Regression Analysis under Probabilistic Multi‐Linkage

Linkage errors can occur when probability‐based methods are used to link records from two distinct data sets corresponding to the same target population. Current approaches to modifying standard methods of regression analysis to allow for these errors only deal with the case of two linked data sets and assume that the linkage process is complete, that is, all records on the two data sets are linked. This study extends these ideas to accommodate the situation when more than two data sets are probabilistically linked and the linkage is incomplete.     

一类非单调二元算子方程解的存在唯一性

利用锥理论和非对称迭代方法,讨论了一类非单调二元算子方程解的存在唯一性,给出了迭代序列收敛于解的误差估计,所得结果是某些已知结果的改进和推广。     

Large time and small noise asymptotic results for mean reverting diffusion processes with applications

Summary. We use the theory of large deviations to investigate the large time behavior and the small noise asymptotics of random economic processes whose evolutions are governed by mean-reverting stochastic differential equations with (i) constant and (ii) state dependent noise terms. We explicitly show that the probability is exponentially small that the time averages of these process will occupy regions distinct from their stable equilibrium position. We also demonstrate that as the noise parameter decreases, there is an exponential convergence to the stable position. Applications of large deviation techniques and public policy implications of our results for regulators are explored. Received: December 7, 1998; revised version: October 25, 1999     

Approximating Large Diversified Portfolios

This paper considers a financial market with asset price dynamics modeled by a system of lognormal stochastic differential equations. A one‐dimensional stochastic differential equation for the approximate evolution of a large diversified portfolio formed by these assets is derived. This identifies the asymptotic dynamics of the portfolio as being a lognormal diffusion. Consequentially an efficient way for computing probabilities, derivative prices, and other quantities for the portfolio are obtained. Additionally, the asymptotic strong and weak orders of convergence with respect to the number of assets in the portfolio are determined.     

Classical and Impulse Stochastic Control of the Exchange Rate Using Interest Rates and Reserves

We consider the problem of a Central Bank that wants the exchange rate to be as close as possible to a given target, and in order to do that uses both the interest rate level and interventions in the foreign exchange market. We model this as a mixed classical‐impulse stochastic control problem, and provide for the first time a solution to that kind of problem. We give examples of solutions that allow us to perform an interesting economic analysis of the optimal strategy of the Central Bank.     

关于常微分方程教学探索

常微分方程是高等教育的核心基础课程的一部分重要内容,是进一步学习泛函分析,偏微分方程,稳定性理论和控制论等方向的入门学科,具有很强的理论性与应用性的背景,因此,对该部分的教学的教师有责任进行教学设计与探索,以期取得令人满意的教学效果。     

一种基于神经网络提取旋波材料参数的新方法

提出了一种从测试的S参数中提取旋波材料参数的新方法——神经网络法。针对旋波材料参数的自由空间测试方法，本文采用BP神经网络来构建映射模型，利用不同算法对网络进行训练，从而获得所需的网络。结果表明，该方法计算速度快、精度高，解决了求解非线性方程组解的模糊性问题，确保了测试结果的可靠性。该方法所构建的网络可用于材料测试后旋波材料参数的快速提取。     

OPTIMAL INVESTMENT UNDER RELATIVE PERFORMANCE CONCERNS

We consider the problem of optimal investment when agents take into account their relative performance by comparison to their peers. Given N interacting agents, we consider the following optimization problem for agent i, : where is the utility function of agent i, his portfolio, his wealth, the average wealth of his peers, and is the parameter of relative interest for agent i. Together with some mild technical conditions, we assume that the portfolio of each agent i is restricted in some subset . We show existence and uniqueness of a Nash equilibrium in the following situations:

• ‐ unconstrained agents,
• ‐ constrained agents with exponential utilities and Black–Scholes financial market.

We also investigate the limit when the number of agents N goes to infinity. Finally, when the constraints sets are vector spaces, we study the impact of the s on the risk of the market.     

我国公共支出增长及波动对经济增长的影响研究

文章采用随机增长模型来研究政府的公共开支的增长与波动对经济增长的影响。首先,文章给出了随机优化问题的理论基础;然后给出了一个随机增长模型,该模型把公共开支与经济增长联系起来,从理论上推导分析公共开支的平均增长和波动对经济增长的影响;接着选取我国31个省份1995-2012年间在科教文化、社会福利、环境保护、交通运输方面的公共支出的平均值和方差为解释变量建立了多元线性回归模型,实证检验表明:这四种类型公共支出的增长和波动可能促进经济增长也可能阻碍经济增长;文章最后给出了相应的分析和建议。     

Econometric forecasts of tourism demand to 2005

A complete system of demand equations which was developed previously to generate forecasts of tourism imports and exports is modified to allow for destination-specific demand structures in the tourism export functions. The new model is shown to be considerably more realistic than the original one, and represents a major conceptual improvement. Furthermore, the modified complete system of demand equations yields more accurate outof-sample forecasts, across both varying time horizons and types of forecast. The new model is used to generate forecasts of tourism imports and exports for 18 countries and various major geographical areas, including the recently expanded European Union, for the period up to 2005 for different scenarios.