING LAGGARDS","authors":"Jorge Padilla, Salvatore Piccolo, Paul Reynolds","doi":"10.1093/joclec/nhad020","DOIUrl":"https://doi.org/10.1093/joclec/nhad020","url":null,"abstract":"We argue that mergers among market laggards (new entrants or innovation challengers) should be treated differently than those involving leaders (established players or first-mover innovators). We show that these mergers can be rivalry-enhancing, either by accelerating entry or promoting innovations, leading to lower quality-adjusted prices and higher consumer surplus. This is more likely to happen when entry (or innovation) costs are relatively high, so that entry (or innovation) is profitable only when it is limited to a few players. In these circumstances, if laggards enter, they will do so probabilistically and inefficiently since each of them would have to condition its entry to scenarios in which other laggards stay out, which may not be possible since entry decisions are secret. By removing or mitigating this coordination failure, a merger among laggards may lead to more entry (or innovation). Such a merger will also be more likely to benefit consumers when the products of laggards and leaders are sufficiently differentiated—that is, when competition is not too intense absent the merger. Importantly, we find that in the presence of fixed entry costs and endogenous entry, fixed cost synergies are relevant for assessing the welfare effects of mergers. These efficiencies enhance the social value of mergers among laggards insofar as they make entry into the market for the merged entity less costly, thereby expanding the spectrum of products available to consumer and increasing their welfare.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"168 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139580409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amelia Fletcher, Jacques Crémer, Paul Heidhues, Gene Kimmelman, Giorgio Monti, Rupprecht Podszun, Monika Schnitzer, Fiona Scott Morton, Alexandre de Streel
Economic thinking and analysis lie at the heart of the objectives and the design of the EU Digital Markets Act (DMA). However, the design of the DMA reflects a very deliberate—and reasonable—intention to ensure clarity, speed, administrability, and enforceability. In doing so, this pro-competitive regulation omits several elements of standard competition law where economics has typically played a key role. Nonetheless, we believe that economic insights and analysis—including behavioural economic thinking—will continue to play an important role in enabling the DMA to achieve its ambitious and laudable goals, albeit in a somewhat different way.
{"title":"The Effective Use of Economics in the EU Digital Markets Act","authors":"Amelia Fletcher, Jacques Crémer, Paul Heidhues, Gene Kimmelman, Giorgio Monti, Rupprecht Podszun, Monika Schnitzer, Fiona Scott Morton, Alexandre de Streel","doi":"10.1093/joclec/nhad018","DOIUrl":"https://doi.org/10.1093/joclec/nhad018","url":null,"abstract":"Economic thinking and analysis lie at the heart of the objectives and the design of the EU Digital Markets Act (DMA). However, the design of the DMA reflects a very deliberate—and reasonable—intention to ensure clarity, speed, administrability, and enforceability. In doing so, this pro-competitive regulation omits several elements of standard competition law where economics has typically played a key role. Nonetheless, we believe that economic insights and analysis—including behavioural economic thinking—will continue to play an important role in enabling the DMA to achieve its ambitious and laudable goals, albeit in a somewhat different way.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"57 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There are well-documented episodes of prices remaining at supracompetitive levels even after a cartel was shut down by the competition authority. As long as market conditions remain reasonably stable, collusive prices may still be incentive compatible so the collusive equilibrium could continue after firms are no longer engaging in illicit communications. This situation poses a challenging dilemma: consumer harm persists because of past unlawful conduct but there is no apparent recourse. This paper offers a remedy in the form of coupons. As part of the penalty imposed by the competition authority, each cartel member is required to distribute coupons to its past purchasers. Contrary to their usual form, these coupons can only be used to buy from a firm’s competitors. I show how this temporary intervention can help destabilize collusion and restore competition.
