Dudley, William

I will try to define some of the important characteristics of asset price bubbles. I will argue that bubbles do exist and that bubbles typically occur after an innovation that has created uncertainty about fundamental valuations. This has two important implications. First, a bubble is difficult to discern and, second, each bubble has unique characteristics. This implies that a rules-based approach to bubbles is likely to be ineffective and that tackling bubbles to diminish their potential to destabilize the financial system requires judgment.