What’s the biggest challenge for investors these days? Macroeconomic risk? The threat of war in the Middle East? Slow economic growth? A collapsing euro? One can argue that the explosion of information and advice (much of contradictory) is the number-one hazard for thinking clearly and designing a portfolio that will succeed over the medium- and long-term horizons. What’s the antidote to the noise that permeates our digital world? It starts by considering the major asset classes and a benchmark of these betas, such as the Global Markets Index that’s routinely updated on these pages.