The understanding of human behavior in sequential decision tasks is important for economics and socio-psychological sciences. In search tasks, for example when individuals search for the best price of a product, they are confronted in sequential steps with different situations and they have to...

The understanding of human behavior in sequential decision tasks is im- portant for economics and socio-psychological sciences. In search tasks, for example when individuals search for the best price of a product, they are confronted in sequential steps with di®erent situations and they have to...

The understanding of human behavior in sequential decision tasks is important for economics and socio-psychological sciences. In search tasks, for example when individuals search for the best price of a product, they are confronted in sequential steps with different situations and they have to...

The boards of large corporations sharing some of their directors are connected in complex networks. Boards are responsible for corporations' long-term strategy and are often involved in decisions about a common topic related to the belief in economical growth or recession. We are interested in...

We report results of studies carried out on a simple 2D shape space model of the immune system, where a network of clones is perturbed by long-lived molecules whose presence triggers the disappearance (avalanche) of existing clones. The resulting reorganizations of the system, which occur over...

We introduce a simple model of self-organizing hierarchies in animal societies which relies on a basic positive feedback mechanism reinforcing the ability of a given individual to win or lose in a hierarchical interaction, depending on how many times it won or lost in previous interactions. If a...

In this paper, co-evolution is used to examine the long-term evolution of business models in an industry. Two types of co-evolution are used: synchronous, whereby the entire population of business models is replaced with a new population at each generation, and asynchronous, whereby only one...

We introduce a simple mathematical model of regulation of division of labour in insect societies based on the notion of fixed response thresholds. Individuals with different thresholds respond differently to task-associated stimuli. Low-threshold individuals become involved at a lower level of...

The spatiotemporal behavior of the spread of influenza in France has been studied, and algebraic spatial correlations (with exponent ) spanning the whole territory have been found to be present as soon as the number of reported cases first starts to increase, about 15 to 25 weeks before the peak...

How infectious diseases spread in space within one cycle of an epidemic is an important question that has received considerable theoretical attention. There are, however, few empirical studies to support theoretical approaches, because data is scarce. Weekly reports obtained since 1984 from a...