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1.
This study addresses current gaps in the empirical literature regarding the effect of diplomatic representation on trade using a panel data set for 100 countries with 5‐year interval data from 1985 to 2005 and four‐digit level industry data. The results indicate that the effect of diplomatic representation on exports in differentiated goods is positive and significant and larger than on exports in homogeneous goods on average, but not statistically different from it. Furthermore, diplomatic representation only increases trade along the extensive margin and not along the intensive margin. The results indicate that diplomatic representation is effective in performing its function as a network search intermediary and that it is a useful policy tool to alleviate market failure.  相似文献   
2.
离散小波变换(Discrete Wavelet Transform,DWT)通常用于图像的表示。然而,对于具有不规则形状边缘的图像,尤其是对于纹理和细节信息较多的遥感图像,DWT却很难有效表示,进而影响后续去噪效果。针对该问题,提出了一种基于图形小波变换(Graphic Wavelet Transform,GWT)的图像去噪方法。首先,将图像表示为图形信号,并通过该图形信号的谱表示构造相应的变换矩阵;然后,设计了一种改进自适应阈值的图像去噪方法,在GWT变换域内对图像去噪。实验结果表明,与常用的图像去噪方法相比,所提算法能够提供更好的图像主观质量。采用均方根误差(Root Mean Square Error,RMSE)和峰值信噪比(Peak Signal-to-Noise Ratio,PSNR)作为客观指标,结果表明,采用所提方法得到的重建图像客观质量更优。  相似文献   
3.
本文试图探析在中国地方人大中是否存在地域性代表及其相关因素。通过收集和分析2017年国内五省市人大收到的近四千条代表建议,发现在地方人大代表的履职行为中,一定范围内存在从整体资源中为选区争取利益的现象。进一步回归分析的结果显示:来自经济发展水平相对较低的地区的代表,更倾向于提出地域性建议;由代表联名提出的建议更可能是地域性建议;担任地方党政领导职务的省市人大代表,在提出建议时更倾向于提出地域性建议。上述实证发现对中国地方人大地域性代表的实现机制提供了初步启发性证据,也有助于丰富我们对非竞选体制下的政治代表性和回应性机制的理解。  相似文献   
4.
This paper studies the role of gender equality in female directors’ efficacy and its subsequent effects on firms. Female directors in more gender equal societies should possess greater skills and exert more influence due to better access to educational/professional opportunities and more amicable boardroom dynamics. Therefore, we hypothesize that gender equality serves as an important moderator in the relation between female board representation and firm outcomes. Using a multi-national panel comprising 1986 public firms from 24 countries or areas spanning from 2007 to 2016, we obtain results that firms with higher female board representation exhibit higher overall performance, less earnings management, and less excessive risk taking, in which all three relations are stronger in countries with greater gender equality. Taken together, our paper implies that the impact of female directors on firm outcomes depends on a country's overall level of gender equality.  相似文献   
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6.
We extend some results of the Itô calculus to functionals of the current path of a process to reflect the fact that often the impact of randomness is cumulative and depends on the history of the process, not merely on its current value. We express the differential of the functional in terms of adequately defined partial derivatives to obtain an Itô formula. We develop an extension of the Feynman-Kac formula to the functional case and an explicit expression of the integrand in the Martingale Representation Theorem. We establish that under certain conditions, even path dependent options prices satisfy a partial differential equation in a local sense. We exploit this fact to find an expression of the price difference between two models and compute variational derivatives with respect to the volatility surface.  相似文献   
7.
This article excavates the debate that unfolded during the 1980s between Jacques Rancière and Pierre Bourdieu to shed light on the theoretical divide that still cuts across the field of urban studies today. Looking at contemporary Rancièrian scholarship through a Bourdieusian lens, it points to their main theoretical shortcomings and reasserts the value of relational, field‐based and empirically grounded approaches to urban politics. At the same time, this article engages seriously Rancière's critique of Bourdieu's failure to account for space in order to question the territoriality inherent to the notion of field. We put this theoretical discussion to the test of Lagos's garbage. Drawing on an ethnographic study conducted in Lagos from 2015 to 2016, we propose analyzing the process of spatialization of the field of local representation by looking at the ways solid waste—here conceived as a political opportunity—is mobilized by different actors. We argue that the deployment of a waste infrastructure in Lagos is congruent with a relative disinvestment in practices of territorial control that reshapes the structure of local representation, reconfiguring the ‘stage’ on which politics is played out in the Nigerian metropolis.  相似文献   
8.
This article reviews the literature of commercial diplomacy during the period 1960–2014 from a management angle and is organized around four major themes: (1) government’s export/trade promotion function; (2) institutional/organizational arrangements; (3) managerial roles and activities; and (4) interaction between commercial diplomats and businesses. A complementary quantitative analysis tracing current research trends reveals the emergence of relevant publications at the end of the 1970s and a real increase after 2000. It also confirms the relative scarcity of commercial diplomacy literature focusing on the business and management dimension. Gaps in current literature are identified, and suggestions for further research are presented.  相似文献   
9.
Mijatovi? and Pistorius proposed an efficient Markov chain approximation method for pricing European and barrier options in general one‐dimensional Markovian models. However, sharp convergence rates of this method for realistic financial payoffs, which are nonsmooth, are rarely available. In this paper, we solve this problem for general one‐dimensional diffusion models, which play a fundamental role in financial applications. For such models, the Markov chain approximation method is equivalent to the method of lines using the central difference. Our analysis is based on the spectral representation of the exact solution and the approximate solution. By establishing the convergence rate for the eigenvalues and the eigenfunctions, we obtain sharp convergence rates for the transition density and the price of options with nonsmooth payoffs. In particular, we show that for call‐/put‐type payoffs, convergence is second order, while for digital‐type payoffs, convergence is generally only first order. Furthermore, we provide theoretical justification for two well‐known smoothing techniques that can restore second‐order convergence for digital‐type payoffs and explain oscillations observed in the convergence for options with nonsmooth payoffs. As an extension, we also establish sharp convergence rates for European options for a rich class of Markovian jump models constructed from diffusions via subordination. The theoretical estimates are confirmed using numerical examples.  相似文献   
10.
This paper surveys the conditions under which it is possible to represent a continuous preference ordering using utility functions. We start with a historical perspective on the notions of utility and preferences, continue by defining the mathematical concepts employed in this literature, and then list several key contributions to the topic of representability. These contributions concern both the preference orderings and the spaces where they are defined. For any continuous preference ordering, we show the need for separability and the sufficiency of connectedness and separability, or second countability, of the space where it is defined. We emphasize the need for separability by showing that in any nonseparable metric space, there are continuous preference orderings without utility representation. However, by reinforcing connectedness, we show that countably boundedness of the preference ordering is a necessary and sufficient condition for the existence of a (continuous) utility representation. Finally, we discuss the special case of strictly monotonic preferences.  相似文献   
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