Integrated assessment models have become the primary tools for comparing climate policies that seek to reduce greenhouse gas emissions. Policy comparisons have often been performed by considering a planner who seeks to make optimal trade-offs between the costs of carbon abatement and the...

The climate policy debate has been dominated by economic estimates of the costs of policies to reduce greenhouse gas emissions. Yet the models used to derive those estimates are based on assumptions that have largely gone untested. The conventional approach embodies structural features that rule...