This could include employing dollar-cost averaging or automatically rebalancing your portfolio when particular asset classes gain or lose value in comparison to others.

FORBES: The Irresistible Nature of Trading

Dollar cost averaging gradually adds to or removes from an investment, ensuring that you never purchase your full position at a high or sell it at its low.

FORBES: Making Volatility Work For You

Dollar-cost averaging forces us to do what doesn't come naturally, or as Mr. Malkiel puts it, "exactly what our emotions tell us not to do" buy more shares when prices are low and fewer when prices are high.

WSJ: How Investing Dimes Can Beat Dollars