Occasionally, analytic models have found their way into complex policy negotiations. This article scrutinizes four such cases. When they appear independent and credible, models can play a variety of traditional mediating roles: They can foster learning, help define the negotiating agenda,...

As in most cases of natural disasters, relief needs arising out of the Mount St. Helens volcanic eruptions in May 1980 were greatly overestimated. Technical, bureaucratic, and political considerations all contribute to the upward bias in such cases. The errors in early estimates of relief needs...