会展业集聚的系统动力学研究

产业集聚的影响已经引起国内外的学者的重视,会展业作为一个综合性产业,能同时带动多个经济面的发展。本文以系统动力学理论为基础,结合会展业产业集群的正负反馈特征,对会展业与基础产业、产业政策等因果关系进行了探讨。通过会展产业集聚效应的研究,利用Vensim构建系统动力学模型,分析制约会展产业集聚效应发挥的主要因素,并以上海地区会展业为例,运行模型,结果表明,模型对产业集聚效应的实际演化过程具有较高的拟合程度,并能够为区域经济管理提供有效的决策支持。     

Fast delta computations in the swap-rate market model

We develop an efficient algorithm to implement the adjoint method that computes sensitivities of an interest rate derivative to different underlying rates in the co-terminal swap-rate market model. The order of computation per step of the new method is shown to be proportional to the number of rates times the number of factors, which is the same as the order in the LIBOR market model.     

随机折现因子方法与CAPM关于风险溢价的实证比较

本文根据随机折现因子方法的基本理论,结合广义矩阵法和蒙特卡罗模拟,对随机折现因子方法和传统的CAPM对风险溢价的计算进行实证比较研究。实证结果表明,对于中小样本,随机折现因子方法比传统的CAPM方法优越。估计量较为精确,误差小;对于大容量样本,这两种方法性能接近。另外,随机折现因子方法得到Jensen＇sα均值比CAPM方法得到Jensen＇sα均值小,而且标准偏差明显较小,也从另一角度说明了随机折现因子方法的优越性。     

单信道连续波应答机距离零值仿真测试技术

本文阐述了单信道连续波应答机距离零值仿真测试方法。以及智能化高精度仿真测试仪的工作原理、设计及校准方法,并给出了测试结果。     

Impact of walking speed on tourist carrying capacity: The case of Maiji Mountain Grottoes,China

This paper analyzes the impact of walking speed on tourist carrying capacity. To do so, a combination of simulation experimentation and on-the-ground experiment is suggested to work in a study case, Maiji Mountain Grottoes, China. The simulation findings indicate that walking speed has a negative impact on tourist carrying capacity and the correlation coefficient is 0.64, for the reason that walking takes up more space. The on-the-ground experiment shows that carrying capacity is not a unified limit all over a destination, but changeable temporally and spatially, and its estimation needs to be adjusted according to the minimum area required per tourist and tourist activity. The method applied in this paper and the simulation findings can serve as a methodological tool for further research about tourist carrying capacity where the main activity of tourists is walking while watching.     

Investigating the stationarity of insurance premiums: international evidence

This article explores whether there is support for the stationarity hypotheses of life and non-life insurance premiums during the period 1979–2007 for 40 heterogeneous countries. The stationarity of insurance premiums affects insurance companies’ prediction on their future inflow of premium income, which affects the liquidity of insurance companies and their investment plans and thus is relevant to the insurers’ operation. This article employs the advanced nonlinear panel unit-root test with a sequential panel selection method to classify the entire panel into two groups: stationary countries and non-stationary countries. We apply Monte Carlo simulations to derive empirical distributions of the test, which allows us to correct for the finite-sample bias and to consider the cross-country effects. We find relatively stationary life insurance premiums in countries from the following groups: high-income, Europe, and common law origin; relatively stationary non-life insurance premiums exist in the following groups: low-income, Middle East and Africa, and common law origin. Evidence herein shows that different classifications, including income levels, geographic regions, regionally or economically integrated blocs, and legal system, affect the stationarity of life and non-life insurance premiums.     

世界连接CGE模型方法、研制与应用

随着世界经济一体化和空间经济学的日益发展,系统模型方法在国家或区域间经济联动方面的扩展和深化研究正在显现出巨大的应用价值。本文首先开发一个世界连接可计算一般均衡模型,科学揭示各经济体的运行特征,为定量剖析世界范围内各经济体的经济增长、结构变动方面提供一个系统分析框架：一方面在模型的理论框架中,分析了世界CGE模型各个模块的构建思想和对应的主要方程及其特征;另一方面建立了世界连接社会核算矩阵。然后通过动态模拟分析,检验链接模式和国家间经济联系,以及应用于各经济体政策变化的综合影响评价。     

Is There a Causal Effect of Working Part‐Time on Current and Future Wages?

In this paper, I study the causal effects of part‐time work on current and future wages. To estimate these effects, I use a random effects model with a wage equation capturing the employment history and a dynamic multinomial probit component for the choice of employment status. Exclusion restrictions from the institutional context are exploited to support identification. The results suggest that working part‐time with few hours has a large causal effect on current wages, but more extensive part‐time work does not reduce current wages. However, both types of part‐time work lead to negative long‐term wage effects.     

基于蒙特卡罗模拟的商业银行信用风险度量方法

通过与Matlab程序相结合的方式介绍了基于蒙特卡罗模拟的商业银行信用风险度量方法。该方法使在给定的置信水平下科学地估算国内商业银行的信用风险成为可能。     

Pseudolikelihood estimation of the stochastic frontier model

Stochastic frontier analysis is a popular tool to assess firm performance. Almost universally it has been applied using maximum likelihood (ML) estimation. An alternative approach, pseudolikelihood (PL) estimation, which decouples estimation of the error component structure and the production frontier, has been adopted in both the non-parametric and panel data settings. To date, no formal comparison has yet to be conducted comparing these methods in a standard, parametric cross-sectional framework. We produce a comparison of these two competing methods using Monte Carlo simulations. Our results indicate that PL estimation enjoys almost identical performance to ML estimation across a range of scenarios and performance metrics, and for certain metrics, outperforms ML estimation when the distribution of inefficiency is incorrectly specified.