"We're going through something very similar in real estate that we did with stocks," said Robert J. Shiller - a professor of economics at Yale, whose prescient book on stocks, "Irrational Exuberance" (Princeton University Press, 2000), appeared just a few months before technology stocks began their slide. "It's driven by the same forces: that investments can't go bad; that it has the potential to make you rich; that you'll regret it if you don't do it; that it looks expensive but is really not."