Alan Greenspan coined the phrase "irrational exuberance" in late 1996 to describe the rapid growth in the stock market. Professor Robert Shiller, an economist at Yale, has written a book by the same title (should I say he's a bear?). Actually, exuberance, rational or otherwise, is a characteristic of behavioral economics and finance. Daniel Kahneman shared the 2002 Nobel Prize in Economics for his work in the area. Start by reading a short piece from CFO.com (http://www.cfo.com/printable/article.cfm/3014027?f=options) and look elsewhere as you are interested. My question is: how do behavioral considerations impact the way we are doing valuation?