While stock correlations have been declining, several researchers say that doesn’t make the current environment any better for stick pickers — whose odds of success remain exceptionally low.
“One factor that has a big effect on stocks’ sensitivity to movements in the overall market: changes in the market’s overall volatility, as measured by benchmarks like the Chicago Board Options Exchange’s Volatility Index,” Mark Hulbert writes in a recent MarketWatch column. ” Yet those fluctuations don’t mean there has been any real change in stocks’ relationships to the overall market, according to Kristin Forbes, professor of management and global economics at MIT’s Sloan School of Management. ‘It’s an artifact of the statistics that any time volatility decreases, correlations decrease automatically as well,’ she says.”
Hulbert adds that, “in addition to low market volatility recently, another reason why stocks have been acting more independently of late is that the pendulum has swung so far away from the fear end of the spectrum.” As fear increases, stocks tend to move more in sync with each other, he says. “The investment implication: Stocks — at any time and with no warning — could once again begin moving in lock step with the overall market. As a result, stock selection has no greater odds of success now than at any other time.”
Unfortunately, those odds are quite poor, he says. One researcher tells Hulbert that “less than 1% of individuals who trade frequently can consistently outperform the market through skill. Over the long run, the rest would be better off investing in low-cost index funds benchmarked to the broad market.”