Carl Simon (School of Public Policy, University of Michigan)
02/11/2008, at noon in room 6050 ISR-Thompson.
Decision-makers and policy-analysts who fail to take a systems approach risk long-run disastrous consequences, as illustrated by environmental disasters like DDT, policy disasters like the Vietnam War, and business disasters like the current crunch in the US automobile industry. A systems approach requires the understanding that an object, organization, or policy under consideration is a component of a larger inter-connected network, that changes in the object under consideration can have repercussions in distant components of that network, and vice versa.
A systems approach usually entails constructing and analyzing a model of the overall system, with particular attention to the interactions of its components. In general, one starts with a simple model with strong simplifying assumptions about the components and their interactions, for example that the components and their links are all alike and are in equilibrium. A complex systems approach entails relaxing some of these stronger simplifying assumptions and asking which results still hold. Do the ways that individuals differ or connect to one another make a difference? Does it matter whether or not the world is in equilibrium or is changing dynamically? Systems approaches – both simple and complex --- in fields as diverse as demography, economics, ecology, biology, epidemiology, and traffic engineering share some remarkable commonalities, so that techniques and insights in one discipline can shed light on the operations of others.