To measure how policy changes affect social welfare, economists typically look at how policies affect behavior, and use a formal model to infer welfare consequences from the behavioral responses. But when different models can map the same behavior to very different welfare impacts, it becomes...

This paper focuses on the relationship between public action and access to public goods. It begins by developing a simple model of collective action which is intended to capture the various mechanisms that are discussed in the theoretical literature on collective action. We argue that several of...

To measure how policy changes affect social welfare, economists typically look at how policies affect behavior, and use a formal model to infer welfare consequences from the behavioral responses. But when different models can map the same behavior to very different welfare impacts, it becomes...