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81.
In this paper, we present a model of social interaction systems. By comparing it with existing analytical models, and using simulations, we focus on dynamical behavior and interaction properties of this nonlinear time-varying system. The system's behavior can be predicted if we have sufficient knowledge of system parameters such as the connection matrix. Observation of system behavior can be useful to recover the unknown or insufficiently known levels of interaction strength. Furthermore, if proper sampling can be carried out, the system can be identified. This model is suitable for investigating social phenomena such as the fashion phenomenon. 相似文献
82.
The tradeoff between the speed and quality of the solutions obtained by various construction and local search algorithms for the elementary bin packing problem (BPP) are analyzed to obtain useful information for designing algorithms for real-world problems that can be modeled as BPPs. On the basis of intensive computational experiments, we observe that the framework of a solution (i.e., a part of a solution consisting of large items or items with tight constraints) should be constructed in the early stages of a local search. New local search algorithms are proposed as empirical support for the observation. 相似文献
83.
This paper derives the owner’s optimal contract with a bonus-incentive and audit when the owner delegates the investment timing decision to a manager with private information on an investment project. The optimal solution not only unifies the previous studies, but also accounts for actual auditing systems in firms. 相似文献
84.
E. Ben-Naim F. Vazquez S. Redner 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,49(4):531-538
We model the dynamics of social structure by a simple interacting particle
system. The social standing of an individual agent is represented by an
integer-valued fitness that changes via two offsetting processes. When two
agents interact one advances: the fitter with probability p and the less
fit with probability 1-p. The fitness of an agent may also decline with
rate r. From a scaling analysis of the underlying master equations for
the fitness distribution of the population, we find four distinct social
structures as a function of the governing parameters p and r. These
include: (i) a static lower-class society where all agents have finite
fitness; (ii) an upwardly-mobile middle-class society; (iii) a hierarchical
society where a finite fraction of the population belongs to a middle class
and a complementary fraction to the lower class; (iv) an egalitarian
society where all agents are upwardly mobile and have nearly the same
fitness. We determine the basic features of the fitness distributions in
these four phases. 相似文献
85.
M. N. Kuperman M. Ballard F. Laguna 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(3):513-520
A model for a dynamic network consisting of changing
local interactions is presented in this work. While the network
maintains solely local connections, certain properties known only
to Small World Networks may be extracted due to the dynamic nature
of the model. At each time step the individuals are grouped into
clusters creating neighborhoods or domains of fully connected
agents. The boundaries of these domains change in time,
corresponding to a situation where the links between individuals
are dynamic only throughout the history of the network. A question
that we pose is whether our model, which maintains a local
structure such that diffusion calculations are possible, might
lead to analytic or conceptual advances for the much more
complicated case of diffusion on a static disordered network that
exhibits the same macroscopic properties as our dynamic
ordered network. To answer this, we compare certain properties
which characterize the dynamic domain network to those of a Small
World Network, and then analyze the diffusion coefficients for
three possible domain mutations. We close with a comparison and
confirmation of previous epidemiological work carried out on
networks. 相似文献
86.
Christian von Scheve Daniel Moldt Julia Fix Rolf von Luede 《Computational & Mathematical Organization Theory》2006,12(2-3):81-100
This contribution investigates the function of emotion in relation to norms, both in natural and artificial societies. We
illustrate that unintentional behavior can be normative and socially functional at the same time, thereby highlighting the
role of emotion. Conceiving of norms as mental objects we then examine the role of emotion in maintaining and enforcing such
propositional attitudes. The findings are subsequently related to social structural dynamics and questions concerning micro-macro
linkage, in natural societies as well as in artificial systems. Finally, we outline the possibilities of an application to
the socionic multi-agent architecture SONAR.
Christian von Scheve graduated in Sociology with minors in Psychology, Economics, and Political Science at the University of Hamburg, where he
also worked as a research assistant at the Institute of Sociology. Currently, he is a 3rd year PhD student at the University
of Hamburg. He was a Fellow of the Research Group “Emotions as Bio-Cultural Processes” at the Center for Interdisciplinary
Research (ZiF) at Bielefeld University. In his doctoral thesis he develops an interdisciplinary approach to emotion and social
structural dynamics, integrating emotion theories from the neurosciences, psychology, and the social sciences. He has published
on the role of emotion in large-scale social systems, human-computer interaction, and multi-agent systems. He is co-editor
of a forthcoming volume on emotion regulation.
