In an interesting study conducted at the Vanguard Group, they claim that during the financial crisis of 2008 and 2009, among the 2.7 million people with I.R.A.’s at Vanguard, men were much more likely than women to sell their shares at stock market lows.

If there is any truth in this data that says women make better decisions around investing - what is it?  Can science provide some answers as to why men lag behind women when it comes to making smart investing decisions?

Could it be the way the male/female brain is built? Is is purely a behavioral difference? What does testosterone have to do with making investment decisions? Does brain imaging technology give us any answers? What might evolution have to do with it?

In this new study by the Vanguard Group, they show some interesting results along with answers that may surprise you. Check out the study in the New York Times article titled How Men's Overconfidence Hurt's Them as Investors.