This Is How You Know When the Stock Market Is in a Bubble

One of the most fascinating market phenomenons is the bubble. When they occur, fortunes are made and lost, and the full spectrum of human emotions, from fear to greed, are on display. But what defines a bubble exactly, and how do you know when you're actually seeing one? This week on Odd Lots, we speak with Harvard Business School economist Robin Greenwood, who has figured out the key characteristics that all stock market bubbles have in common.