It is generally said that out-of-the-money call options are expensive and one can ask the question from which moneyness level this is the case. Expensive actually means that the price one pays for the option is more than the discounted average payoff one receives. If so, the option bears a...

Lower and upper prudent valuations in two price economies obtained on sufficiently distorting physical probabilities for returns to horizons matching option maturities straddle the market prices of options. Market prices are then modeled as geometric averages of the extremal valuations. Upper...

Nonlinear martingale theory is used to form lower and upper price processes straddling a martingale. The martingale return is then modeled in terms of risk charges associated with the returns on the straddling lower and upper processes. The move to physically expected returns is made via the...