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71.
The general consensus in the volatility forecasting literature is that high-frequency volatility models outperform low-frequency volatility models. However, such a conclusion is reached when low-frequency volatility models are estimated from daily returns. Instead, we study this question considering daily, low-frequency volatility estimators based on open, high, low, and close daily prices. Our data sample consists of 18 stock market indices. We find that high-frequency volatility models tend to outperform low-frequency volatility models only for short-term forecasts. As the forecast horizon increases (up to one month), the difference in forecast accuracy becomes statistically indistinguishable for most market indices. To evaluate the practical implications of our results, we study a simple asset allocation problem. The results reveal that asset allocation based on high-frequency volatility model forecasts does not outperform asset allocation based on low-frequency volatility model forecasts.  相似文献   
72.
The credit risk contagion of Internet peer-to-peer (P2P) lending platforms is an important part of Internet financial risk management and supervision. This study analyzes the contagion path of credit risk in Internet P2P lending. Based on complex network theory and the theory of infectious disease dynamics, the characteristics of Internet P2P lending development are combined to construct a SEIR model of credit risk transmission among Internet P2P lending platforms with time lag, and the robustness of the model is analyzed and proven. The influence of platform correlations, the susceptible immune rate, the platform elimination rate, contagion latency, the saturation coefficient, and the susceptibility input rate on credit risk contagion behavior among Internet P2P lending platforms is analyzed, using the equilibrium point and threshold value. The impact of each variable is analyzed by simulation. Corresponding countermeasures and suggestions are proposed to prevent and control credit risk contagion among these platforms.  相似文献   
73.
王勉  黄颖  杨颖 《科技和产业》2019,19(4):92-98
互联网经济快速发展,基于互联网平台的企业创新行为具有鲜明的特色。纵向研究了三家企业的创新过程,发现互联网环境下,企业商业模式创新有三个特点:以客户为中心的战略准则,价值创造由企业转向客户;企业打破边界,加强合作伙伴之间的协同和柔性,大幅提高创新效率;企业提高管理不确定的能力,领导者、企业文化、管理模式帮助企业应对不确定性。同时,提出当前创新模式存在核心技术缺乏、生产端缺乏创新的潜在风险,并提出创新发展的建议:加强生产端互联网的建设,提高创新质量;深化完善商业生态系统建设,提高商业系统整体的创新能力。  相似文献   
74.
Despite the heightened popularity of entrepreneurship education, there remain open questions regarding best practices in co-curricular programs. Using the theory of planned behavior, the authors examine how students’ intention is shaped to increase the likelihood of participation in entrepreneurship co-curricular programs. To the best of the authors’ knowledge, this study is the first to examine the relation between entrepreneurial identity and entrepreneurial intention theory. They find the popular personality trait, openness, is related to ambition, which reveals the interaction between personal elements (personality/identity) and contextual elements (aspirations to success/intention), a novel finding in the literature. This further illustrates the interconnectedness between the theory of planned behavior and the entrepreneurial event model  相似文献   
75.
ABSTRACT

In this paper, Weaver’s six-stage indigenous tourism model is applied to the Lacandon Maya (Hach Winik) of Chiapas, Mexico. Based on a comprehensive review of the anthropological and historical literature on this indigenous group, combined with longitudinal ethnographic and collaborative research performed with tourism entrepreneurs, the Lacandon tourism experience is assessed from the pre-European period until present. By analysing a case study of indigenous tourism in Mexico, a developing country in another geographical region and with a different colonial past, this work supplements Weavers’ perspective. The results show that the fourth and fifth stages of Weaver’s model coincide in this case study, while the sixth stage is still incomplete. Although the Lacandon case has its peculiarities and bearing in mind that several different factors should be considered in the Latin American context, the model proves to be an interesting tool for indigenous tourism analysis in developing countries.  相似文献   
76.
This study proposes a hybrid information approach to predict corporate credit risk. In contrast to the previous literature that debates which credit risk model is the best, we pool information from a diverse set of structural and reduced‐form models to produce a model combination based on credit risk prediction. Compared with each single model, the pooled strategies yield consistently lower average risk prediction errors over time. We also find that while the reduced‐form models contribute more in the pooled strategies for speculative‐grade names and longer maturities, the structural models have higher weights for shorter maturities and investment grade names.  相似文献   
77.
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   
78.
为了解决同时含有随机因素和灰色因素的不确定规划问题,通过结合区间灰数所属区间两个端点的随机性,给出随机区间灰数和随机区间灰函数的定义,提出了随机灰规划模型。通过综合效应函数理论用随机变量期望值和方差综合量化表示灰数所属区间的两个端点值。应用该理论对综合量化后的两个端点值继续进行综合量化,从而将随机灰规划转化为确定型规划问题。应用遗传算法进行求解。通过综合效应函数的理念,综合随机变量的期望和方差,同时综合区间灰数的区间因素,将随机灰规划数学模型转化为确定型规划模型即基于效应的随机灰规划模型。通过选取不同的综合效应函数,得到了关于不同决策意识下的随机灰规划的最优解。这个方法可为决策者进行不确定决策提供参考。  相似文献   
79.
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   
80.
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   
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