We use Uber fare data for passenger trips from Los Angeles, New York, and San Francisco airports to hotels in those metropolitan areas to test whether Uber engages in third-degree price discrimination by charging higher fares to travelers who originate from the same airports as other travelers but who stay at more expensive hotels. We find that fares are positively and statistically significantly related to the price of hotel rooms. Importantly, we also find that allowing ride-sharing companies to price discriminate improves travelers’ welfare, on average, by increasing their travel options.
{"title":"Does Uber Benefit Travelers by Price Discrimination?","authors":"Yen-Ling Chang, C. Winston, Jia Yan","doi":"10.1086/721266","DOIUrl":"https://doi.org/10.1086/721266","url":null,"abstract":"We use Uber fare data for passenger trips from Los Angeles, New York, and San Francisco airports to hotels in those metropolitan areas to test whether Uber engages in third-degree price discrimination by charging higher fares to travelers who originate from the same airports as other travelers but who stay at more expensive hotels. We find that fares are positively and statistically significantly related to the price of hotel rooms. Importantly, we also find that allowing ride-sharing companies to price discriminate improves travelers’ welfare, on average, by increasing their travel options.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"1991 1","pages":"S433 - S459"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82349015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper describes how ordinary citizens view economic regulation and summarizes answers to questions about regulation and regulators since the 1970s from the General Social Survey. The pattern is clear: ordinary citizens are skeptical and wary. They want less regulation and do not trust regulators to do what is right. The mistrust has become stronger over time. However, the public supports environmental and electricity rate regulation. These sentiments are shared across age, sex, race, education, and income groups and the left/right ideological spectrum. The public tends to oppose less traditional regulation, such as wage and price controls, government ownership of some industries, and regulation of steel prices. But there is less consensus across demographic groups: blacks, the less educated, and low-income groups are less hostile, or marginally friendly, to less conventional modes of regulation. The paper concludes by contrasting public opinion with the path of regulation since the 1970s.
{"title":"Public Opinion about Regulation","authors":"S. Peltzman","doi":"10.1086/723572","DOIUrl":"https://doi.org/10.1086/723572","url":null,"abstract":"The paper describes how ordinary citizens view economic regulation and summarizes answers to questions about regulation and regulators since the 1970s from the General Social Survey. The pattern is clear: ordinary citizens are skeptical and wary. They want less regulation and do not trust regulators to do what is right. The mistrust has become stronger over time. However, the public supports environmental and electricity rate regulation. These sentiments are shared across age, sex, race, education, and income groups and the left/right ideological spectrum. The public tends to oppose less traditional regulation, such as wage and price controls, government ownership of some industries, and regulation of steel prices. But there is less consensus across demographic groups: blacks, the less educated, and low-income groups are less hostile, or marginally friendly, to less conventional modes of regulation. The paper concludes by contrasting public opinion with the path of regulation since the 1970s.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"65 1","pages":"S327 - S353"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86954327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peltzman’s work is revisited in light of two recent opportunities to quantitatively assess trade-offs in drug regulation. First, reduced regulatory barriers to drug manufacturing associated with the 2017 reauthorization of generic-drug user fee amendments were followed by more entry and lower prices for prescription drugs. A simple, versatile industry model and historical data on entry indicate that easing restrictions on generics discourages innovation, but this cost is more than offset by benefits from enhanced competition, especially after 2016. Second, accelerated vaccine approval in 2020 had unprecedented net benefits as it improved health and changed the trajectory of the wider economy. Evidence suggests that cost-benefit analysis of Food and Drug Administration (FDA) regulation is incomplete without accounting for substitution toward potentially unsafe and ineffective treatments that are outside FDA jurisdiction and heavily utilized before FDA approval. Moreover, the policy processes initiating the regulatory changes show an influence of Peltzman’s findings. Consumer losses from purchases of ineffective drugs or hastily marketed unsafe drugs appear to have been trivial compared to gains from innovation. (Peltzman 1974, p. 82) Consumer losses from purchases of ineffective drugs or hastily marketed unsafe drugs appear to have been trivial compared to gains from innovation. (Peltzman 1974, p. 82)
