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61.
以中国2013年以来实行的碳排放交易试点政策作为准自然实验事件,基于2000-2017年中国30个省市的面板数据,运用双重差分法实证检验碳排放交易制度的节能减排效应及影响机制。研究发现,碳排放交易制度有利于实现中国经济“节能”与“减排”的双重目标,并通过了一系列稳健性检验;作用机制检验表明,能源效率提升和能源结构转型都是碳排放交易制度实现节能减排目标的重要路径;能源效率提升在碳排放交易制度实现“节能”和“减排”中分别发挥了10.19%和5.93%的作用,而能源结构转型分别发挥了48.87%和52.95%的作用。这意味着中国碳排放交易制度实现节能减排的主要动力来自能源结构转型,而非能源效率提升。能源结构转型涉及问题更加宏观和深层,这为中国加快推进节能减排进程,特别是完成2030年碳达峰和2060年碳中和的国际承诺提供政策启示。  相似文献   
62.
This paper proposes a multivariate distance nonlinear causality test (MDNC) using the partial distance correlation in a time series framework. Partial distance correlation as an extension of the Brownian distance correlation calculates the distance correlation between random vectors X and Y controlling for a random vector Z. Our test can detect nonlinear lagged relationships between time series, and when integrated with machine learning methods it can improve the forecasting power. We apply our method as a feature selection procedure and combine it with the support vector machine and random forests algorithms to study the forecast of the main energy financial time series (oil, coal, and natural gas futures). It shows substantial improvement in forecasting the fuel energy time series in comparison to the classical Granger causality method in time series.  相似文献   
63.
Using an extended LHARG model proposed by Majewski et al. (2015, J Econ, 187, 521–531), we derive the closed-form pricing formulas for both the Chicago Board Options Exchange VIX term structure and VIX futures with different maturities. Our empirical results suggest that the quarterly and yearly components of lagged realized volatility should be added into the model to capture the long-term volatility dynamics. By using the realized volatility based on high-frequency data, the proposed model provides superior pricing performance compared with the classic Heston–Nandi GARCH model under a variance-dependent pricing kernel, both in-sample and out-of-sample. The improvement is more pronounced during high volatility periods.  相似文献   
64.
吴丹  胡晶 《科技进步与对策》2018,35(20):128-136
科技创新规模扩张和科技创新效率提升是增强国家科技创新能力的两条关键途径。基于现有研究鲜有结合科技创新规模和科技创新效率开展国家科技创新能力评价的现状,采用因子分析法,系统筛选国家科技创新规模影响因素,并结合科技创新效率影响因素,完善国家科技创新能力评价指标体系,通过构建DEA Malmquist指数模型,评价不同时期国家科技创新效率变化指数,以及中国与全球10个国家科技创新能力的时空差异性。研究表明,R&D投入强度、R&D研究人员、专利申请量、科技期刊文章数、高科技产品出口额占制成品出口总额的百分比、科技创新效率是影响国家科技创新能力的关键指标;1991-2014年中国科技创新能力水平呈指数增长态势,有力提升了国家科技实力;全球10个国家科技创新能力水平除日本出现一定波动外,其余九国整体呈小幅递增态势。  相似文献   
65.
World tourism cities perform multiple functions and exhibit various characteristics that influence tourism development within their boundaries. They are the main gateway for tourists visiting a country and their success has a direct impact on the visitor economy of that destination. London, the focus of this research, has been one of the world’s top tourism cities for many years, and a key gateway for domestic and international visitors. But despite the important role tourism plays in the economy of the city, there is limited research on the development of this activity in the capital. Using London as an exploratory case study, this paper contributes to better understanding the challenges faced by policy makers when planning and managing tourism in world cities. The adopted research method offers the advantage of gathering insightful information using multiple data collection techniques. Examining this new evidence contributes to expanding the knowledge on the particularities of tourism development in one of the top world cities, which could help policy makers in their efforts to better prepare for potential challenges faced by these complex but important destinations.  相似文献   
66.
