A social scientist at the University of Chicago shows that the only investment advice you need to know can all fit in the palm of your hand.

I'm an individual self-taught investor who has just lost a LARGE sum of money investing in a company whose stock (of course) went immediately downhill after I bought it. Rather than becoming afraid of stocks, I am sure there is a lesson to be learned here. I'm just not sure what it is. What tips could you give for people who lose large amounts of money but want to keep investing? Brian, Miami, FL