佩尔兹曼的工作在最近的两次定量评估药物监管权衡的机会中被重新审视。首先，与2017年仿制药用户费用修订再授权相关的药品生产监管壁垒降低，随后处方药进入更多，价格更低。一个简单、通用的行业模型和进入市场的历史数据表明，放宽对仿制药的限制会阻碍创新，但这种成本被竞争加剧带来的好处所抵消，尤其是在2016年之后。其次，2020年加快疫苗审批带来了前所未有的净效益，因为它改善了健康状况，改变了更广泛的经济轨迹。有证据表明，如果不考虑在FDA管辖范围之外、在FDA批准之前大量使用的潜在不安全和无效治疗的替代，食品和药物管理局(FDA)法规的成本效益分析是不完整的。此外，启动监管变化的政策过程显示出Peltzman研究结果的影响。与创新带来的收益相比，消费者因购买无效药物或匆忙销售不安全药物而遭受的损失似乎微不足道。(Peltzman 1974, p. 82)消费者因购买无效药品或匆忙销售不安全药品而遭受的损失，与创新带来的收益相比似乎微不足道。(佩尔兹曼1974，第82页)
{"title":"Peltzman Revisited: Quantifying 21st-Century Opportunity Costs of Food and Drug Administration Regulation","authors":"C. Mulligan","doi":"10.1086/721270","DOIUrl":"https://doi.org/10.1086/721270","url":null,"abstract":"Peltzman’s work is revisited in light of two recent opportunities to quantitatively assess trade-offs in drug regulation. First, reduced regulatory barriers to drug manufacturing associated with the 2017 reauthorization of generic-drug user fee amendments were followed by more entry and lower prices for prescription drugs. A simple, versatile industry model and historical data on entry indicate that easing restrictions on generics discourages innovation, but this cost is more than offset by benefits from enhanced competition, especially after 2016. Second, accelerated vaccine approval in 2020 had unprecedented net benefits as it improved health and changed the trajectory of the wider economy. Evidence suggests that cost-benefit analysis of Food and Drug Administration (FDA) regulation is incomplete without accounting for substitution toward potentially unsafe and ineffective treatments that are outside FDA jurisdiction and heavily utilized before FDA approval. Moreover, the policy processes initiating the regulatory changes show an influence of Peltzman’s findings. Consumer losses from purchases of ineffective drugs or hastily marketed unsafe drugs appear to have been trivial compared to gains from innovation. (Peltzman 1974, p. 82) Consumer losses from purchases of ineffective drugs or hastily marketed unsafe drugs appear to have been trivial compared to gains from innovation. (Peltzman 1974, p. 82)","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"125 1","pages":"S355 - S387"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74809152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Racial segregation by businesses during Jim Crow was often voluntary and practiced without a legal mandate. Voluntary segregation can be driven by profit-motivated business owners catering to racist white customers or discrimination by business owners. We assess the relative importance of customers’ and firms’ discrimination by examining the 1953 desegregation of Washington, DC, movie theaters, which occurred rapidly because of a Supreme Court ruling affecting only businesses in Washington. Using weekly data for a nationwide sample of theaters, we find that revenues of Washington theaters fell relative to other theaters, consistent with reduced demand from biased white customers. We use a test for firms’ discrimination based on a model of the screening decision for films with black actors cast in prominent roles. We cannot reject that the run length of these films was profit motivated. Together, our results point toward customer discrimination as a primary cause of public accommodation segregation.
{"title":"Why Did Firms Practice Segregation? Evidence from Movie Theaters during Jim Crow","authors":"Ricard Gil, J. Marion","doi":"10.1086/720904","DOIUrl":"https://doi.org/10.1086/720904","url":null,"abstract":"Racial segregation by businesses during Jim Crow was often voluntary and practiced without a legal mandate. Voluntary segregation can be driven by profit-motivated business owners catering to racist white customers or discrimination by business owners. We assess the relative importance of customers’ and firms’ discrimination by examining the 1953 desegregation of Washington, DC, movie theaters, which occurred rapidly because of a Supreme Court ruling affecting only businesses in Washington. Using weekly data for a nationwide sample of theaters, we find that revenues of Washington theaters fell relative to other theaters, consistent with reduced demand from biased white customers. We use a test for firms’ discrimination based on a model of the screening decision for films with black actors cast in prominent roles. We cannot reject that the run length of these films was profit motivated. Together, our results point toward customer discrimination as a primary cause of public accommodation segregation.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"16 1","pages":"635 - 663"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81274452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In 2002, India introduced a legal reform that allowed secured creditors to seize and liquidate a defaulter’s assets, thereby strengthening creditors’ rights. We study the impact of the legal change on firms’ real decisions regarding their capital and labor, exploiting variation in their prepolicy proportion of collateralizable assets. We find that firms increased employment and reduced their capital investments. These effects are especially strong for firms in regions with less-efficient courts. Our results are consistent with an increased threat of liquidation for firms following the passage of the law.
