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61.
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   
62.
We tested relationships between employee quit rates and two bundles of human resource (HR) practices that reflect the different interests of the two parties involved in the employment relationship. To understand the boundary conditions for these effects, we examined an external contingency proposed to influence the exchange-based effects of HR practices on subsequent quit rates – the local industry-specific unemployment rate – and an internal contingency proposed to shape employees’ conceptualization of their exchange relationship – their employment status (i.e. full-time, part-time and temporary employment). Analyses of lagged data from over 200 Canadian establishments show that inducement HR practices (e.g. extensive benefits) and performance expectation HR practices (e.g. performance-based bonuses) had different effects on quit rates, and the former effect was moderated by unemployment rate. The effects of HR practices on quit rates did not differ between FT and PT employees, but a different pattern of main and interactive effects was found among temporary workers. These findings suggest that employees’ exchange-based decisions to leave may be less affected by the number of hours they expect to work each week, and more by the number of weeks they expect to work.  相似文献   
63.
Declining unionization rates and job polarization are two important labor market developments of recent decades. A large body of literature has analyzed these phenomena separately, but little has been done to see whether there is a link between them. We employ a macroeconomic model for a small open economy with a large input–output core to analyze how deunionization may cause job polarization. Our analysis shows that medium-skilled workers are negatively affected by deunionization, mainly as a result of the heterogeneity of the elasticities of substitution between different types of labor. While the elasticities of substitution between high- and medium-skilled labor are relatively low, the elasticities of substitution between medium- and low-skilled are relatively high. As a result, when deunionization leads to increased wage dispersion, we find that demand for low-skilled increases at the expense of medium-skilled labor, thus yielding a more polarized labor market.  相似文献   
64.
The Chinese high-tech industry has developed greatly since the beginning of China's “National High-tech R&D (863) Program” and “China Torch Program”. This paper introduces a conceptual model extended from the innovation value chain model to simultaneously estimate the R&D and commercialization efficiencies for the high-tech industries of 29 provincial-level regions in China. To match reality, a network DEA incorporating both shared inputs and additional intermediate inputs is constructed to open the “black box” view of decision making units used in single-stage DEA. This study is the first attempt to link the R&D and commercialization with a solid theoretical foundation and feasible mathematical methods. The empirical findings show that most of the 29 regions have low efficiency in the commercialization sub-process compared to the R&D sub-process, although there are regional differences in China's high-tech industry. Pearson correlation shows that the R&D sub-process is not closely correlated to the commercialization sub-process in terms of efficiency. Our analysis can provide information for the formulation of policies to achieve high innovation efficiency.  相似文献   
65.
新制度经济学视角下的中国农地制度变迁:回顾与展望   总被引:1,自引:0,他引:1  
研究目的:分析总结中国农地制度变迁的路径特征、决定条件和影响因素,并展望进一步研究方向。研究方法:文献分析法。研究结果:(1)改革开放以来的中国农地制度变迁呈现出一个较清晰的路径,即改革始终沿着市场取向、明晰产权、稳定地权的方向演进;(2)农地使用权制度改革的成功源于诱致性变迁与强制性变迁的结合,即弹性的中央政策制定、渐进式的地方实施以及具有学习效应的农户认知三者的有机互动,并体现出制度变迁的"共生演化"特征及其蕴含的"适应性效率";(3)新制度经济学是解释中国经济改革和农地制度变迁的有效工具,然而由于经典的新制度经济学本质上的静态性以及国家理论的缺乏,难以对现实世界的各类制度变迁给出一般化的解释。研究结论:基于经典的新制度经济学,进一步整合行为经济学、机制设计理论、演化博弈论等理论工具,超越"强制性—诱致性变迁"二分法,构建一个真正动态的制度变迁模型是一个重要研究方向。  相似文献   
66.
Differences among bidder type-specific outcomes of asset sales are theoretically related to differences in bidders’ valuations and participation. The lead application to quantify these relations is takeover auctions: bidders are classified into strategic and financial, and bids are available. I structurally estimate valuations from all bids. The positive difference in premiums between strategic and financial acquirers is driven by the difference in dispersions of valuations (e.g., strategic bidders’ synergies are more dispersed) and the set of auction participants. The difference in average valuations is relatively unimportant. My approach can help explain outcomes of asset sales, even in settings with limited bidder data.  相似文献   
67.