{"title":"Competitor Coupons: A Remedy for Residual Collusion","authors":"Joseph E Harrington","doi":"10.1093/joclec/nhad019","DOIUrl":"https://doi.org/10.1093/joclec/nhad019","url":null,"abstract":"There are well-documented episodes of prices remaining at supracompetitive levels even after a cartel was shut down by the competition authority. As long as market conditions remain reasonably stable, collusive prices may still be incentive compatible so the collusive equilibrium could continue after firms are no longer engaging in illicit communications. This situation poses a challenging dilemma: consumer harm persists because of past unlawful conduct but there is no apparent recourse. This paper offers a remedy in the form of coupons. As part of the penalty imposed by the competition authority, each cartel member is required to distribute coupons to its past purchasers. Contrary to their usual form, these coupons can only be used to buy from a firm’s competitors. I show how this temporary intervention can help destabilize collusion and restore competition.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"32 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139054247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study innovation incentives under “product hopping,” whereby an incumbent patents a minor modification of a pioneer drug (for example, a new delivery method) and promotes the modified version to shift demand from the original drug. We develop a model in which an incumbent races against an entrant to discover a drastic innovation. We show that product hopping can decrease the total research and development (R&D) investment for drastic innovation. Moreover, an incumbent only chooses to engage in product hopping when drastic innovation is sufficiently difficult. Although product hopping may boost ex-ante R&D for pioneer drugs, it comes at the expense of decreasing R&D for subsequent drastic innovations and consumer surplus through socially wasteful marketing expenses. Our results contribute to the policy debate on product hopping, welfare, and antitrust.
{"title":"Product Hopping and Innovation Incentives","authors":"Jorge Lemus, Olgu Ozkul","doi":"10.1093/joclec/nhad017","DOIUrl":"https://doi.org/10.1093/joclec/nhad017","url":null,"abstract":"We study innovation incentives under “product hopping,” whereby an incumbent patents a minor modification of a pioneer drug (for example, a new delivery method) and promotes the modified version to shift demand from the original drug. We develop a model in which an incumbent races against an entrant to discover a drastic innovation. We show that product hopping can decrease the total research and development (R&D) investment for drastic innovation. Moreover, an incumbent only chooses to engage in product hopping when drastic innovation is sufficiently difficult. Although product hopping may boost ex-ante R&D for pioneer drugs, it comes at the expense of decreasing R&D for subsequent drastic innovations and consumer surplus through socially wasteful marketing expenses. Our results contribute to the policy debate on product hopping, welfare, and antitrust.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"60 4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138563197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We lay out a roadmap for how the legislator could create a framework of ‘sustainability corridors’ that would allow relying on the ancillary restraints/Wouters doctrine to make antitrust law more accommodating of sustainability considerations. Our analysis goes beyond the general feasibility of such corridors. It discusses different use-cases for such exemptions and methods for assessing the necessity of competitive restraints to achieve a legislatively defined sustainability goal. We show how this avoids the pitfalls of a multigoals approach, under which it would be left to antitrust authorities and courts to reconcile sustainability and competition objectives independent of a legislative specification, whereas out-of-market benefits (externalities) that would escape even a broad consumer welfare approach can still be accounted for. Our proposal sets out specific requirements for such sustainability corridors that ensure that the ensuing antitrust assessment is governed by a strict and quantifiable indispensability test. Specifically, we discuss three such instances: specific sustainability obligations placed on individual firms, which may however require collective actions; specific mandates that are targeted at the respective industry rather than individual firms; and policy objectives that are not targeted at individual firms or industries but provide a metric for the measurement of sustainability benefits (for example, by way of conducting an abatement cost analysis).
{"title":"Legal Design in Sustainable Antitrust","authors":"Roman Inderst, Stefan Thomas","doi":"10.1093/joclec/nhad016","DOIUrl":"https://doi.org/10.1093/joclec/nhad016","url":null,"abstract":"We lay out a roadmap for how the legislator could create a framework of ‘sustainability corridors’ that would allow relying on the ancillary restraints/Wouters doctrine to make antitrust law more accommodating of sustainability considerations. Our analysis goes beyond the general feasibility of such corridors. It discusses different use-cases for such exemptions and methods for assessing the necessity of competitive restraints to achieve a legislatively defined sustainability goal. We show how this avoids the pitfalls of a multigoals approach, under which it would be left to antitrust authorities and courts to reconcile sustainability and competition objectives independent of a legislative specification, whereas out-of-market benefits (externalities) that would escape even a broad consumer welfare approach can still be accounted for. Our proposal sets out specific requirements for such sustainability corridors that ensure that the ensuing antitrust assessment is governed by a strict and quantifiable indispensability test. Specifically, we discuss three such instances: specific sustainability obligations placed on individual firms, which may however require collective actions; specific mandates that are targeted at the respective industry rather than individual firms; and policy objectives that are not targeted at individual firms or industries but provide a metric for the measurement of sustainability benefits (for example, by way of conducting an abatement cost analysis).","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"27 7","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138513976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract At which stage in the production chain should patent licensing take place? In this paper we show that under realistic circumstances a patent holder would be better off by licensing downstream. This occurs when the licensing revenue can depend on the downstream value of the product either directly or through the use of ad-valorem royalties. Downstream licensing is also preferred by the patent holder when, instead, we assume that the downstream licensee is less informed about the validity of the patent. In most cases, downstream licensing increases allocative efficiency. However, it might reduce the manufacturer’s incentives to invest and, thereby, decrease welfare. We characterize the circumstances under which a conflict arises between the stage at which patent holders prefer to license their technology and the stage at which it is optimal from a social standpoint that licensing takes place.