{"title":"Creditors’ Rights, Threat of Liquidation, and the Labor and Capital Choices of Firms","authors":"Shashwat Alok, Ritam Chaurey, Vasudha Nukala","doi":"10.1086/720962","DOIUrl":"https://doi.org/10.1086/720962","url":null,"abstract":"In 2002, India introduced a legal reform that allowed secured creditors to seize and liquidate a defaulter’s assets, thereby strengthening creditors’ rights. We study the impact of the legal change on firms’ real decisions regarding their capital and labor, exploiting variation in their prepolicy proportion of collateralizable assets. We find that firms increased employment and reduced their capital investments. These effects are especially strong for firms in regions with less-efficient courts. Our results are consistent with an increased threat of liquidation for firms following the passage of the law.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"105 1","pages":"687 - 714"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85889717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Medical innovation is perhaps the most important driver of health care spending and quality. Economists have studied pharmaceutical innovation for decades, and their findings have contributed to the debate about optimal Food and Drug Administration policy. Despite their importance to health care spending and value, there is no similar literature to inform an optimal regulation system for novel and valuable medical procedures. In this paper, we begin to fill this gap by documenting the incentives for developing medical procedures and the process through which they are approved for use. Drawing on the work of Sam Peltzman and George Stigler, we argue that the largely ad hoc system of rewards and review for medical procedures may explain the slow pace of innovation, particularly when compared with drug innovation.
医疗创新可能是医疗保健支出和质量的最重要驱动因素。经济学家研究制药创新已有数十年，他们的研究结果为有关食品和药物管理局(Food and Drug Administration)最佳政策的辩论做出了贡献。尽管它们对医疗保健支出和价值很重要，但没有类似的文献来为新颖和有价值的医疗程序提供最佳的监管系统。在这篇论文中，我们开始通过记录发展医疗程序的动机和它们被批准使用的过程来填补这一空白。根据萨姆·佩尔兹曼和乔治·斯蒂格勒的研究，我们认为，医疗程序的奖励和审查制度在很大程度上是临时的，这可能解释了创新步伐缓慢的原因，尤其是与药物创新相比。
{"title":"The Returns to Medical Inventions","authors":"David Dranove, Craig L. Garthwaite, Bingxiao Wu","doi":"10.1086/723416","DOIUrl":"https://doi.org/10.1086/723416","url":null,"abstract":"Medical innovation is perhaps the most important driver of health care spending and quality. Economists have studied pharmaceutical innovation for decades, and their findings have contributed to the debate about optimal Food and Drug Administration policy. Despite their importance to health care spending and value, there is no similar literature to inform an optimal regulation system for novel and valuable medical procedures. In this paper, we begin to fill this gap by documenting the incentives for developing medical procedures and the process through which they are approved for use. Drawing on the work of Sam Peltzman and George Stigler, we argue that the largely ad hoc system of rewards and review for medical procedures may explain the slow pace of innovation, particularly when compared with drug innovation.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"111 1","pages":"S389 - S417"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88979902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we examine whether same-sex marriage legalization announcements impact the occurrence of hate crimes against lesbian, gay, bisexual, and transgender (LGBT) people. Using a difference-in-differences design, we exploit the variation in the timing of same-sex marriage legalization announcements across states. On average, a same-sex marriage legalization announcement reduces the anti-LGBT hate crime rate by .112 per 100,000 people, although some additional analyses have weaker results. Decreases are mostly driven by reductions in violent crimes. Event-study estimates show that results fade after 1 year and provide evidence that reductions are not due to changes in social trends before an announcement. Our results demonstrate that salient, progressive LGBT policy announcements may, by themselves, effectively reduce anti-LGBT hate crimes.
{"title":"Pride and Prejudice: Same-Sex Marriage Legalization Announcements and Hate Crimes","authors":"R. Pettis, Zehra Valencia, B. Williams","doi":"10.1086/721700","DOIUrl":"https://doi.org/10.1086/721700","url":null,"abstract":"In this paper, we examine whether same-sex marriage legalization announcements impact the occurrence of hate crimes against lesbian, gay, bisexual, and transgender (LGBT) people. Using a difference-in-differences design, we exploit the variation in the timing of same-sex marriage legalization announcements across states. On average, a same-sex marriage legalization announcement reduces the anti-LGBT hate crime rate by .112 per 100,000 people, although some additional analyses have weaker results. Decreases are mostly driven by reductions in violent crimes. Event-study estimates show that results fade after 1 year and provide evidence that reductions are not due to changes in social trends before an announcement. Our results demonstrate that salient, progressive LGBT policy announcements may, by themselves, effectively reduce anti-LGBT hate crimes.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"34 1","pages":"811 - 835"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82974012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
How does a change in the cost of advertising affect product prices? On the one hand, advertising increases costs, but on the other hand, advertising is expected to generate more sales, so the impact on product prices and profits depends on the magnitude of these two effects. In this article I describe some recent trends in online and offline advertising and build a simple model of an online merchant. In this model when advertising becomes more costly, the merchant cuts back on ad spending, but it does not necessarily change product prices.
