Diversity and Complexity: (Primers in Complex Systems)

This book provides an introduction to the role of diversity in complex adaptive systems. A complex system--such as an economy or a tropical ecosystem--consists of interacting adaptive entities that produce dynamic patterns and structures. Diversity plays a different role in a complex system than it does in an equilibrium system, where it often merely produces variation around the mean for performance measures. In complex adaptive systems, diversity makes fundamental contributions to system performance. Scott Page gives a concise primer on how diversity happens, how it is maintained, and how it affects complex systems. He explains how diversity underpins system level robustness, allowing for multiple responses to external shocks and internal adaptations; how it provides the seeds for large events by creating outliers that fuel tipping points; and how it drives novelty and innovation. Page looks at the different kinds of diversity--variations within and across types, and distinct community compositions and interaction structures--and covers the evolution of diversity within complex systems and the factors that determine the amount of maintained diversity within a system. * Provides a concise and accessible introduction * Shows how diversity underpins robustness and fuels tipping points * Covers all types of diversity * The essential primer on diversity in complex adaptive systems

Table of Contents:
Acknowledgments ix Prelude: The Meaning of Diversity 1 Chapter 1: On Diversity and Complexity 16 Chapter 2: Measuring Diversity 54 Chapter 3: The Creation and Evolution of Diversity 79 Chapter 4: Constraints on Diversity 127 Chapter 5: Variation in Complex Systems 148 Chapter 6: Diversity's Inescapable Benefits I: Averaging 167 Chapter 7: Diversity's Inescapable Benefits II: Diminishing Returns to Types 183 Chapter 8: Diversity's Impact in Complex Systems 196 Chapter 9: Parting Thoughts 249 Bibliography 257 Notes 271 Index 281

About the Author :
Scott E. Page is the Leonid Hurwicz Collegiate Professor of Complex Systems, Political Science, and Economics at the University of Michigan and an external faculty member at the Santa Fe Institute. He is the author of The Difference: How the Power of Diversity Creates Better Groups, Firms, Schools, and Societies (Princeton).

Review :
"Scott Page effectively illustrates the multiplicity of results from diverse aspects of complex systems. While all too many social scientists have tried to focus on making analysis simple, Page points out that this overlooks the great variety of relevant material in our social worlds. I am looking forward to having my students read it in my graduate seminar and encourage others to do so as well."—Elinor Ostrom, winner of the Nobel Prize in economics "At once clear and precise, Page not only makes a persuasive case for the advantages of diversity in biological, ecological, and social systems alike, but also provides the reader with the analytical tools necessary to engage real-world debates in a rational, even quantitative manner. The result is a valuable primer on a difficult and important subject."—Duncan J. Watts, author of Small Worlds: The Dynamics of Networks between Order and Randomness "Scott Page has performed a remarkable work of synthesis. The concepts of diversity and its implications for performance and growth are common to many fields, especially biology and economics. Page has drawn these illustrations together and shown the common elements and how each field illuminates others."—Kenneth J. Arrow, winner of the Nobel Prize in economics "Page engagingly seduces readers into rather deep ideas in complex systems, including sophisticated mathematical formulas, by using a relaxed style with lots of examples. Yet the treatment is rigorous."—Simon A. Levin, Princeton University "One of the book's many strengths is that it draws upon insights from seemingly disconnected areas of research and shows how they can be viewed within a common framework. Page's style is lively and conversational, making challenging subject matter quite readable, but without any sacrifice of rigor. He manages to convey both the excitement and difficulty of analyzing complex systems and the role of diversity within them."—Rajiv Sethi, Barnard College, Columbia University