This study investigates the importance of mindfulness‐based organization systems and policies on the organization's continuous efforts to become a greener company. The study is devised as a pooled cross‐sectional time series analysis of productivity in energy consumption, water utilization, and waste generation and recycling of U.S. companies. The data set taken from U.S. Newsweek 500 recorded 600 companies dispersed into 63 industries during the period of 2012–2014 and provided 1,498 company–industry–year observations. The study found that systems and policies (e.g., deployment of third‐party auditors for its environmental metrics report; linkage of the remuneration of company's senior executive team with the achievement of environmental performance targets; and establishment of a committee at the Board of Directors' level whose mandate includes sustainability of the company in environment‐ and resource‐related matters) connect the company's mindfulness to its effort in improving the environmental quality through the company's productivity in energy consumption, water utilization, and waste generation and recycling. The relationships are positive and significant. Also, systems and policies serve as a motivator for the firm to continue to improve upon the current achievements. The study emphasizes the importance of translating organizational and individual mindfulness into organization policies and systems in order to motivate the organization to continuously improve its productivity in energy consumption, water utilization, and waste generation and recycling leading to improvements in environmental quality.  相似文献   
67.
Following the approach of interpolation, this paper proposes the multiple exponential decay model to fit yield curves for both the U.S. TIPS market and the conventional Treasury security market. Several estimation methods, including the unconstrained/constrained nonlinear minimization, quadratic programming, and the iterative linear least squares, are applied to estimate the unknown parameters according to different curve‐fitting purposes. Comparisons between the proposed model and the alternatives show that the multiple exponential decay successfully (1) adapts to a variety of shapes associated with yield curves, (2) (partially) keeps in line with the economic interpretations of Nelson–Siegel summarized by Diebold and Li ( 2006 ), and (3) dominates the competing models in curve‐fitting performance measured by mean fitted‐price errors over the sample period. In addition, the exact specification of a nonparametric interpolation model is pinned down by applying three statistical tools, which enable us to jointly take into account validity, optimality, and parsimoniousness of the proposed model.  相似文献   
68.
In the retail industry, backroom inventories are typically associated with higher labor costs and greater operational complexity. Thus, retailers look for ways to eliminate backroom inventories. A heuristic used for this purpose is the pack‐and‐a‐half rule which suggests that the shelf space allocated for a product should be at least 50% larger than the case pack quantity in which the product is delivered. Despite its popularity among retailers, the pack‐and‐a‐half rule has been ignored in the academic literature. We introduce the pack‐and‐a‐half rule, assess its impact on a retailer's profits, identify cost, demand, and product characteristics driving this impact, and propose a modification. Based on an analysis of data obtained from a retailer on 1,986 SKUs in 20 categories, we find that the pack‐and‐a‐half rule decreases a retailer's profits, on average, by 10% when applied uniformly across all SKUs. Further, this decrease is significantly affected by product depth, product width, demand elasticity, case pack quantity, and inventory carrying cost. Finally, we develop a set of modifications based on these variables where the pack‐and‐a‐half rule is applied selectively and in a stepwise fashion. These modifications limit the decrease in a retailer's profits to a range between 6% and 7%.  相似文献   
69.
Mobile channel additions have been shown to increase consumer-brand relationships, brand satisfaction towards and overall purchasing from a retailer, but what is less apparent is whether shareholders are fully rewarded for retailers’ mobile channel additions. Results from an event study on 115 announcements relating to mobile app additions of publicly traded U.S. retail firms between 2009 and 2016 indicate that the stock market responds generally positively to mobile app additions, but specifically to the two mobile app addition types. Stock market responses to search-related and purchase-related app additions are moderated by firm size, product category, and target customer age. For announcements of search-related apps, the market responds more positively to product retailers than to service retailers, and to small firms than large ones. For announcements of purchase-related apps, the market responds less positively to firms that target younger customers than firms who do not especially target them.  相似文献   
70.
Human rights (HR) and corporate social responsibility (CSR) are both fields of knowledge and research that have been shaped by, and examine, the role of multi-national enterprises in society. Whilst scholars have highlighted the overlapping nature of CSR and HR, our understanding of this relationship within business practice remains vague and under-researched. To explore the interface between CSR and HR, this paper presents empirical data from a qualitative study involving 22 international businesses based in the UK. Through an analysis based on sensemaking, the paper examines how and where CSR and HR overlap, contrast and shape one another, and the role that companies’ international operations has on this relationship. The findings reveal a complex and multi-layered relationship between the two, and concludes that in contrast to management theory, companies have bridged the ‘great divide’ in varying degrees most notably in their implementation strategies.  相似文献   
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