About 4 percent of men may unknowingly be raising a child that really belongs to the mailman or some other guy, researchers speculate in a new study. Here's the real news: With modern methods, the truth will become known more frequently. Researchers pawed through a host of scientific articles published around the world from 1950 through last year. The perceived "paternal discrepancy rate," as it is called, ranges from less than 1 percent to as high as 30 percent in the various studies. Most researchers believe the rate is less than 10 percent. The author's settled on four percent --...