1. Graduate School of Business, Stanford University, Stanford, California 94305-5015;
2. INSEAD, Fountainbleau Cedex, 77305 France;
3. School of Management, Yale University, New Haven, Connecticut 06520;
4. Anderson School of Management, University of California at Los Angeles, Los Angeles, California 90048;
5. College of Business, Arizona State University, Tempe, Arizona 85287;