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31.
在一个带有生产扰动和公共支出扰动的随机模型中,把教育的产出--人力资本引入效用函数和生产函数,利用随机最优化方法,确定了最优经济增长率和最优个体教育投资率.通过分析参数,得出了最优税率. 相似文献
32.
Conditional interactions are common in both human and animal societies. To understand the impacts of this feature on the evolution of cooperation, we propose a modified public goods game combined with conditional interactions in terms of the aspiration payoffs. Through simulations, we find that the function of the fraction of cooperators and the synergy factor is non-monotonic. This indicates that a large synergy factor is not always in favor of the promotion of cooperation. In addition, for a high aspiration, the typical coexistence state of cooperators and defectors could disappear, and the system demonstrates a sharp transition from the complete defection state to the complete cooperation state as the synergy factor increases. Furthermore, an interesting critical phenomenon is found in a finite system, i.e., the system can randomly evolve into a complete defection state or a complete cooperation state. An explanation of these evolutionary outcomes is provided in this paper, which is in agreement with the simulation results. 相似文献
33.
提高专业基础课程学习的兴趣 总被引:1,自引:0,他引:1
课程教学质量直接影响学生学习的积极性,专业基础课程质量直接影响专门人才的培养。从"激光原理及应用"专业基础课程的教学过程如何激发学生的学习兴趣出发提出了一些想法,以打造顺应时代发展的光电子技术人才。 相似文献
34.
The existence of reputation can significantly promote the level of cooperation within the human population. In the recent years, most of the researches were based on binary image score or first-order evaluation standard. In this paper, we propose a second-order reputation evaluation model, in which the individual's image score will change not only in accordance with his own strategy, but also the reputation value of neighbors. Individuals try to enhance their reputation to cooperate with the surrounding high-reputation individuals, and then becomes an influential individual in the population. The existence of this mechanism renders the individuals who at the edge of the clusters formed by the cooperators to rapidly accumulate their reputation values through the adoption of cooperative strategy, and then the cooperative strategy can be spread widely and rapidly in the whole population. Through extensive numerical simulations, it is clearly indicated that the population cooperation behavior will be obviously improved when the individual's influence factor becomes smaller or the reputation step length increases. The current results are further conducive to understanding the emergence of cooperation in many real world systems. 相似文献
35.
介绍了作者利用新生研讨课的教学实践建设高分子中文科普网站的经验体会。作者在南京大学本科"三三制"教学改革的新形势下设立了新生研讨课,针对新生通识类课程的特点,引导学生在"大分子-从材料到生命"这一主题下,分小组协作建设某个具体相关专题的科普网站,从中体会合作互助式学习和探究式学习理念,以便使其更好地适应现代大学的学习生活。课程学员制作的"大分子花园"中文科普网站已初具规模,期待着学界同仁的共同参与! 相似文献
36.
具有可选服务的M/M/l排队模型的豫解集 总被引:1,自引:0,他引:1
邢喜民 《新疆大学学报(理工版)》2008,25(4)
运用线性算子及其共轭算子的谱之间的关系,研究具有可选服务的M/M/1排队模型主算子的豫解集,并得到在虚轴上除了零外其它所有点都属于该算子的豫解集. 相似文献
37.
Takuya Masuzawa 《International Journal of Game Theory》2008,37(2):185-201
In this paper, we discuss the computational complexity of the strategic cores of a class of n-person games defined by Masuzawa (Int J Game Theory 32:479–483, 2003), which includes economic situations with monotone externality.
We propose an algorithm for finding an α-core strategy of any game in this class which, counting the evaluation of a payoff
for a strategy profile as one step, terminates after O(n
3· M) operations, where M is the maximum size of a strategy set of any of the n players. The idea underlying this method is based on the property of reduced games.
This paper is based on a part of the doctoral dissertation of the author. The author thanks Mikio Nakayama, Masashi Umezawa,
William Thomson, an associate editor, and the anonymous referee for their helpful comments, suggestions, and advice. Thanks
are also due to Yukihiko Funaki for a comment that led the author to this subject. The author is responsible for errors and
inadvertencies. 相似文献
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This paper seeks to determine whether governments should intervene in the private annuity market by directly providing public insurance in the form of annuities when both the government and the insurance companies could default. It is found that, although the government could default, intervening by means of an annuity can improve social welfare if the insurance companies could default and the expected return on the public annuity is greater than the rate of return on a risk-free bond. We also find that, under actuarially fair pricing, the government should provide more in terms of a public annuity than the optimal amount of the annuity that the individual purchases in the private market if the government is less likely to default on the public annuity than an insurance company would in the case of a private annuity. 相似文献