The authors thank Kay Giesecke, an anonymous associate editor, and two referees for valuable input. The authors received helpful comments and suggestions from Caio Almeida, Federico Bandi, Tony Berrada, Svetlana Brizlagova, Federico Carlini, Ines Chaieb, George Constantinides, Jerome Detemple, Patrick Gagliardini, Eric Ghysels, Lars Hansen, Oliver Linton, Stefan Nagel, Paolo Porchia, Olivier Scaillet, Paul Schneider, Andrea Vedolin, Michael Weber, Dacheng Xiu, and Paolo Zaffaroni.