{"title":"Advertising Costs and Product Prices","authors":"H. Varian","doi":"10.1086/721269","DOIUrl":"https://doi.org/10.1086/721269","url":null,"abstract":"How does a change in the cost of advertising affect product prices? On the one hand, advertising increases costs, but on the other hand, advertising is expected to generate more sales, so the impact on product prices and profits depends on the magnitude of these two effects. In this article I describe some recent trends in online and offline advertising and build a simple model of an online merchant. In this model when advertising becomes more costly, the merchant cuts back on ad spending, but it does not necessarily change product prices.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"55 1","pages":"S419 - S431"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76209964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Today one cannot imagine antitrust litigation without the use of economic experts. Defendants and plaintiffs alike pay handsomely for their reports and testimony. However, the use of economists as expert witnesses did not begin until the iconic case of United States v. United States Steel, when two prominent economists, Francis Walker and Jeremiah Jenks, testified on behalf of the Department of Justice and United States Steel. Drawing on the original trial transcript, this paper assesses their role in the litigation. While their level of theoretical sophistication and empirical analysis falls short of today’s standards, the testimony of Walker and Jenks featured some of the same elements of expert testimony that continue today and analysis that was a precursor to the Chicago School’s perspective on competition.
今天，人们无法想象在没有经济学专家的情况下进行反垄断诉讼。被告和原告都为他们的报告和证词支付了可观的报酬。然而，直到标志性的美国诉美国钢铁公司案(United States v. United States Steel)才开始使用经济学家作为专家证人，当时两位著名经济学家弗朗西斯·沃克(Francis Walker)和耶利米·詹克斯(Jeremiah Jenks)代表司法部和美国钢铁公司作证。根据原始审判记录，本文评估了他们在诉讼中的作用。虽然他们的理论复杂性和实证分析水平低于今天的标准，但沃克和詹克斯的证词中有一些专家证词的相同元素，这些元素今天仍在继续，并且分析是芝加哥学派竞争观点的先驱。
{"title":"In the Beginning: The Creation of the Economic Expert in Antitrust","authors":"K. Elzinga","doi":"10.1086/721265","DOIUrl":"https://doi.org/10.1086/721265","url":null,"abstract":"Today one cannot imagine antitrust litigation without the use of economic experts. Defendants and plaintiffs alike pay handsomely for their reports and testimony. However, the use of economists as expert witnesses did not begin until the iconic case of United States v. United States Steel, when two prominent economists, Francis Walker and Jeremiah Jenks, testified on behalf of the Department of Justice and United States Steel. Drawing on the original trial transcript, this paper assesses their role in the litigation. While their level of theoretical sophistication and empirical analysis falls short of today’s standards, the testimony of Walker and Jenks featured some of the same elements of expert testimony that continue today and analysis that was a precursor to the Chicago School’s perspective on competition.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"1 1","pages":"S519 - S542"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79916894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The net effect of vertical integration on consumer welfare depends on the magnitude of the price reductions resulting from the elimination of double marginalization at the integrated firm and the price increases resulting from higher input prices charged to unintegrated competitors. In this paper, we estimate both of these effects in the US gasoline industry by examining the change in relative retail gasoline prices following the vertical separation caused by refiners’ decision to exit gasoline retailing beginning in the mid-2000s. Using station-level price data from Florida and New Jersey, we find that double marginalization caused retail prices to increase by about 1.2 cents per gallon. Estimates of the effect of raising rivals’ costs, while sensitive to the choice of control group, are of a similar magnitude. On net, we find that the average retail price of gasoline was effectively unchanged as the result of vertical separation.
{"title":"Vertical Disintegration: The Effect of Refiners’ Exit from Gasoline Retailing on Retail Gasoline Pricing","authors":"Daniel Hosken, Christopher T. Taylor","doi":"10.1086/718427","DOIUrl":"https://doi.org/10.1086/718427","url":null,"abstract":"The net effect of vertical integration on consumer welfare depends on the magnitude of the price reductions resulting from the elimination of double marginalization at the integrated firm and the price increases resulting from higher input prices charged to unintegrated competitors. In this paper, we estimate both of these effects in the US gasoline industry by examining the change in relative retail gasoline prices following the vertical separation caused by refiners’ decision to exit gasoline retailing beginning in the mid-2000s. Using station-level price data from Florida and New Jersey, we find that double marginalization caused retail prices to increase by about 1.2 cents per gallon. Estimates of the effect of raising rivals’ costs, while sensitive to the choice of control group, are of a similar magnitude. On net, we find that the average retail price of gasoline was effectively unchanged as the result of vertical separation.","PeriodicalId":22657,"journal":{"name":"The Journal of Law and Economics","volume":"37 4 1","pages":"423 - 464"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89389513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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