This paper studies testing for a unit root for large n and T panels in which the cross-sectional units are correlated. To model this cross-sectional correlation, we assume that the data is generated by an unknown number of unobservable common factors. We propose unit root tests in this...

Cet article examine la nature, les cause et les effets de la globalisation, phenomene tres anciens et tres influence par le changement technologique.

This paper prepared for the Handbook of Statistics (Vol.14: "Statistical Methods in Finance"), surveys the subject of stochastic volatility. The following subjects are covered: volatility in financial markets (instantaneous volatility of asset returns, implied volatilities in option prices and...