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51.
The general consensus in the volatility forecasting literature is that high-frequency volatility models outperform low-frequency volatility models. However, such a conclusion is reached when low-frequency volatility models are estimated from daily returns. Instead, we study this question considering daily, low-frequency volatility estimators based on open, high, low, and close daily prices. Our data sample consists of 18 stock market indices. We find that high-frequency volatility models tend to outperform low-frequency volatility models only for short-term forecasts. As the forecast horizon increases (up to one month), the difference in forecast accuracy becomes statistically indistinguishable for most market indices. To evaluate the practical implications of our results, we study a simple asset allocation problem. The results reveal that asset allocation based on high-frequency volatility model forecasts does not outperform asset allocation based on low-frequency volatility model forecasts.  相似文献   
52.
Our purpose is to explore the concept of “sustainability” when understood from a performative perspective, i.e. as a concept that is filled with meaning across time. Drawing on a 10 year-long study of the digital footprint of Stockholm Royal Seaport, claimed to be northern Europe's largest sustainable urban development district, we show that “sustainability” emerged as the project became associated with particular places, projects, histories, and technologies. This means that “sustainability” was local in that it was situated in the particular spatial context of the project; temporal in that it was situated in a particular time; and political in that it expressed particular values and perspectives. The study contributes to explaining why “sustainability” remains—and always will remain—a contested concept, which is why sustainability transitions are complex. Consequently, we suggest that the transition towards sustainability always involves the transition of sustainability, something that needs to be acknowledged in order for a transition to actually become sustainable.  相似文献   
53.
Both soft, noncontractible, and hard, contractible, information are informative about managerial ability and future firm performance. If a manager's future compensation depends on expectations of ability or future performance, then the manager has implicit incentives to affect the information. We examine the real incentive effects of soft information in a dynamic agency with limited commitment. When long-term contracts are renegotiated, the rewards for future performance inherent in long-term contracts allow the principal partial control over the implicit incentives. This is because the soft information affects the basis for contract renegotiation. With short-term contracts, the principal has no control over the basis for contract negotiation, and thus long-term contracts generally dominate short-term contracts. With long-term contracts, the principal's control over implicit incentives is characterized in terms of effective contracting on an implicit aggregation of the soft information that arises from predicting (forming expectations of) future performance. We provide sufficient conditions for soft information to have no real incentive effects. In general, implicit incentives not controllable by the principal include fixed effects, such as career concerns driven by labor markets external to the agency. When controllable incentives span the fixed effects of career concerns, the latter have no real effects with regard to total managerial incentives—they would optimally be the same with or without career concerns. Our analysis suggests empirical tests for estimating career concerns that should explicitly incorporate noncontractible information.  相似文献   
54.
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   
55.
吕波  王辉  何悦  周仲鸿 《科技和产业》2021,21(10):252-259
探究黑龙江旅游网络关注度时空演变特征对黑龙江旅游业良性发展具有重要意义.利用百度指数获取2011—2018年全国和分地区黑龙江旅游网络关注度逐日搜索指数数据.从时间分布、空间分布、时空集聚3个方面研究其演变特征.研究表明:2011—2018年全国黑龙江旅游网络关注度年际变化总体呈现上升趋势,月际变化呈"W"形;2011—2018年31个省区市黑龙江旅游网络关注度空间差异较大、季节性影响显著;东部地区黑龙江旅游网络关注度偏高,西部地区黑龙江旅游网络关注度的季节差异最明显;东部地区内的黑龙江旅游网络关注度差异性最小,西部地区内差异性最大;黑龙江旅游网络关注度具有正空间自相关,部分东部、中部地区表现为高高集聚,多数西部地区表现为低低集聚.  相似文献   
56.
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   
57.
The study reported in this paper investigated the determinants of fair trade (FT) product purchase intention among Dutch consumers according to the extended Theory of Planned Behaviour and determined whether the effects of those determinants differ between male and female consumers. To test the various research hypotheses, an online survey with 499 respondents from a Dutch research panel was employed. Results of the multi-group analysis using a structural equation modelling approach reveal that FT product purchase intention of both male and female consumers are predicated on moral obligation and self-identity. The impact of subjective norm on purchase intention is statistically significant for male consumers only. Analyses reveal that, indeed, the impact of subjective norm on FT product purchase intention is moderated by consumers’ gender.  相似文献   
58.
59.
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   
60.
Motor carrier safety is an important concern of shippers, carriers, policy makers, consignees, insurance providers, and the motoring public. One aspect of carrier safety that has garnered substantial attention is whether carriers making greater use of owner–operators are more or less safe vis‐à‐vis carriers making greater use of employee drivers. Currently, conflicting theoretical predictions exist regarding the direction of this relationship. In this article, we offer a reconciliation of the alternative theoretical predictions by developing a coherent theory that merges sociological rational choice theory and theory regarding motor carrier safety. We subject our theory to empirical testing by fitting a series of seemingly unrelated regression models to a vector of safety measures tracked as part of the Federal Motor Carrier Safety Administration's Compliance, Safety, and Accountability program. Our results are consistent with our proposed theory of owner—operator safety and provide meaningful theoretical and managerial implications and directions for future research.  相似文献   
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