Gang Gong is Associate Professor of Economics and Management at Tsinghua University in Beijing, China, and co-author of The Forces of Economic Growth (2005). Willi Semmler is Professor of Economics at New School University, at the Center for Empirical Macroeconomics at Bielefeld University, and Research Fellow at the Bernard Schwartz Center for Economic Policy Analysis. He is the author of Asset Prices, Booms, and Recessions (2003), co-author of The Forces of Economic Growth (2005), Dynamic Macroeconomics (1997), Disequilibrium, Growth, and Labor Market Dynamics (2001), Monetary and Fiscal Policy in the Euro-area (2005); editor of Monetary Policy and Unemployment: US, Euro-Area and Japan, (2005) and co-editor of the series Dynamic Modelling and Econometrics in Economics and Finance.