No abstract

The empirical application of Stochastic Volatility (SV) models has been limited due to the difficulties involved in the evaluation of the likelihood function. However, recently there has been fundamental progress in this area due to the proposal of several new estimation methods that try to overcome this problem, being at the same time, empirically feasible. As a consequence, several extensions of the SV models have been proposed and their empirical implementation is increasing. In this paper, we review the main estimators of the parameters and the volatility of univariate SV models proposed in the literature. We describe the main advantages and limitations of each of the methods both from the theoretical and empirical point of view. We complete the survey with an application of the most important procedures to the S&P 500 stock price index.

a b s t r a c tEmerging economies with inflation targets (IT) face a dilemma between fulfilling the theoretical conditions of "strict IT", which imply a fully flexible exchange rate, or applying a "flexible IT", which entails a de facto managed-floating exchange rate with foreign exchange (forex) interventions to moderate exchange rate volatility. Using a panel data model for 37 countries we find that, although IT lead to higher exchange rate instability than alternative regimes, forex interventions in some IT countries have been more effective to lower volatility than in non-IT countries, which may justify the use of "flexible IT" by policymakers.

thank seminar participants at the Banco de España, the European Central Bank, the XIX Finance Forum in Granada, the II t Workshop in Time Series Econometrics in Zaragoza, the VIII Workshop in Public Policy Design in Girona and the II Workshop on International Financial Markets in Ottawa. The opinions expressed in this document are solely the responsibility of the authors and do not represent the views of the Banco de España.

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