Generalized Option Betas

Abstract

This paper extends the option betas presented by Cox and Rubinstein (1985) and Branger and Schlag (2007). In par- ticular, we show how the beta of the underlying asset affects both an option's covariance beta and its asset pricing beta. In contrast to Branger and Schlag (2007), the generalized option betas coincide if the options are evaluated according to the CAPM option pricing model of Husmann and Todorova (2011). The option betas are presented in terms of Black- Scholes option prices and are therefore easy to use in practice.