As a function of strike and time to maturity the implied volatility estimation is a challenging task in financial … econometrics. Dynamic Semiparametric Factor Models (DSFM) are a model class that allows for the estimation of the implied … volatility surface (IVS) in a dynamic context, employing semiparametric factor functions and time-varying loadings. Because …

different lexica sentiment variables. These are employed for an analysis of stock reactions: volatility, volume and returns. An … increased (negative) sentiment will influence volatility as well as volume. This influence is contingent on the lexical … produce stock reaction indicators, including volatility, detrended log trading volume and return? (ii) To which degree is …

is the volatility coefficient which in turn obeys an autoregression type equation log v t = w + a S t- l + nt with an … problem of online estimation of current values of w = w(T) and a = a(T) from the observations SI , ... ,ST. We propose an … adaptive method of estimation which does not use any information about time homogeneity of the obscured process. We apply this …