Thank you, Gianluca, and thank you for the opportunity to speak to you today.1 Let me begin by recognizing the Department of Economics at Princeton for its history of nurturing and supporting scholars in reaching their full potential. Some of the most important, transformative conversations I have had in my career have happened on this campus and with economists making significant contributions to the field. Let me start with the last time I was here. When I was a post doc at Stanford, I emailed Alan Krueger out of the blue and attached an early version of a new paper, asking him if he would meet with me for an hour ... (full story)