Market-Consistent Prices


Book Description

Arbitrage Theory provides the foundation for the pricing of financial derivatives and has become indispensable in both financial theory and financial practice. This textbook offers a rigorous and comprehensive introduction to the mathematics of arbitrage pricing in a discrete-time, finite-state economy in which a finite number of securities are traded. In a first step, various versions of the Fundamental Theorem of Asset Pricing, i.e., characterizations of when a market does not admit arbitrage opportunities, are proved. The book then focuses on incomplete markets where the main concern is to obtain a precise description of the set of “market-consistent” prices for nontraded financial contracts, i.e. the set of prices at which such contracts could be transacted between rational agents. Both European-type and American-type contracts are considered. A distinguishing feature of this book is its emphasis on market-consistent prices and a systematic description of pricing rules, also at intermediate dates. The benefits of this approach are most evident in the treatment of American options, which is novel in terms of both the presentation and the scope, while also presenting new results. The focus on discrete-time, finite-state models makes it possible to cover all relevant topics while requiring only a moderate mathematical background on the part of the reader. The book will appeal to mathematical finance and financial economics students seeking an elementary but rigorous introduction to the subject; mathematics and physics students looking for an opportunity to get acquainted with a modern applied topic; and mathematicians, physicists and quantitatively inclined economists working or planning to work in the financial industry.










Beyond Arbitrage


Book Description

One often wants to value a given asset or risky payoff by reference to observed prices of other assets rather than by exploiting full-fledged economic models. However, this approach breaks down if one cannot find a perfect replicating portfolio. We impose weak economic restrictions to derive usefully tight bounds on asset prices in this situation. The bounds basically rule out high Sharpe ratios - quot;good dealsquot; - as well as arbitrage opportunities. We show how to calculate the price bounds in two-period, multiperiod and continuous time contexts. We show that the multiperiod problem can be solved recursively as a sequence of two-period problems. We calculate bounds in option pricing examples including infrequent trading, an option written on a nontraded event, and in an environment with stochastic stock volatility and a varying riskfree rate.










Beyond Arbitrage


Book Description

It is often useful to price assets and other random payoffs by reference to other observed prices rather than construct full-fledged economic asset pricing models. This approach breaks down if one cannot find a perfect replicating portfolio. We impose weak economic restrictions to derive usefully tight bounds on asset prices in this situation. The bounds basically rule out high Sharpe ratios - `good deals' - as well as arbitrage opportunities. We present the method of calculation, we extend it to a multiperiod context by finding a recursive solution, and we apply it to option pricing examples including the Black-Scholes setup with infrequent trading, and a model with stochastic stock volatility and a varying riskfree rate.










Minimax Price Bounds in Incomplete Markets


Book Description

This paper develops an approach to tighten the bounds on asset pricing in an incomplete market that combines no-arbitrage pricing and preference-based pricing, and the approach is applied to call options without dynamic rebalancing. With the no-arbitrage pricing, it is straightforward to obtain the initial bounds, which are too wide to be of practical uses. By accepting that investors exhibit risk aversion from benchmark pricing kernels, it is possible to narrow the bounds considerably. Using the minimax deviation implicit in the parameters, one can restrict further the set of plausible values for call options on a stock.