Policy towards speculative bubbles is examined in a model of a finite horizon 'greater fool' bubble, with rational agents, asymmetric information and short-sales constraints. This model permits the use of standard tools of comparative dynamics and welfare economics to analyze bubble policies....

In this note I show that there is a mistake in the proof of uniqueness in Engelbrecht-Wiggans, Milgrom and Weber’s seminal “Competitive Bidding and Proprietary Information” and provide a correct proof.

We analyze an economy with asymmetric information and endogenize the possibilities for information transmission between members of a coalition. We then define a concept of the Core that takes into account these communication possibilities. The internal consistency of the improvements is...