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951.
The growing internet concern (IC) over the crude oil market and related events influences market trading, thus creating further instability within the oil market itself. We propose a modeling framework for analyzing the effects of IC on the oil market and for predicting the price volatility of crude oil’s futures market. This novel approach decomposes the original time series into intrinsic modes at different time scales using bivariate empirical mode decomposition (BEMD). The relationship between the oil price volatility and IC at an individual frequency is investigated. By utilizing decomposed intrinsic modes as specified characteristics, we also construct extreme learning machine (ELM) models with variant forecasting schemes. The experimental results illustrate that ELM models that incorporate intrinsic modes and IC outperform the baseline ELM and other benchmarks at distinct horizons. Having the power to improve the accuracy of baseline models, internet searching is a practical way of quantifying investor attention, which can help to predict short-run price fluctuations in the oil market.  相似文献   
952.
Recent decades have seen a fundamental shift in the nature of economic regulation in the United States. Unauthorized by congress, and largely unnoted in legal and academic circles, regulatory agencies such as the Federal Communications Commission have changed the regulatory process by linking otherwise unrelated regulatory issues. Examples include tying merger approval to firm commitments to engage in conceptually unrelated build‐outs and other projects of political importance. This linking of issues has several effects, the most prominent being (a) tying regulatory issues changes the outcomes obtained, plausibly in predictable ways; (b) tying in some circumstances allows regulators to extend their authority to issues for which they have little or no legal authority; and (c) tied regulatory bargaining fails to produce valid legal precedent for firm decision making. We provide an analysis of these conclusions by examining the increasing use of consent decrees, voluntary merger commitments, and merger conditions by the Federal Communications Commission, referencing our discussion with a simple model of joint bargaining applicable to regulatory practice.  相似文献   
953.
A problem with index number methods for computing TFP growth is that during recessions these methods show declines in TFP. This is rather implausible since it implies technological regress. We develop a new method to decompose TFP growth into technical progress and inefficiency arising from the short run fixity of capital and labour, and apply this to new data on the US corporate nonfinancial sector and the noncorporate nonfinancial sector. The analysis sheds light on sources of the productivity growth slowdowns over the period 1960–2014.  相似文献   
954.
We examined how factors from Indigenous entrepreneurship research (social capital, cultural capital, self-efficacy) help explain the high level of Māori entrepreneurial performance in the mainstream screen industry. Results, based on ten case studies and a one-year series of structured interviews, extend prior research by showing that these Indigenous entrepreneurs benefit jointly from two forms of capital: cultural and social. We found high levels of both forms to increase the desire for emancipation of cultural and community identity – not just individual identity – through entrepreneurship. Self-efficacy and storytelling helped ameliorate discontinuities across Indigenous and mainstream contexts. Our research sheds new light on how Indigenous ventures can pursue mainstream entrepreneurship while maintaining cultural identity. It also makes several distinct contributions to the Indigenous entrepreneurship literature. First, it provides an integrative theoretic review. Second, it illustrates a culturally appropriate methodology for researching Māori entrepreneurs with implications for other Indigenous communities. Third, it proposes cultural capital and social capital as a two-part framework for explaining Indigenous entrepreneurial action. Fourth, it shows how entrepreneurship can be empowering for Indigenous communities. Finally, our paper demonstrates that entrepreneurship is a promising mechanism for preserving and promoting the cultures of Māori and other Indigenous peoples.  相似文献   
955.
We propose a new framework exploiting realized measures of volatility to estimate and forecast extreme quantiles. Our realized extreme quantile (REQ) combines quantile regression with extreme value theory and uses a measurement equation that relates the realized measure to the latent conditional quantile. Model estimation is performed by quasi maximum likelihood, and a simulation experiment validates this estimator in finite samples. An extensive empirical analysis shows that high‐frequency measures are particularly informative of the dynamic quantiles. Finally, an out‐of‐sample forecast analysis of quantile‐based risk measures confirms the merit of the REQ.  相似文献   
956.
There is no single ‘great’ commodity frontier whose exploitation under current socio‐technical conditions could fuel capital accumulation at the global scale. According to Jason Moore, this represents the ‘end of Cheap Nature’ and signals a terminal crisis for capitalism as we know it. In this article we complicate this assertion by showing how, in the context of global environmental governance frameworks of carbon control, a diverse range of actors situated at multiple scales are intensifying the use of cities and their hinterlands for the production/transgression of localized commodity frontiers. We draw on scholarship on uneven geographical development, state‐led restructuring and eco‐scalar fixes to present two case studies from different segments of the carbon cycle in the global South. The first case demonstrates how the introduction of waste‐to‐energy technology in Delhi facilitated the generation of ‘carbon credits’ while waste matter itself became a commodity. The second discusses attempts by the Brazilian state of Amazonas (Amazônia) aspiring to shift from rainforest exploitation to financialized conservation supported by the ‘green global city’ functions of metropolitan Manaus. These cases demonstrate that although the global carbon‐control regime may enable accumulation, implementation remains speculative, and localized commodity frontiers provoke social resistances that jeopardize their durability.  相似文献   
957.
958.
Theories of aspiration level effects predict that decisions under uncertainty will depend on whether performance is above or below some target level of performance. A sample of 5000 quarterly earnings announcements by publicity held companies listed on the COMPUSTAT and CRSP data bases is examined to test this hypothesis. Four models from the current accounting literature are used as alternative estimates of the target level of earnings for these firms. When earnings are announced the difference between actual and forecast earnings, here called a forecast error, can be computed. The data indicate that the relationship between valuation and forecast error differs conditional on the sign of the forecast error.  相似文献   
959.
ABSTRACT

Based on the theoretical foundation of emotion regulation, this exploratory study aimed to examine changes in tourists’ perceived well-being and to determine whether these changes were due to use of emotion regulation strategies (ERSs) during their vacation. This study used travel diaries to record tourists’ use of ERSs on a daily basis, and also measured tourists’ perceived well-being one day before and after their vacation. Results indicated that tourists had significantly higher perceptions of well-being after vacation, and those who used ERSs were more likely to indicate a higher sense of well-being after vacation. The results provide new insight into which aspects of tourists’ subjective and psychological well-being can be boosted by taking vacations and how these aspects may be enhanced by using different ERSs.  相似文献   
960.
Replanning is often used to optimize results of an activity in an ever changing world. To address the challenge of preparing future engineers for success, a special course was created for all engineering freshmen of the Faculty of Engineering of the University of Porto, in Portugal. Presented as a case study, this special course underwent a careful replanning as a result of several years of experience in teaching practice alongside with a theoretical deepening in pedagogical and technological issues, under the aegis of the action-research methodology. Within the context of the case study course, the mentioned replanning was also based on a theoretical approach that clearly identifies teaching–learning-assessment methodologies that promote regulation from those that foster emancipation, using a specific instrument: a taxonomy of educational processes. The replanning was designed to globally boost results regarding the educational aims of the course such as furthering freshmen’s integration into work environment and preparing them for success by fostering transversal skills (needed for study and work). Technology is seen as a mean of education enrichment as well as a productivity tool. The introduced innovations include fun-but-educational activities, several types of assessment over time and specific technological tools which were critical for the educational impact/achievement of this course. Success is demonstrated by encouraging feedback from the stakeholders, high students’ classifications and a steady reduction in retention. It is advocated that large portions of the reasoning behind the replanning can be extrapolated to other courses.  相似文献   
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