Option Pricing Model with Fuzzy Measures under Knightian Uncertainty

Conventionally, the risk is described with a unique probability measure. However, Ellsberg paradox indicates that the existence of Knightian uncertainty would have an effect on both decision-makers' behavior and asset pricing. In this article, an option-pricing model is proposed under Knightian uncertainty using the λ-fuzzy measure and the Choquet integral, and the equilibrium price of European option on a non-dividend-paying stock is deduced. The equilibrium price is found to be an interval instead of a determinate number, which is in accordance with the conclusion of Epstein conclusion. Subsequent experimental research and the outcome indicate that the parameter λ which can describe human subjective sentimental will change with volatility of personal mood. Moreover, this study will pave a novel way to cope with other derivatives pricing under Knightian uncertainty.