A Model of Choice for Public Policy

Punctuated equilibrium is supposed to be a viable alternativeto incrementalism, and, indeed, the authors of the model havesometimes made such claims. But punctuated equilibrium was developedto explain change in policy subsystems and does not serve asa complete model of policy choice in the same way that incrementalismhas served. This article develops a full-blown and viable modelof choice for public policy based on disproportionate informationprocessing. Its dynamics are based in the allocation of politicalattention to policy topics and the manner in which politicalsystems process information. The model leads directly to outcomesthat are consistent with punctuated equilibrium and are notgenerally consistent with incrementalism. Incrementalism, however,may be deduced from the model as a special case. The model isbest tested using stochastic process approaches. Incrementalismlogically must yield a normal distribution of outcomes, butdisproportionate information processing yields leptokurtic outcomes.Adding institutional constraints only makes the stochastic processimplications more severe. To support our arguments, we presentboth static and dynamic simulations of these processes. We alsoshow that these simulations are consistent with observationsof U.S. government budgets.