Consider the options written on a tradable underlying asset S that follows the stochastic process:
dS = μSdt + ĻSdW,
where μ and Ļ are constant factors. Assume also that the risk-free interest rate is constant and flat.
(a) Derive the current pricing of a down-and-out European call option with current asset price Su, strike price K, barrier level below the strike price and current asset price, and under in-the-money (K conditions.
(b) Consider a look-back option with payoff at maturity taken to be:
max(Soverall - K, 0) = Ji,
where K is a predefined strike price and Soverall is the overall minimum price of the underlying asset during the life of the option. Suppose it has been issued at the current time. Derive the current pricing of this look-back option.