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21.
我国大麦价格波动特征及其影响因素分析   总被引:1,自引:0,他引:1  
[目的]大麦价格剧烈波动会直接影响大麦种植户的生产积极性和大麦产业的平稳发展,研究大麦价格波动特征及其影响因素,有助于提升大麦产业链相关主体识别和应对市场风险的能力,促进大麦产业的健康发展。[方法]文章先采用HP滤波法和ARCH类模型分析了2011年4月至2017年2月我国大麦价格波动特征,然后采用脉冲响应函数分析了我国大麦价格波动影响因素。[结果]我国大麦价格波动存在明显的季节性和周期性,样本期内总体上呈现逐渐下降趋势;我国大麦价格具有显著的波动集聚性,我国大麦价格具有显著的不对称性;在该文选择的影响因素中,大麦进口量和国际大麦价格是影响我国大麦价格波动的主要因素。[结论]该文提出必须保障并提高国内大麦合理产能、完善大麦价格监测预警体系、加强国内大麦进口企业整合和推动大麦进口来源多元化的政策建议。  相似文献   
22.
Distance functions are increasingly being augmented, with environmental goods treated as conventional outputs. A common approach to evaluate the opportunity cost of providing an environmental good is the exploitation of the distance function's dual relationship to the value function. This implies that the opportunity cost is assumed to be non‐negative. This approach also requires a convex technology set. Focusing on crop diversification for a balanced sample of 44 cereal farms in the East of England for the years 2007–2013, this paper develops a novel opportunity cost measure that does not depend on these strong assumptions. We find that the opportunity cost of crop diversification is negative for most farms.  相似文献   
23.
The two dividends in the double‐dividend hypothesis are assumed to be independent. This assumption can be misleading when it comes to formulating policy. I construct a model where the pollution tax rate is voted for by heterogeneous people. In addition to the revenue‐recycling effect, the equilibrium pollution tax rate depends on two opposite forces: the tax‐cutting effect and the profit effect. The two forces show that an instrument that exploits a greater revenue‐recycling effect can cause a more severe environmental deterioration, thereby resulting in the infeasibility of the hypothesis. The introduction of the interdependence between the two dividends can also mean that non‐revenue‐raising instruments are more efficient than revenue‐raising instruments.  相似文献   
24.
This paper examines the cumulative market reaction to the events related to deferral of internal control audit requirement under the Sarbanes-Oxley Act of 2002 and its elimination under the Dodd-Frank Act of 2010 for nonaccelerated filers (small firms). We document that small firms experienced negative cumulative abnormal returns around these events; and the differences between the cumulative abnormal returns for small firms and the two control groups (accelerated and large accelerated filers) were negative and significant at the 1% level. These results support the notion that market participants value the reliability of financial information irrespective of the firm size. Within the small firms, we find no firm characteristic significantly explains the market reaction to the events considered. That is, all small firms lost market value in reaction to the events that delayed and eliminated their internal control audit requirement.  相似文献   
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26.
Since the end of the Bretton Woods era, the world has operated on a de facto system of free‐floating exchange rates, with the US dollar as the dominant international currency. The system, characterized by large pro‐cyclical capital flows and chronic imbalances, is inherently unstable, and has contributed to repeated crises, recessions and geopolitical tensions. One potentially “least‐difficult” line of reform would be to allow the evolution of a multi‐currency system, underpinned by an expanded role for Special Drawing Rights (SDRs). Attempts to promote wider use of the SDR have foundered on the liquidity premium. However, for Chinese corporations and institutions, at present restricted in their capital account activities, the SDR liquidity premium would appear less daunting. The Chinese authorities could provide policy encouragement for the use of SDRs by their institutions. This initiative, supported by China's Special Administrative Region Hong Kong, would kick‐start an international SDR ecosystem, and encourage even broader use of SDRs, to the benefit of international monetary stability.  相似文献   
27.
在雷达目标跟踪中,系统量测信息通常在球坐标系下获得。为了采用经典卡尔曼滤波算法实现有效目标跟踪,通常采用量测转换方法将非线性量测信息转换到直角坐标系中。针对传统量测转换方法基于量测值计算转换误差统计特性而导致的估计结果有偏问题,提出了一种基于预测值的量测转换方法,并将其与卡尔曼滤波算法相结合,获得了一种基于预测值量测转换的卡尔曼滤波跟踪算法。仿真结果表明,与现有的基于量测转换的卡尔曼滤波算法相比,该算法能在不提高运算量的情况下有效改善目标跟踪效果,跟踪精度提升约20%。  相似文献   
28.
围绕深化小型水利工程管理体制改革和管护机制创新,以推进供给侧结构性改革为主线,分析当前我国小型水利工程管理能力面临的新形势,结合小型水利工程管理现状及存在的主要问题,探讨供给侧结构性改革中如何加强工程管理单位能力建设,并从供给侧结构性改革角度,提出创新管护模式、拓宽经费渠道、加强农民用水合作组织建设、建立考核评价机制等建议。  相似文献   
29.
A fundamental policy in European broadband regulation is unbundled access to the local loop of the incumbent telephone company. We present comparative static results that show as the access price decreases, the retail price decreases, the variety of plans offered by Internet service providers increases and the quantity of each variety increases when a threshold condition is met. Using data from 18 European countries from 2006 to 2012, we find empirical support for these results when Internet product variety is measured by variation in download speeds.  相似文献   
30.
The Producer Price Index (PPI) for the U.S. suggests that semiconductor prices have barely been falling in recent years, a dramatic contrast to the rapid declines reported from the mid‐1980s to the early 2000s. This slowdown in the rate of decline is puzzling in light of evidence that the performance of microprocessor units (MPUs) has continued to improve at a rapid pace. Over the course of the 2000s, the MPU prices posted by Intel, the dominant producer of MPUs, became much stickier over the chips' life cycle. As a result of this change, we argue that the matched‐model methodology used in the PPI for MPUs likely started to be biased after the early 2000s and that hedonic indexes can provide a more accurate measure of price change since then. MPU prices fell rapidly through 2004 on every price measure we present, with the PPI declining at an even quicker pace than the hedonic indexes. However, from 2004 to 2009, our preferred hedonic index fell faster than the PPI, and from 2009 to 2013 the gap widened further, with our preferred index falling at an average annual rate of 42 percent, while the PPI declined at only a 6 percent rate. Given that MPUs currently represent about half of U.S. shipments of semiconductors, this difference has important implications for gauging the rate of innovation in the semiconductor sector.  相似文献   
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