{"title":"INVESTMENT AND PATENT LICENSING IN THE VALUE CHAIN","authors":"Gerard Llobet, Damien Neven","doi":"10.1093/joclec/nhad015","DOIUrl":"https://doi.org/10.1093/joclec/nhad015","url":null,"abstract":"Abstract At which stage in the production chain should patent licensing take place? In this paper we show that under realistic circumstances a patent holder would be better off by licensing downstream. This occurs when the licensing revenue can depend on the downstream value of the product either directly or through the use of ad-valorem royalties. Downstream licensing is also preferred by the patent holder when, instead, we assume that the downstream licensee is less informed about the validity of the patent. In most cases, downstream licensing increases allocative efficiency. However, it might reduce the manufacturer’s incentives to invest and, thereby, decrease welfare. We characterize the circumstances under which a conflict arises between the stage at which patent holders prefer to license their technology and the stage at which it is optimal from a social standpoint that licensing takes place.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"35 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135430307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joanna Piechucka, Lluís Saurí-Romero, Ben Smulders
Abstract This paper contributes to the current debate on industrial policies, by discussing the potential scope and design principles of efficiency-enhancing industrial policies and providing a framework of assessment based on the European experience with State aid control. It argues four main points. First, there is scope for efficiency-enhancing industrial policies that address well-defined market failures. Second, the design of any industrial policy must achieve its objective in the most efficient way possible, in particular avoiding unnecessary distortions to competition. Third, European Union (EU) State aid control rules, as part of competition policy, reflect the economic principles of efficiency-enhancing industrial policies and provide a blueprint that could be applied more broadly to improve the design of industrial policies. Fourth, the pressure from industrial policies of non-EU governments comes with risks of global subsidy races that would produce a suboptimal outcome for all. Some limiting principles must therefore be found. We then illustrate how State aid control can contribute to a more efficient design of climate and industrial policies, contributing to a more efficient green transition, preserving competitive markets, and fostering industrial competitiveness.
{"title":"Industrial Policies, Competition, and Efficiency: The Need for State Aid Control","authors":"Joanna Piechucka, Lluís Saurí-Romero, Ben Smulders","doi":"10.1093/joclec/nhad014","DOIUrl":"https://doi.org/10.1093/joclec/nhad014","url":null,"abstract":"Abstract This paper contributes to the current debate on industrial policies, by discussing the potential scope and design principles of efficiency-enhancing industrial policies and providing a framework of assessment based on the European experience with State aid control. It argues four main points. First, there is scope for efficiency-enhancing industrial policies that address well-defined market failures. Second, the design of any industrial policy must achieve its objective in the most efficient way possible, in particular avoiding unnecessary distortions to competition. Third, European Union (EU) State aid control rules, as part of competition policy, reflect the economic principles of efficiency-enhancing industrial policies and provide a blueprint that could be applied more broadly to improve the design of industrial policies. Fourth, the pressure from industrial policies of non-EU governments comes with risks of global subsidy races that would produce a suboptimal outcome for all. Some limiting principles must therefore be found. We then illustrate how State aid control can contribute to a more efficient design of climate and industrial policies, contributing to a more efficient green transition, preserving competitive markets, and fostering industrial competitiveness.","PeriodicalId":45547,"journal":{"name":"Journal of Competition Law & Economics","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135976782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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