Hull-White Option Stochastic Volatility Model
Due to its simplicity, the Black-Scholes-Merton (BSM) model has been widely used by financial institutions and traders for option pricing. However, the BSM model has a number of important assumptions that do not exist in the real world, and one of them is constant volatility. On a real market, volatility is a random, stochastic substance. One of the earliest attempts to improve the BSM by implementing stochastic volatility was the work by John Hull and Alan White, published in 1987 — The Pricing of Options on Assets with Stochastic Volatilities. The Hull-White stochastic-volatility model is useful to know and simple to implement, so, let's analyze it.