In a model with multiple Pareto-ranked equilibria we add trade in assets that pay based on the realization of a sunspot. Asset trading restricts the equilibrium set in a way that raises welfare by eliminating equilibria with a high likelihood of disasters. When the probability of a disaster is...

Aside from the equilibrium that Hotelling (1931) displayed, his model of non-renewable resources also contains a continuum of bubble equilibria. In all the equilibria the price of the resource rises at the rate of interest. In a bubble equilibrium, however, the consumption of the resource peters...

Stock-market crashes tend to follow run-ups in prices. These episodes look like bubbles that gradually inflate and then suddenly burst. We show that such bubbles can form in a Zeira-Rob type of model in which demand size is uncertain. Two conditions are sufficient for this to happen: A declining...

When a takeover is announced, the sum of the stock-market values of the firms involved often falls, and the value of the acquirer almost always does. Does this mean that takeovers do not raise the values of the firms involved? Not necessarily. We set up a model in which the equilibrium number of...

A new technology or product is often developed by the single entrepreneur. Whether he reaches the public offering stage or is acquired by a listed firm it takes time for the innovator to add value to the stock market. Indeed first, reduce the market's value because some firms -- usually large or...