Janet Yellen Is No Stock Market Sage

At a recent International Monetary Fund event in Washington, D.C., Federal Reserve Chair Janet Yellen opined about the â??potential dangersâ? posed by â??quite highâ? stock market valuations. This was not her first market prognostication. In July 2014 she singled out biotech and social-media stocks as having â??substantially stretchedâ? valuations. Such comments are ill considered and are more likely to do harm than good.