Alfonso Novales is a Professor of Economics at the Department of Quantitative Economics at Universidad Complutense (Madrid). He holds a Ph.D. in Economics from the University of Minnesota and a Ph.D. in Mathematics from Universidad del Pais Vasco. He was Assistant Professor at the State University of New York (Stony Brook) and Visiting Professor at the graduate schools of Yokohama University and Keio University. He has been President of the Spanish Economic Association and chairman of FEDEA (Fundación de Estudios de Economía Aplicada, Madrid). He has published in Econometrica, Journal of Economic Dynamics and Control, Journal of Macroeconomics, International Journal of Forecasting, Journal of Forecasting, Journal of Time Series Analysis, Journal of Banking and Finance, Economic Modelling, European Journal of Operations Research, Computational Economics, Computational Statistics, Journal of International Financial Institutions, Markets and Money, International Journal of Moneyand Finance, Journal of Fututrs Markets, Applied Financial Economics, Applied Economics Letters, Quarterly Review of Economics and Finance, Quarterly Journal of Finance, Quantitative Finance, Journal of Risk and Financial Management, and International Journal of Finance, and he has contributed with chapters to several books on Macroeconomics and Econometrics. He is the author of Econometria and Estadistica y Econometría, both textbooks edited by McGrawHill in Spanish. His research interests include Economic Policy Evaluation and Financial Econometrics. Esther Fernández is Associate Professor of Economics at the Department of Quantitative Economics at Universidad Complutense (Madrid). Her Ph.D. dissertation was selected as the best doctoral dissertation in Economics at Universidad Complutense in 1999. Her research interests include Monetary Theory, Economic Growth, and Environmental Economics. She has published at Journal of Economic Dynamics and Control,Energy Policy and Economic Modelling, and Spanish academic journals. Jesús Ruiz is Associate Professor of Economics at the Department of Quantitative Economics at Universidad Complutense (Madrid). He obtained his Ph.D. in Economics from Universidad Complutense in 1997. He has published in Journal of Economic Dynamics and Control, Energy Journal, Energy Policy, International Review of Economic and Finance, Economic Modelling, Journal of Macroeconomics, Empirical –Economics, Applied Financial Economics, Spanish Economic Review and other Spanish journals, and he has contributed with chapters to books on Computational Economics. His research interests include Economic Policy Evaluation in Dynamic Macroeconomic Models and Environmental Economics.