1. A computer implemented method of calculating an estimated stock option price given a current stock price, historical prices of the stock, a strike price, a time duration, an estimated volatility, an estimated continuously compounded expected long-term rate of return of the stock, and a current continuously compounded risk-free rate of return, the method comprising the steps of: computing with a computer a conditional probability volatility parameter using said current continuously compounded expected long-term rate of return, said current continuously compounded risk-free rate of return, and said estimated volatility; determining a put-call parity adjustment factor to reflect at least one of a current market preference for put options and a current market preference for call options; and calculating a forecasted estimated stock option price using said conditional probability volatility parameter and said put-call parity adjustment factor.