数据库维护的通用性技术探讨

本文从如何提高软件的开发效率及软件的可维护性出发,论述了如何对信息维护操作的通用性进行分析,采用面向对象设计方法,就一些常见信息维护操作中的外键维护、信息录入修改及通用信息操作提出解决方案和具体设计。     

Approximation of Optimal Reinsurance and Dividend Payout Policies

We consider the stochastic process of the liquid assets of an insurance company assuming that the management can control this process in two ways: first, the risk exposure can be reduced by affecting reinsurance, but this decreases the premium income; and second, a dividend has to be paid out to the shareholders. The aim is to maximize the expected discounted dividend payout until the time of bankruptcy. The classical approach is to model the liquid assets or risk reserve process of the company as a piecewise deterministic Markov process. However, within this setting the control problem is very hard. Recently several papers have modeled this problem as a controlled diffusion, presuming that the policy obtained is in some sense good for the piecewise deterministic problem as well. We will clarify this statement in our paper. More precisely, we will first show that the value function of the controlled diffusion provides an asymptotic upper bound for the value functions of the piecewise deterministic problems under diffusion scaling. Finally it will be shown that the upper bound is achieved in the limit under the optimal feedback control of the diffusion problem. This property is called asymptotic optimality .     

NONPARAMETRIC KERNEL-BASED SEQUENTIAL INVESTMENT STRATEGIES

The purpose of this paper is to introduce sequential investment strategies that guarantee an optimal rate of growth of the capital, under minimal assumptions on the behavior of the market. The new strategies are analyzed both theoretically and empirically. The theoretical results show that the asymptotic rate of growth matches the optimal one that one could achieve with a full knowledge of the statistical properties of the underlying process generating the market, under the only assumption that the market is stationary and ergodic. The empirical results show that the performance of the proposed investment strategies measured on past nyse and currency exchange data is solid, and sometimes even spectacular.     

制度与交往

考察制度与交往的关系可以有两个视角:从起源上说,交往是制度产生的现实基础.制度是社会关系的存在方式,社会关系是在交往中形成的,交往是社会关系的生成机制.因此,制度是交往的产物;从现实上说,制度又是交往的前提.制度既是社会交往的信任机制,同时又是社会交往秩序的建构机制.随着人类社会交往全球化的趋势,作为社会交往规则体系的制度也必将发生巨大的变革,从而形成世界性"普遍制度".     

Ethical Principles that Make the World and its Economy More Equal

Abstract

No doubt, the global economic (and political) structure is very unequal. The paper begins by demonstrating the various dimensions of this inequality as they relate to economic measures such as per capita GDP, degree of consumption and ownership, health measures, education, and power and influence in various global organizations such as the United Nations (UN), World Trade Organization (WTO), International Monetary Fund (IMF), and others. Next, the paper, supporting a more equal global economic and political structure, investigates the various instruments in welfare economies and ethics theory that can be utilized to justify a sort of distributional change that could lead to more global equality. Finding various economic and ethical instruments associated with utilitarianism, Pareto Optimality and the Hicks–Kaldor compensation test less than satisfactory in dealing with and advocating sufficient global distributional changes, we will investigate ethical principles developed by John Rawls in both his 1971 The Theory of Justice and his 1999 The Law of Peoples, Sen's capability approach, the debate between Rawls and Sen regarding their ethical principles, and whether or not those ethical principles can justify necessary global distributional changes. As we will argue, although the principles developed by Sen and Rawls can be utilized to justify global distributional changes to a degree, they cannot advocate a global difference principle that can justify sufficient global distributional changes. Attempt is made to develop a global difference principle that can justify and advocate more drastic distributional changes.     

“协和万邦”理念的传承和实践——兼论广西北部湾经济区发展定位问题

“和合、和为贵、协和万邦”是我国处理民族之间、国家之间关系的重要传统理念,是新中国“与邻为善、以邻为伴”周边外交方针与独立自主和平外交政策、推动建设和谐世界主张的重要思想渊源。弘扬“协和万邦”的理念对营造我国建设良好的国际环境,加快对外开放具有十分重要的意义。广西北部湾经济区“国际区域经济合作区”的发展目标定位,是“协和万邦”理念的具体实践与“和谐世界”主张的有益尝试。     

基于扩大内需的我国居民消费信贷博弈分析

消费信贷是新形势下刺激消费的一个重要举措,但由于信息不对称造成借款人的“逆向选择”与“道德风险”,导致我国的消费信贷推而不广。为提升我国消费信贷水平,扩大内需,银行应通过事前防范将消费者与银行之间的一次性博弈变为重复性博弈,通过事后补救加强对借款人的监督与对其违约行为的惩罚力度;同时要完善法律法规,构建高效的信息传递系统,重建个人信用体系,最终求得银行与消费者之间博弈的“帕累托最优”解。     

Information Structure and the Tragedy of the Commons in Resource Extraction

Synopsis This paper considers the well-known Levhari-Mirman discrete-time model of resource extraction, and investigates the effects of the information structure of the dynamic game – open-loop, Markovian or history-dependent – on the equilibrium consumption path and the overall utility of the agents. Due to the special structure of the model, the open-loop regime yields a Pareto-optimal outcome. The Markovian regime leads to the most pronounced version of the tragedy of the commons. History-dependent behavior yields an outcome set that is intermediate between the other two cases, and that may include the Pareto-optimal outcome in some cases. The level of efficiency of equilibrium behaviour is thus U-shaped as a function of the level of information the agents’ extraction strategies are based on. The analysis suggests that in environments characterized by a dynamic (and no market) externality, forcing agents to commit to open-loop behavior would constitute welfare-improving regulation.     

关于个人所得税制改革的探索

我国个人所得税从1980年实施以来，已运行了20多年，在调节个人收入公平、增加地方财政收入方面发挥着重要的作用。但是，随着经济的发展，现行的个人所得税制出现了许多弊端，产生了诸多问题，不利于经济的增长和社会的稳定。文章从个人所得税制模式的选择和改革的内容等方面，对个人所得税如何进行改革进行了分析。     

More optimal designs for diallel cross experiments

It is shown that the complement of a universally optimal design derivable from a triangular design is again universally optimal in a class of connected designs. Furthermore, some series of universally optimal designs for diallel cross experiments are provided. These observations strengthen the result on universally optimal designs by Das, Dey and Dean (1998). Received: August 1999