Jouini, E. (1997).
Wolfgang Runggaldier (Ed.), Financial Mathematics
The theory of asset pricing, which takes its roots in the Arrow-Debreu model, the Black and Scholes formula, has been famalized in a framework by Harrison and Kreps (1979), harrison and Pliska (1979) and Kreps (1981). In these models, securities markets are assumed to be frictionless. The main result is that a price process is arbitrage free (or, equivalently, compatible with some equilibrium) if and only if it is, when appropriately renormalized, a martingale for some equivalent probability measure. The theory of pricing by arbitrage floows from there. Contingent claims can be priced by taking their expected value with respect to an equivalent marti…