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41.
This paper applies an intuitive approach based on stock market data to a unique dataset of large concentrations during the period 1990–2002 to assess the effectiveness of European merger control. The basic idea is to relate announcement and decision abnormal returns. Under a set of four maintained assumptions, merger control might be interpreted to be effective if rents accruing due to the increased market power observed around the merger announcement are reversed by the antitrust decision, i.e. if there is a negative relation between announcement and decision abnormal returns. To clearly identify the events' competitive effects, we explicitly control for the market expectation about the outcome of the merger control procedure and run several robustness checks to assess the role of our maintained assumptions. We find that only outright prohibitions completely reverse the rents measured around a merger's announcement. On average, remedies seem to be only partially capable of reverting announcement abnormal returns. Yet they seem to be more effective when applied during the first rather than the second investigation phase and in subsamples where our assumptions are more likely to hold. Moreover, the European Commission appears to learn over time.  相似文献   
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We show that attractiveness, as measured by facial symmetry, leads to greater rewards in professional sports. National Football League quarterbacks who are more attractive are paid greater salaries and this premium persists after controlling for player performance.  相似文献   
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Abstract Under congestion pricing, Canadian airports would annually save between $72 and $105 million. Social costs per landing and takeoff decrease about $300 at Toronto and Vancouver and $50 at Calgary and Montreal. Slot constraints fail to eliminate this airport congestion. Congestion prices are lower on average than existing weight‐based prices. Current airport capacity accommodates at least five more years of traffic growth before congestion reaches current levels. Substantial welfare gains occur even if dominant airlines already internalize their self‐imposed delays. This article calculates equilibrium congestion pricing schedules, traffic rates, queuing delays, layover times, and connection times by time of day.  相似文献   
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学生写作中经常出现词汇、语法、措辞等方面的错误,教师在教学中应分析其错误形成的原因,正确对待其错误,努力改进教学方法和评价手段,鼓励学生自主学习,以提高学生文化修养和作文质量。  相似文献   
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从测试理论,测试实践和改进措施三方面评析了CET-4测试目标,认为其信度和效度各有高低的一面,提高CET-4通过率的根本出路在于英语水平的提高。  相似文献   
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While the tourism sector shifts towards digital transformation, Destination Management Organisations (DMOs) often struggle to adapt to their changing technological environment. This study explores the antecedents of digital collaboration and develops a framework for micro-DMOs to enhance effective destination management through digital technologies. An integrated sequential qualitative approach was adopted by conducting multi-phase interviews, in addition to designing and trialling a real-world trial digital platform. The research provides empirical evidence that digital collaboration is essential for micro-DMOs, necessitating them to transform their current “websites” into digital platforms which act as a hub for business stakeholders to actively be involved in. Antecedents of successful digital collaboration include mutuality, trust, control, and leadership which may be manifested differently from non-digital collaboration. Additionally, the study identifies three aspects for digital collaboration; marketing, networking and knowledge sharing that demands specific attention. Our results have theoretical, methodological, and practical implications for academia, industry and policymakers.  相似文献   
48.
Validating the international tourist role scale   总被引:1,自引:0,他引:1  
This study was designed to validate the international tourist role scale and the three dimensions it revealed. The purpose of this attitudinal scale was to measure the tourist role typology. United States adult outbound tourists flying with 11 major airlines returned useful questionnaires. This study validated the role scale as a reliable one that properly identified three conceptual dimensions of international tourist typology and successfully provided measures of tourists’ novelty-seeking preferences on the three dimensions. The study demonstrated, however, that the scale would measure the novelty-seeking preferences of international tourists more effectively if it were supplemented by other measures.  相似文献   
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文章通过选取几种不同的絮凝剂进行研究,来选出对木糖废水处理效果最佳的絮凝剂及其最佳絮凝条件、最佳去除率。从硫酸铝、三氯化铝、PAC、硫酸铁、硫酸亚铁、三氯化铁中选出PAC和Al2(SO4)3,然后针对这两种絮凝剂,研究确定其最佳絮凝条件及最大去除率。PAC的最佳实验条件为:投加量为1.6 g/L,pH=6,快速搅拌时间为30 s,沉降时间为30 min;Al2(SO4)3的最佳实验条件为:投加量为1 g/L,原水pH=6,快速搅拌时间为90 s,沉降时间为30 min。絮凝效果为:COD去除率分别为82.3%和75.38%,色度去除率都达到了90%以上。  相似文献   
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