Signals and Boundaries - 9780262017831

Complex adaptive systems (cas), including ecosystems, governments, biological cells,and markets, are characterized by intricate hierarchical arrangements of boundaries and signals. Inecosystems, for example, niches act as semi-permeable boundaries, and smells and visual patternsserve as signals; governments have departmental hierarchies with memoranda acting as signals; and soit is with other cas. Despite a wealth of data and descriptions concerning different cas, thereremain many unanswered questions about "steering" these systems. In Signals andBoundaries, John Holland argues that understanding the origin of the intricatesignal/border hierarchies of these systems is the key to answering such questions. He develops anoverarching framework for comparing and steering cas through the mechanisms that generate theirsignal/boundary hierarchies.

Holland lays out a path for developing the frameworkthat emphasizes agents, niches, theory, and mathematical models. He discusses, among other topics,theory construction; signal-processing agents; networks as representations of signal/boundaryinteraction; adaptation; recombination and reproduction; the use of tagged urn models (adapted fromelementary probability theory) to represent boundary hierarchies; finitely generated systems as away to tie the models examined into a single framework; the framework itself, illustrated by asimple finitely generated version of the development of a multi-celled organism; and Markovprocesses.