Cities and Complexity ─ Understanding Cities With Cellular Automata, Agent-Based Models, and Fractals

As urban planning moves from a centralized, top-down approach to a decentralized,bottom-up perspective, our conception of urban systems is changing. In Cities andComplexity, Michael Batty offers a comprehensive view of urban dynamics in the context ofcomplexity theory, presenting models that demonstrate how complexity theory can embrace a myriad ofprocesses and elements that combine into organic wholes. He argues that bottom-up processes -- inwhich the outcomes are always uncertain -- can combine with new forms of geometry associated withfractal patterns and chaotic dynamics to provide theories that are applicable to highly complexsystems such as cities.

Batty begins with models based on cellular automata (CA),simulating urban dynamics through the local actions of automata. He then introduces agent-basedmodels (ABM), in which agents are mobile and move between locations. These models relate to manyscales, from the scale of the street to patterns and structure at the scale of the urban region.Finally, Batty develops applications of all these models to specific urban situations, discussingconcepts of criticality, threshold, surprise, novelty, and phase transition in the context ofspatial developments. Every theory and model presented in the book is developed through examplesthat range from the simplified and hypothetical to the actual. Deploying extensive visual,mathematical, and textual material, Cities and Complexity will be read both byurban researchers and by complexity theorists with an interest in new kinds of computationalmodels.

Sample chapters and examples from the book, and other related material,can be found at http://www.complexcity.info

Michael Batty is Bartlett Professor of Planning and Director of the Centre for Advanced Spatial Analysis (CASA) at University College London.