This paper outlines the beginnings of a general theory of critical events. Four types are defined. Two are micro-events each affecting a small number of people and are shown to arise in everyday life. Two are macro-events that affect large numbers of people and are related to ‘shocks’ in...

We study the small-world network model, which mimics the transition between regular-lattice and random-lattice behavior in social networks of increasing size. We contend that the model displays a normal continuous phase transition with a divergent correlation length as the degree of randomness...

The critical boundaries separating ordered from chaotic behavior in randomly wired S-state networks are calculated. These networks are a natural generalization of random Boolean net and are proposed as an extended approach to genetic regulatory systems, sets of cells in different states or...

A model of biological morphogenesis is presented. The model is based in a gene-network cell description plus the interaction among cells. Here interactions between nearest cells are due to diffusion-like mechanisms and also to inductive, cell-to-cell interactions. The gene network properties are...

We calculate equilibria of dynamic double-auction markets in which agents are distinguished by their preferences and information. Over time, agents are privately informed by bids and offers. Investors are segmented into groups that differ with respect to characteristics determining information...