Stocks found more downside Thursday morning, as the turned negative on the year.
So if one fears more losses ahead, what's an investor to do?
One option would be to allocate more of one's portfolio to stocks that don't tend to move in lockstep with the market.
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The traditional gauge of how much a given stock is levered to the overall market's moves is a metric known as "beta." By operating on the correlation between the moves of a stock and a relevant index (most commonly the S&P 500) and the average magnitude of the stock's and the index's moves, beta tells an investor roughly how much she is exposed to the index as a whole through that given stock.
Generally, higher-beta names will be stocks that are either very volatile, or highly levered to the overall economy—high-end retailers, semiconductor stocks, homebuilders and the like. Meanwhile, low-beta stocks march to the beat of their own metaphorical drum.
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Such is the case for the three S&P 500 stocks with betas of just about zero: Newmont Mining, Southern Co. and ConEd.
Over the past three years, these companies have enjoyed no real relationship with the overall index, based on a five-year examination of monthly returns.
Perhaps the most surprising of the three is Newmont. People generally think of low-beta stocks as quiet and boring, but the gold miner is highly volatile; Newmont has lost more than two-thirds of its value in the past five years, and was jumping some 4 percent on Thursday alone.
The reason its beta is so low, and in fact subzero according to FactSet, is that it enjoys no correlation with the S&P as a whole. Gold miners tend to follow gold in zagging when the market zigs.
Meanwhile, utility companies Southern and ConEd are classic rate plays, with dividend yields of 4.7 percent and 3.8 percent, respectively. This means they are much more interested in what's going on in the bond market, which can also move inversely to stocks.
Of course, just because a stock hasn't been correlated to the overall market in the past does not mean that the relationship will hold into the future. In extremely trying times, correlations are infamous for rising due to contagion risk.
More generally, investors have historically proven to be better off when they ignored their worst instincts of fear and greed and stuck to a sensible asset allocation in good times and bad.
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"I strongly advise investors not to buy a stock on the premise that the market will go lower," stock picker Eddy Elfenbein of the Crossing Wall Street blog wrote to CNBC.
Still, on Thursday morning, Newmont, ConEd and Southern were all in the green as the overall market slides.
