This article in Business Week reviews the star rating changes for 7 companies. YUM, (which is Taco bell/Pepsi) Prudential, Home depot, Career Education, Advanced Micro devices, Agilent Technologies and MedImmune. The S&P star rating change is associated with analysts' opinions to either, buy, hold, or accumulate stock. The analysts are basing their opinions on the predicted P/E ratios in comparison to peers within the industries as well estimated future (2003 & 2004) revenues as well as estimated future earnings.