The martingale theory of price bubbles defines an asset bubble to exist when the asset's price process is a strict local martingale, that is, a local martingale that is not a martingale. Using this definition of a price bubble, for continuous semimartingales, we characterize the conditions under...

We develop a tractable partial equilibrium model to analyze the impact on the bond market generated by a ban on naked credit default swaps. We demonstrate that such a ban will have a negligible impact on the borrowing costs if CDS speculators are risk averse and take positions which are small...