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41.
The new regulatory framework in the digital sector in Europe is likely to fall short of expectations. A fragmented digital market with insuffi cient incentives for investment is the probable outcome. European regulators should abandon their approach in favour of a new and more flexible set of ideas discussed in this paper.  相似文献   
42.
Bio-economic modelling has become a useful tool for anticipating the outcomes of policies and technologies before their implementation. Advances in mathematical programming have made it possible to build more comprehensive models. In an overview of recent studies about bio-economic models applied to land-use problems in agriculture and forestry, we evaluated how aspects such as uncertainty, multiple objective functions, system dynamics and time have been incorporated into models. We found that single objective models were more frequently applied at the farm level, while multiple objective modelling has been applied to meet concerns at the landscape level. Among the objectives, social aspects are seldom represented in all models, when being compared to economic and environmental aspects. The integration of uncertainty is occasionally a topic, while stochastic approaches are more frequently applied than non-stochastic robust methods. Most multiple-objective models do not integrate uncertainty or sequential decision making. Static approaches continue to be more recurrent than truly dynamic models. Even though integrating multiple aspects may enhance our understanding of a system; it involves a tradeoff between complexity and robustness of the results obtained. Land-use models have to address this balance between complexity and robustness in order to evolve towards robust multiple-objective spatial optimization as a prerequisite to achieve sustainability goals.  相似文献   
43.
In this article, we account for the first time for long memory, regime switching and the conditional time-varying volatility of volatility (heteroscedasticity) to model and forecast market volatility using the heterogeneous autoregressive model of realized volatility (HAR-RV) and its extensions. We present several interesting and notable findings. First, existing models exhibit significant nonlinearity and clustering, which provide empirical evidence on the benefit of introducing regime switching and heteroscedasticity. Second, out-of-sample results indicate that combining regime switching and heteroscedasticity can substantially improve predictive power from a statistical viewpoint. More specifically, our proposed models generally exhibit higher forecasting accuracy. Third, these results are widely consistent across a variety of robustness tests such as different forecasting windows, forecasting models, realized measures, and stock markets. Consequently, this study sheds new light on forecasting future volatility.  相似文献   
44.
知识互动程度评价对改善高校跨学科创新团队知识互动具有重要意义。在界定高校跨学科创新团队知识互动及知识互动程度内涵的基础上,创新性地从知识互动深度、互动广度、互动时间3个维度建立知识互动程度评价指标体系。进一步地,采用三角模糊权重、熵权和模糊积分相结合的方法,构建知识互动程度评价模型。最后,选取一所高校跨学科创新团队进行实例分析,验证评价模型的可操作性,可为高校跨学科创新团队知识互动程度评价提供一个新视角。  相似文献   
45.
目的探讨纤维蛋白胶(FG)粘合法联合神经生长因子(NGF)治疗周围神经损伤的临床疗效。方法选取我院2006年8月至2013年10月就诊的124例腓总神经损伤患者,随机均分为两组,对照组患者单纯使用缝合法,试验组患者在缝合法的基础上配合使用FG粘合法联合NGF治疗,随访6个月以上,分析两组患者的运动功能和患肢感觉疗效。结果试验组患者总有效率明显优于对照组,差异有统计学异议(P<0.05)。结论周围神经损伤的修复与再生过程中使用FG粘合法联合NGF治疗,可有效改善患者症状,安全性高,不良反应较少。  相似文献   
46.
Amid increasing interest in firm age and its effects on firm performance, this special issue offers an exhaustive review of the literature and a novel collection of evidence on the effects of firm age on performance, including a special focus of interest on innovation performance, financial performance, exports, survival and growth. This editorial positions the theme in the extant literature, and provides key definitions and challenges ahead in the field of evolutionary economics. It introduces the collection of articles composing the special issue. The papers offer a diversity of country contexts, as well as analytical approaches and methods. They include an exhaustive review of the literature on age and firms’ performance, and present original empirical studies focusing on the effects of age on firms’ economic outcomes on the one hand, and on innovation outcomes on the other hand. While most of the papers use econometric analysis, the level of analysis ranges from firm to individual.  相似文献   
47.
Disclosure standards mandate the quantitative disclosure of hedging‐instrument‐related risks but not the disclosure of hedged‐item‐related risks. We examine how a match (mismatch) in formats, caused by making quantitative (qualitative) hedged item disclosures alongside quantitative hedging instrument disclosures, affects investors' integration of information from these two related disclosures. Our first experiment varies the hedged item disclosure format (quantitative or qualitative) and the portion of risk hedged (small or large). We find that when disclosure formats are mismatched, the less comparable nature of the two disclosures caused investors to neglect the offsetting relationship when assessing net risks. As a result, risk and investment judgments were influenced by the more prominent quantitative hedging instrument disclosures. Our second experiment finds that the use of a qualitative debiaser that clarifies the relationship between the two disclosures led to the integration of information and mitigated this effect.  相似文献   
48.
The choice argument against sweatshop regulations states that public officials should not prohibit workers from accepting jobs that require long hours, low pay, and poor working conditions, because enforcing such regulations would be disrespectful to the workers who choose to work in sweatshops. Critics of the choice argument reply that these regulations can be justified when workers only choose to work in sweatshops because they lack acceptable alternatives and are unable to coordinate to achieve better conditions for all workers. My thesis is that the presence of unacceptable alternatives to sweatshop labor or barriers to coordination cannot justify sweatshop regulations such as minimum wage and maximum hour laws. Although officials should promote alternatives to difficult and dangerous sweatshop labor, they should not do so by limiting workers’ and employers’ options through coercive regulation. And the fact that sweatshop workers may face coordination problems does not undermine the claim that sweatshop workers choose to work in sweatshops, just as other workers face coordination problems but nevertheless make occupational choices. Furthermore, efforts to restrict sweatshop workers’ choices are morally risky and may not promote workers’ wellbeing or wellbeing in general.  相似文献   
49.
50.
The aim of this research is to investigate the web of business-stakeholder relationships emerging from first integrated reports. Drawn from the stakeholder salience theory, the analysis focuses on some factors that may cause specific stakeholders to be crucial for some organizations and their ability to create value over time. More precisely, findings highlight the importance of industry membership, while entities’ nationality seems not to be a differentiating element. This study contributes to the corporate disclosure literature by analyzing an emerging reporting tool, the integrated report, and demonstrating that the link between some business characteristics and stakeholder salience seems fundamental for the representation of the impact of corporate social and environmental responsibilities on the economic performance. From a practical point of view, the impact of industry membership on corporate disclosures encourages the drafting of differentiated reporting standards across sectors, in order to improve comparability, materiality, and reliability of information.  相似文献   
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