Paul Krugman: I often think of labor economics as a role model for the field: a subfield in which theory is disciplined by evidence and (most) researchers are willing to listen to that evidence even when it challenges their preconceptions. And hardly anyone does modern labor economics as well as UMass Amherst’s Arindrajit Dube, who has an excellent new book out. I talked with him about that book and the state of labor more generally.