Given the price of a call or put option, the Black-Scholes implied volatility is the unique volatility parameter for which the Bulack-Scholes formula recovers the option price. This article surveys research activity relating to three theoretical questions: First, does implied volatility admit a probabilistic interpretation? Second, how does implied volatility behave as a function of strike and ...

In the paper we study the relationship between macroeconomic and stock market volatility, using S&P500 data for the period 1970-2001. We find weak evidence of long memory in volatility once structural change is accounted for and a twofold linkage between stock market and macroeconomic volatility: macroeconomic volatility explains the persitent dynamics in stock market volatility, while stock ma...

Study of volatility has been considered by the academics and decision makers dur-ing two last decades. First since the volatility has been a risk criterion it has been used by many decision makers and activists in capital market. Over the years it has been of more importance because of the effect of volatility on economy and capital markets stability for stocks, bonds, and foreign exchange mark...

In recent years, authors have focused on modeling and forecasting volatility in financial series it is crucial for the characterization of markets, portfolio optimization and asset valuation. One of the most used methods to forecast market volatility is the linear regression. Nonetheless, the errors in prediction using this approach are often quite high. Hence, continued research is conducted t...

We describe a method for generating sentences from “keywords” or “headwords”. This method consists of two main parts, candidate-text construction and evaluation. The construction part generates text sentences in the form of dependency trees by using complementary information to replace information that is missing because of a “knowledge gap” and other missing function words to generate natural ...