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51.
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   
52.
为了充分利用各种空间设施资源,提升天基信息网络覆盖与传输能力,分别从天基信息网络体系架构和逻辑功能架构角度进行了系统性设计。与以往天基网络的设计不同,该设计更注重各类卫星网络的深度融合应用,为此将网络虚拟化技术引入天基卫星网络。同时,还提出了解决新架构下卫星组网难题的方法,将电磁涡旋、卫星灵活载荷和边缘计算技术设计到天基网络。仿真表明,所提出的架构能有效提升频谱利用率和减少卫星网络信令开销。  相似文献   
53.
隔代抚育会对延迟退休年龄政策在促进劳动力供给上产生挤出效应。为了对此进行验证,本文在工资收入随机性的假定及延迟退休5年的情景下,模拟了面临孙辈照护需求的女性临近退休者提前退休所产生的福利变化。进一步,本文采用CHIP和CHARLS的微观调查数据,对不同群组的收入增长率和收入风险进行了估计,继而分析了当面临孙辈照护需求时这些收入特征对退休决策者制度退休和退休后劳动参与抉择产生的影响。总体上,在延迟退休年龄政策下,隔代抚育将对女性劳动力供给产生挤出效应。当面临孙辈照护需求时,女性临近退休者的制度退休抉择主要受自身收入增长率和收入风险的影响,收入增长率越低,或收入风险越高,她们提前退休的意愿就越强烈;制度退休后的劳动参与则更多地受子女收入增长率的影响,子女收入增长率越高,劳动参与的概率越低。  相似文献   
54.
I study the implications for central bank discount window stigma of a workhorse model of adverse selection in financial markets. In the model, firms (banks) need to borrow to finance a productive project. There is limited liability and firms have private information about their ability to repay their debts, which gives rise to the possibility of adverse selection. The central bank can ameliorate the impact of adverse selection by lending to firms. Discount window borrowing is observable and it may be taken as a signal of firms' credit worthiness. Under some conditions, firms borrowing from the discount window may pay higher interest rates to borrow in the market, a phenomenon often associated with the presence of stigma. I discuss these and other outcomes in detail and what they suggest about the relevance of stigma as an empirical phenomenon.  相似文献   
55.
高科技社会衍生“人为风险”,西方发达高科技国家倡导新型风险沟通,而后发场域由于系统落差,呈现出迟滞型风险沟通。通过构建全球化高科技风险社会、全球本地化风险沟通的新分析框架,发现高科技社会我国风险沟通面临着风险的社会放大、气泡结构、路径互动阙如、手段叠加、目标战略缺失、过程碎片化等迟滞困境。通过创新理念、吸纳型风险沟通、复合式路径、平衡化手段、连续统、政府学习和政府职能的“七位一体”再造,可有效重塑高科技社会我国风险沟通,推进国家风险治理体系和治理能力现代化。  相似文献   
56.
我国粮食产后损失情况概述   总被引:1,自引:0,他引:1  
本文系统分析了粮食产后各环节损失的原因及损失量,针对相关粮食损失原因及状况,提出了减少粮食产后损失的措施及建议,以期为我国实现节粮减损提供支持。  相似文献   
57.
PSM has played an important role in the initial mitigation of risks caused by the COVID-19 pandemic. We explore the nature and scope of this role and develop a roadmap for PSM contributions towards greater supply chain resilience. We find that the role of PSM is (1) multidimensional; responding to supply risks but also to demand and logistics risks, (2) counter to game theory; collaboration increased instead of decrease, (3) multi-stage; beyond the initial response the hardest change efforts are still ahead. The pandemic is accelerating the journey towards future-proof PSM but not necessarily revolutionizing the future of PSM.  相似文献   
58.
Research Summary: This study addresses a theoretical dilemma regarding how alliance network constraint (reflected by network cohesion) affects a firm’s alliance formation with new partners. Using a network pluralism approach, we separate a firm’s ego alliance network into two activity‐based networks—an exploratory network and an exploitative network—based on the primary value chain activity involved in each alliance. We argue that the cohesion of exploratory or exploitative networks has an inverted U‐shaped effect on the addition of new partners in the same activity‐based network, and a positive effect on the addition of new partners in the other network. Results based on data from the biotechnology industry largely support our predictions with one exception. Our study contributes to both scholarly understanding of network embeddedness and alliance practice. Managerial Summary: The structure of firms’ ongoing alliance networks may have paradoxical implications for their efforts to search for and form alliance with new partners. That is, when a firm’s alliance partners are tightly connected with each other, the cohesive network tends to both encourage and impede the focal firm to add new partners. We resolve this dilemma by showing that when a firm is deeply entrenched in a cohesive alliance network conducting a certain type of activities (e.g., R&D activities), it may not easily add new R&D alliance partners. However, it may still be able to escape from the cohesive R&D alliance network by seeking new partners conducting other activities (e.g., manufacturing activities).  相似文献   
59.
Tolina Fufa 《Applied economics》2018,50(60):6512-6528
To study the role of financial development in economic growth, we apply an array of convergence tests designed to capture nonlinear transitional dynamics to real outputs per capita. Strong evidence of multiple convergence clubs is observed, implying that the clubs are formed based on the initial level of real output per capita and average growth rate. Our empirical results show that the stage of economic growth of each country plays an important role for the composition of the convergence clubs. Furthermore, financial development emerges to be a significant determinant, albeit plays differently in the economic growth of each convergence club.  相似文献   
60.
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   
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