Daniel Moldt received his BSc in Computer Science/Software Engineering from the University of Birmingham (England) in 1984, graduated
in Informatics at the University of Hamburg, with a minor in Economics in 1990. He received his PhD in Informatics from the
University of Hamburg in 1996, where he has been a researcher and lecturer at the Department of Informatics since 1990. Daniel
Moldt is also the head of the Laboratory for Agent-Oriented Systems (LAOS) of the theoretical foundations group at the Department
of Informatics. His research interests focus on theoretical foundations, software engineering and distributed systems with
an emphasis on agent technology, Petri nets, specification languages, intra- and inter-organizational application development,
Socionics and emotion in informatics.
Julia Fix is currently a PhD student at the Theoretical Foundations of Computer Science Group, Department for Informatics at the University
of Hamburg. She studied Informatics and Psychology at the University of Hamburg, with an emphasis on theoretical foundations
of multi-agent systems and wrote her diploma theses about emotional agent systems. Her current research interests focus on
conceptual challenges and theoretical foundations of modelling emotions in multi-agent systems, emotion-based norm enforcement
and maintenance, and Socionics. A further research focus are Petri nets, in particular the use of Petri-net modelling formalisms
for representing different aspects of emotion in agent systems.
Rolf von Lüde is a professor of Sociology at the University of Hamburg with a focus in teaching and research in Sociology of Organizations,
Work and Industry since 1996. He graduated in Economics, Sociology, and Psychology, and received his doctorate in Economics
and the venia legendi in Sociology from the University of Dortmund. His current research focuses on labor conditions, the
organization of production, social change and the educational system, the organizational structures of university, Socionics
as a new approach to distributed artificial intelligence in cooperation with computer scientists, new public management, and
emotions and social structures. Rolf von Lüde is currently Head of Department of Social Sciences and Vice Dean of the School
of Business, Economics and Social Sciences, University of Hamburg. 相似文献
87.
Eyal Beigman 《Discrete Mathematics》2007,307(16):2074-2081
Arrow's impossibility theorem [K.J. Arrow, Social Choice and Individual Values, Wiley, New York, NY, 1951] shows that the set of acyclic tournaments is not closed to non-dictatorial Boolean aggregation. In this paper we extend the notion of aggregation to general tournaments and we show that for tournaments with four vertices or more any proper symmetric (closed to vertex permutations) subset cannot be closed to non-dictatorial monotone aggregation and to non-neutral aggregation. We also demonstrate a proper subset of tournaments that is closed to parity aggregation for an arbitrarily large number of vertices. This proves a conjecture of Kalai [Social choice without rationality, Reviewed NAJ Economics 3(4)] for the non-neutral and the non-dictatorial and monotone cases and gives a counter example for the general case. 相似文献
88.
Ruth L. Greenstein 《Applied biochemistry and biotechnology》1985,11(6):489-506
In late 1984, the Reagan administration proposed a Coordinated Framework for Regulation of Biotechnology. Its proposed regulatory
approach appears less constraining than the deep concerns of the 1970s concerning the risk of biotechnology would have suggested.
Several distinctive characteristics of the early period of biotechnology, particularly the role of the research community
in developing the initial regulatory system and the extent of federal funding, explain this development. The administration’s
proposal may attract substantial support. However, implementation may lead to conflicts and problems, especially concerning
human germ-line gene therapy and environmental release of viable genetically engineered organisms. 相似文献
89.
周焯华 《数学的实践与认识》2004,34(12):100-106
可计算一般均衡 (CGE)模型的参数估计或校准要求一个一致性的数据 ,而这个一致性的数据集则由社会核算矩阵 SAM(Social Accounting Matrix)所构成 .由于在许多国家特别是发展中国家 ,由于构成SAM的各种数据来源不同可能使这些来源不同的数据不一致 ,因此如何平衡和估计 SAM则是一个困难和关键的问题 .本文用交互熵方法如何建立和平衡 SAM. 相似文献
90.
Multi-objective optimization has been successfully applied to problems of industrial design, problems of quality control and production management, and problems of finance. The theme of these applications is how to choose the best solution for the decision makers out of a set of non-inferior solutions to a multi-objective optimization problem. For this purpose, an optimization model with hierarchical structure, whose lower problem is a multi-objective optimization problem and the upper problem is a preference optimization problem on a set of non-inferior solutions, must be constructed. This kind of hierarchical problems have been previously analyzed only with regard to linear programming problems by Benson[6]. In this paper, an algorithm is derived that provides a solution as a social choice, obtained by aggregating plural decision-makers' preferences. In the case of the simple majority rule, the bi-objective problem is transformed into an -parameter choice problem, and the golden section method is applied. The availability of the approach is demonstrated with the means of an illustrative example.Technische Universität BerlinFaculty of Science and Technology, Keio University 相似文献