Jorge Ludlow Universidad Autónoma Metropolitana   Av. San pablo 180 México City, DF 02200 México   jlw@nechikali.azc.uam.mx     Biographical Sketch: Ph in Mathematics, working in Time Series, applied work in Finance and Macroeconomics.   Primary Research Focus: Nonlinear Time Series   JEL Areas: C2 : Single Equation Models; Single Variables: General C3 : Multiple or Simultaneous Equation Models: General