研究目的:剖析农村土地制度和农业经营制度的关系,为完善农村基本经营制度提供参考。研究方法:比较分析法、文献研究法。研究结果:新中国成立70年来,农村基本经营制度先后历经新中国成立初期的"农民所有、家庭经营"、改革开放前期的"集体所有、集体经营"到改革开放后期的"集体所有、均田承包、家庭经营",再到现阶段的"集体所有、均田承包和多元经营"4个阶段。在这个过程当中,农村基本经营制度既遵循人口与土地关系、生存与发展关系以及政府与市场关系的大逻辑,又遵循着农村土地制度的"产权逻辑"、农业经营制度的"生产逻辑"等小逻辑。研究结论:为深化农村基本经营制度变革,需加强农村土地制度与农业经营制度联动改革的制度设计,发挥要素、组织和制度的作用,发展多种形式的适度规模经营,实现小农户与现代农业发展的有机衔接。  相似文献   
68.
粮食主产区耕地健康产能评价 ——以河南省温县为例   总被引:6,自引:0,他引:6  
研究目的:探寻适合中国新时代耕地产能评价的新理论与方法,界定耕地健康产能内涵,构建评价指标体系,并应用河南省温县验证。研究方法:基于"需求—功能—维度—要素—指标"理论框架,构建耕地健康产能评价指标体系,运用综合算法、"1+X"累加模型法、图层叠加法定量评价耕地健康产能。研究结果:(1)温县耕地产能和耕地健康诊断结果地域分异特征明显,以青峰岭为界,北部耕地产能和健康状况较南部好;(2)耕地健康产能整体状况良好,乡镇间差异明显;(3)耕地健康产能结果更多取决于耕地健康诊断,主要受耕地生产环境和耕地系统弹性影响。研究结论:耕地健康产能评价指标体系和评价方法有应用性。  相似文献   
69.
The “50/50”, or the shared management international joint venture (shared IJV) remains a popular and yet challenging control structure to govern IJVs. The purpose of this study is to understand the post-formation management of shared IJVs, specifically the relationship between shared structure, relational conditions and management of post-formation challenges. Our evidence is based on 26 in-depth interviews across four cases of shared IJVs between British multinationals and Asian companies. Our findings indicate that the highly integrative nature of shared IJVs, including high operational interdependence and shared decision-making, encourages partners to work closely together, communicate frequently and intensely and exchange personnel. Although share management can lead to inter-partner conflicts, the equal investment and mutual responsibility partly provides partners with motivation and opportunities to learn about each other, to better implement the control structure, to build trust, and to commit to the venture and partner. These relational conditions facilitated the successful management of post-formation challenges such as diversity related conflicts and macro volatility.  相似文献   
70.
[目的]通过分析城镇化时空格局及其驱动力用来表现河南省城镇化近10年状态,并通过驱动力分析其主要影响因素。[方法]文章选取人均GDP、财政收入、第三产业生产总值、全社会固定资产投资、在岗职工平均工资、各市参加医疗保险人口、天然气用气人口、各市普通高中毕业生、废水排放量、生活垃圾处理量、固体废物处理量、道路清扫保洁面积等12个指标构建综合指标体系,运用SPSS因子分析确定权重,测算2005~2015年河南省城镇化发展水平并分析其时空演变特征,在此基础上利用灰色关联度分析城镇化发展驱动力。[结果]河南省城镇化水平在时间维度上呈上升趋势,空间上表现为高城镇化水平集中在河南省西北部地区,有向东北部发展的趋势;低水平城镇化地区集中在河南省中南部地区且数量逐渐减少;中等水平的城镇化地区集中在河南省周边的地级市,数量逐渐增多,且有向高等城镇化水平发展的趋势;就驱动力影响力而言,市场机制高居第一,其次是政府作用、自身发展、外商投资。[结论]河南省城镇化水平空间差异显著,并受多种驱动力共同影响。  相似文献   
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