双目标旅行商问题及其蚂蚁算法实验研究

对双目标旅行商问题设计了基于Pareto概念的多目标蚂蚁算法.借助于算法的全局搜索能力,在整个解空间内快速搜索多目标组合的Pareto有效解,并利用多目标蚂蚁算法维持解集多样性的特点,使搜索到的Pareto解在前沿均匀分布.经大量算例求解验证了其有效性,该算法具有较好的通用性.     

传统观念的突破 现行实践的依据

“公平 效率”的关系始终伴随着中国经济改革,“均平原则”成为中国古代经济改革和稳定社会的指导思想,在中国社会的特定时期曾发挥了重要作用,但不可否认其是经济发展的严重桎梏,十六大围绕全面建设小康社会的目标,在观念、原则和措施上突破了传统“公平、效率”观的束缚,科学地把握了公平和效率的对立统一关系。     

浅论内部劳动力市场运行效率的几个问题

在市场经济条件下 ,劳动市场并非像新古典理论所描述的那样统一完整 ,而是处于分割的状态。如果以企业与市场的接触点为边界 ,那么我们可以把劳动市场划分为企业内部的劳动市场和企业外部的劳动市场两大块。内部劳动市场是一种不同于新古典模型的制度安排 ,它拥有独特的运行机制和效率基础。吸收西方经济学家在这方面的研究成果 ,探讨内部劳动市场的效率基础、限制条件及其对于国企就业体制改革具有启示意义     

论城市土地储备制度

本文利用新福利经济学的分析方法根据我国养老保险基金筹集模式的现状,指出其存在帕累托改进的可能,在比较和借鉴国际养老基金筹集模式的基础上,得出了强调养老保险基金筹集中个人责任的重要性,并对我国养老保险基金新模式的设计提出了自己的看法.     

一个求解多目标优化问题的排序算法

多目标演化算法的研究热点集中在Pareto最优概念的种群个体的比较与排序、适应值赋值与小生境技术等方面 .基于这一点 ,本文给出了一个排序算法 ,并验证了其有效性 .     

Harsanyi's Social Aggregation Theorem and Dictatorship

In this paper I investigate the possibility of a dictatorship in the context of Harsanyi's Social Aggregation Theorem. Preliminarily, some propositions about Harsanyi's Theorem are presented using an alternative principle that I name Quasi-strong Pareto, which is the latter part of Strong Pareto. Then I define dictatorship as a requirement that social preference agrees with a dictator's preference or those of members of dictatorial group even if their preferences strictly contradict those of all other people in the society. Conclusively, although in each version of Harsanyi's Theorem with Pareto Indifference, Weak Preference Pareto or Weak Pareto the social utility function may have a form of dictatorship, however if individuals' vNM utility functions are all 'individualistic' and Quasi-strong Pareto is satisfied, then the dictatorship is excluded.     

Inference and Optimal Design Based on Step—Partially Accelerated Life Tests for the Generalized Pareto Distribution under Progressive Type-I Censoring

Various types of failure, censored and accelerated life tests, are commonly employed for life testing in some manufacturing industries and products that are highly reliable. In this article, we consider the tampered failure rate model as one of such types that relate the distribution under use condition to the distribution under accelerated condition. It is assumed that the lifetimes of products under use condition have generalized Pareto distribution as a lifetime model. Some estimation methods such as graphical, moments, probability weighted moments, and maximum likelihood estimation methods for the parameters are discussed based on progressively type-I censored data. The determination of optimal stress change time is discussed under two different criteria of optimality. Finally, a Monte Carlo simulation study is carried out to examine the performance of the estimation methods and the optimality criteria.     

Test of two hypotheses explaining the size of populations in a system of cities

Two classical hypotheses are examined about the population growth in a system of cities: Hypothesis 1 pertains to Gibrat's and Zipf's theory which states that the city growth–decay process is size independent; Hypothesis 2 pertains to the so-called Yule process which states that the growth of populations in cities happens when (i) the distribution of the city population initial size obeys a log-normal function, (ii) the growth of the settlements follows a stochastic process. The basis for the test is some official data on Bulgarian cities at various times. This system was chosen because (i) Bulgaria is a country for which one does not expect biased theoretical conditions; (ii) the city populations were determined rather precisely. The present results show that: (i) the population size growth of the Bulgarian cities is size dependent, whence Hypothesis 1 is not confirmed for Bulgaria; (ii) the population size growth of Bulgarian cities can be described by a double Pareto log-normal distribution, whence Hypothesis 2 is valid for the Bulgarian city system. It is expected that this fine study brings some information and light on other usually considered to be more pertinent countries of city systems.     

基于改进的Pareto/NBD模型预测博客用户在线行为

博客用户在线行为分为发文行为和流失行为.由于这两种行为分别与交易过程中客户的购买行为和流失行为具有相似性,选择借鉴客户基分析中的Pareto/NBD模型进行预测.考虑到用户间交互性对博客用户在线行为具有重要影响,通过比例风险模型向经典的Pareto/NBD模型中加入体现用户间交互性的协变量.Pareto/NBD模型经过改进,实现了对博客用户在线行为的预测.实证研究以用户博客空间中的总评论量和总浏览量作为协变量.数据分析结果显示,当使用总评论量作为影响流失行为的协变量时,改进模型的预测精度显著提高.进一步分析还发现,总评论量对博客用户“存活”时长的正向激励存在着阈值.