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11.
I investigate the long-run relationship between corruption and innovative activity using annual data from 48 contiguous U.S. states between 1977 and 2006. Using U.S. data allows me to work with a panel long enough to exploit time series properties of the data. I use two different measures of innovative activity: one measuring the quantity and the other measuring the quality of the patents granted. I also use two different measures of corruption: one based on the number of corruption convictions, the other based on number of corruption stories covered in Associated Press news wires. Following Pedroni (1999, 2000), I estimate the cointegrating relationship between corruption and innovative activity with Fully Modified Ordinary Least Squares (FMOLS). The results indicate that corruption indeed slows down innovation in the long-run.  相似文献   
12.
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   
13.
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   
14.
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   
15.
为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。  相似文献   
16.
The relationship of plantation slavery in the Americas to economic and social development in the regions it was dominant has long been a subject of scholarly debate. The existing literature is divided into two broad interpretive models –'planter capitalism' (Fogel and Engerman, Fleisig) and the 'pre-bourgeois civilization' (Genovese, Moreno-Fraginals). While each grasps aspects of plantation slavery's dynamics, neither provides a consistent and coherent historical or theoretical account of slavery's impact on economic development because they focus on the subjective motivations of economic actors (planters or slaves) independent of their social context. Borrowing Robert Brenner's concept of 'social property relations', the article presents an alternative analysis of the dynamics of plantation slavery and their relation to economic development in the regions it dominated.  相似文献   
17.
In this paper, we argue that consideration of firm strategy can help illuminate the choices managers make between debt and equity financing. Within an industry, the form of competition that each firm chooses will determine the strategic value to the firm of maintaining financial slack. Our empirical analysis yields strong support for the proposition that financial slack should be a particularly critical strategic imperative for firms pursuing a competitive strategy premised on innovation. We also demonstrate that firms pursuing such a strategy that fail to recognize the value of financial slack are likely to perform poorly. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
18.
This article proposes a new approach to testing for the hypothesisof a single priced risk factor driving the term structure ofinterest rates. The method does not rely on any parametric specificationof the state variable dynamics or the market price of risk.It simply exploits the constraint imposed by the no-arbitragecondition on instantaneous expected bond returns. In order toachieve our goal, we develop a Kolmogorov-Smirnov test and applyit to data on Treasury bills and bonds for both the United Statesand Spain. We find that the single risk factor hypothesis cannotbe rejected for either dataset.  相似文献   
19.
对西部特色农业结构调整的思考   总被引:1,自引:0,他引:1  
西部开发战略的重要内容之一,就是开发西部特色农业,而开发西部特色农业首先要搞好农业结构调整.农业结构调整的内容有:农产品品种结构、农业生产内部结构、农产品加工转化增值和食粮主产区域结构的调整.农业结构调整也要注意一些问题,趋利避害,从实际出发,因地因时制宜,把握全局,平稳进行.  相似文献   
20.
从功能出发进行对外汉语语法教学的研究与实践   总被引:1,自引:0,他引:1  
该文系统地总结了作者进行对外汉语语法教学的实践经验——从功能出发进行对外汉语语法教学,具体从三个方面入手:一、语法教学和词汇教学相结合;二、句法结构和语义结构相结合;三、语法知识和语言环境相结合。  相似文献   
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