On Wall Street, you need any edge you can get, especially when it comes to deciphering which stocks to sell (and when). Some may turn to advanced solutions such as high-frequency trading algorithms. Others turn to oddball ideas, such as deciphering magazine covers. It’s not as irrational as it may initially sound. For example, sports fans know about the Madden video game cover curse. Basically, NFL stars that are celebrated on the cover of the popular gaming title encounter an injury or some other misfortun ...