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61.
本文在考虑产出波动的前提下,将个人的社会地位纳入消费者的效用函数,建立连续时间内的随机内生经济增长模型,利用随机最优化方法,分析随机波动和个人资本存量的变化对经济增长的影响.  相似文献   
62.
Pairwise linear discriminant analysis can be regarded as a process to generate rankings of the populations. But in general, not all rankings are generated. We give a characterization of generated rankings. We also derive some basic properties of this model.  相似文献   
63.
We analyze the phenomenon of stochastic resonance in an Ising-like system on a small-world network. The system, which is subject to the combined action of noise and an external modulation, can be interpreted as a stylized model of opinion formation by imitation under the effects of a “fashion wave”. Both the amplitude threshold for the detection of the external modulation and the width of the stochastic-resonance peak show considerable variation as the randomness of the underlying small-world network is changed. Received 19 December 2001  相似文献   
64.
We find that area and population distributions of nations follow an inverse power-law, as is known for cities, but with a different exponent. To interpret this result, we develop a growth model based on the geometrical properties of partitioning of the plane. The substantial agreement between the model and the actual nation distributions motivates the hypothesis that the distribution of aggregates of organisms is related to land partitioning. To test this hypothesis we follow the development of bacterial colonies of Escherichia coli, which, compared to humans, are on a completely different level of complexity. We find that the distributions of E. coli colonies follow an inverse power law with exponent similar to that of nations.  相似文献   
65.
A folk theorem which holds for all repeated matching games is established. The folk theorem holds any time the stage game payoffs of any two players are not affinely equivalent. The result is independent of population size and matching rule—including rules that depend on players choices or the history of play.   相似文献   
66.
67.
Mingfeng He  Chuan Li  Tianliang Ma 《Physica A》2008,387(7):1621-1627
Nowadays in the rural areas of China, peasants can make their own choices to go to the city for a new job or stay in the rural area. A decision is made based on working ability and the information a peasant gets. A multivariate evolutionary model of this problem is established and the numerical simulation shows that going to the city brings about a rise in the peasants’ income, and also that such a rise, as well as the number of peasants going to the city, is influenced by the capacity of the cities and income gap between agricultural and non-agricultural industries.  相似文献   
68.
We present a model of social systems as special types of games in extensive form in which perception and learned strategies play an important role. We discuss personality, emotions, and the relation of utility to Maslow's hierarchy of values. We also formulate a new class of games, partially cooperative games, and attempt to define a solution concept for these.  相似文献   
69.
Classical approachs for fitting and aggregation problems, specially in cluster analysis, social choice theory and paired comparisons methods, consist in the minimization of a remoteness function between relational data and a relational model. The notion of median, with its algebraic, metric, geometrical and statistical aspects, allow a unified treatment of many of base problems. Properties of median procedures are organized according to four directions: stabilities and axiomatic characterizations; Arrow-like properties; combinatorial properties; effective computational possibilities. Finally, interesting mathematical problems, related to the notion of median are surveyed.  相似文献   
70.
The multiple judge,multiple criteria ranking problem: A fuzzy set approach   总被引:1,自引:0,他引:1  
This paper investigates the problem of selecting, from a set of issues, those which best satisfy a collection of criteria. A group of judges have fuzzy sets defined over the issues, for each criterion, whose values lie in a finite linearly ordered set L. These judges also have fuzzy sets defined over the set of criteria. The paper discusses methods of aggregating all the fuzzy sets into one fuzzy set μ, defined on the issues, so that μA?L gives the final ranking for issue A.  相似文献   
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