The mathematics of networks

نویسنده

  • M. E. J. Newman
چکیده

In much of economic theory it is assumed that economic agents interact, directly or indirectly, with all others, or at least that they have the opportunity to do so in order to achieve a desired outcome for themselves. In reality, as common sense tells us, things are quite different. Traders in a market have preferred trading partners, perhaps because of an established history of trust, or simply for convenience. Buyers and sellers have preferred suppliers and customers. Consumers have preferred brands and outlets. And most individuals limit their interactions, economic or otherwise, to a select circle of partners or acquaintances. In many cases partners are chosen not on economic grounds but for social reasons: individuals tend overwhelmingly to deal with others who revolve in the same circles as they do, socially, intellectually or culturally. The patterns of connections between agents form a social network (Fig. 1) and it is intuitively clear that the structure of such networks must affect the pattern of economic transactions, not to mention essentially every other type of social interaction amongst human beings. Any theory of interaction that ignores these networks is necessarily incomplete, and may in fact be missing some important and crucial phenomena. In the last few decades, therefore, a researchers have conducted extensive investigations of networks in economics, mathematics, sociology and a number of other fields, in an effort to understand and explain network effects. The study of social (and other) networks has three primary components. First, empirical studies of networks probe network structure using a variety of techniques such as interviews, question-

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

FINITE-TIME PASSIVITY OF DISCRETE-TIME T-S FUZZY NEURAL NETWORKS WITH TIME-VARYING DELAYS

This paper focuses on the problem of finite-time boundedness and finite-time passivity of discrete-time T-S fuzzy neural networks with time-varying delays. A suitable Lyapunov--Krasovskii functional(LKF) is established to derive sufficient condition for finite-time passivity of discrete-time T-S fuzzy neural networks. The dynamical system is transformed into a T-S fuzzy model with uncertain par...

متن کامل

Synchronization criteria for T-S fuzzy singular complex dynamical networks with Markovian jumping parameters and mixed time-varying delays using pinning control

In this paper, we are discuss about the issue of synchronization for singular complex dynamical networks with Markovian jumping parameters and additive time-varying delays through pinning control by Takagi-Sugeno (T-S) fuzzy theory.The complex dynamical systems consist of m nodes and the systems switch from one mode to another, a Markovian chain with glorious transition probabili...

متن کامل

THE p-CENTER PROBLEM ON FUZZY NETWORKS AND REDUCTION OF COST

Here we consider the p-center problem on different types of fuzzy networks. In particular, we are interested in the networks with interval and triangular fuzzy arc lengths and vertex-weights. A methodology to obtain the best satisfaction level of the decision maker who wishes to reduce the cost within the tolerance limits is proposed. Illustrative examples are provided.

متن کامل

The Use of Data Envelopment Analysis in the Design of Internet Networks to Ensure the Quality of Service

Choosing a superior Internet network by users or providing a desirable Internet network by ISPs is always one of the important decision issues in this area. Choosing a unique optimal network from among the best networks is still a big challenge. The purpose of this paper is to use the data envelopment analysis (DEA) decision-making technique to evaluate the existing Internet networks in order t...

متن کامل

Hypercube Bivariate-Based Key Management for Wireless Sensor Networks

Wireless sensor networks are composed of very small devices, called sensor nodes,for numerous applications in the environment. In adversarial environments, the securitybecomes a crucial issue in wireless sensor networks (WSNs). There are various securityservices in WSNs such as key management, authentication, and pairwise keyestablishment. Due to some limitations on sensor nodes, the previous k...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2004