Many social networks, apart from displaying scale-free characteristics observed in some instances, possess another remarkable feature that distinguishes them from those that appear in biological and technological context—assortativity. However, little or no attention has been payed to the...

The attractive possibility that financial indices may be chaotic has been the subject of much study. In this paper we address two specific questions: "Masked by stochasticity, do financial data exhibit deterministic nonlinearity?", and "If so, so what?". We examine daily returns from three...

We introduce a new dynamic immunization method based on the static immunization algorithm and study the relationship between dynamic and static immunization. By nodes to be immunized according to static immunization strategies, we build a connection between dynamic and static immunization. Using...

During the alternating day–night cycle, people have differing behavior and hence different connection patterns—such as going to work or home, shopping and so on. Hence, the true topological structure of human contact networks are not only time-varying but also exhibit certain distribution...

Price changes in financial data fluctuate irregularly or stochastically. This paper investigates whether the irregular fluctuations are random or have some kind of dynamics by applying a recently developed method, the small-shuffle surrogate method. The data used are daily gold price, daily...

We propose a method from the viewpoint of deterministic dynamical systems to investigate whether observed data follow a random walk (RW) and apply the method to several financial data. Our method is based on the previously proposed small-shuffle surrogate method. Hence, our method does not...

Moral behaviour, and more recently wisdom and prudence, are emerging as areas of interest in the study of business ethics and management. The purpose of this article is to illustrate that Cicero—lawyer, politician, orator and prolific writer, and one of the earliest experts in the field...

A voluntary vaccination allows for a healthy individual to choose vaccination according to the individual’s local information. Hence, vaccination has the potential to provide a complex negative feedback (non-infection decreases propensity for vaccination, hence increasing infection and vice...

We propose a new four state model for disease transmission and illustrate the model with data from the 2003 SARS epidemic in Hong Kong. The critical feature of this model is that the community is modelled as a small-world network of interconnected nodes. Each node is linked to a fixed number of...

Small world network models have been effective in capturing the variable behaviour of reported case data of the SARS coronavirus outbreak in Hong Kong during 2003. Simulations of these models have previously been realized using informed “guesses” of the proposed model parameters and tested...