If you want to know what's going on in the U.S. housing market, chances are you follow the Case-Shiller index. Robert Shiller, the Yale University economist who helped create the home-price gauge, was something of a pop economist even before the real estate meltdown—a book published in 2000 warning about the coming crash in stocks made him a rock star of the last bubble, too. His latest book, Animal Spirits: How Human Psychology Drives the Economy, and Why It Matters For Global Capitalism, was written with Univeristy of California, Berkeley economist George Akerlof. Shiller spoke with TIME's Barbara Kiviat.