Long-Short Factor Investing

Factors can be captured via both long-only and long-short investing approaches. See which key considerations can determine the right strategy.

In Perth, Australia, where I grew up, swimming pools and beaches are an important part of the lifestyle. Kids learn to swim in school and I still remember being proud when I was awarded my Junior Swim and Survive certificate! I’ve enjoyed swimming ever since. And yet it was only after I took up scuba diving that I realized what a completely different experience it is to swim under the surface observing fish and coral reefs from inches away.

Factor investing is like that. I think of long-only as swimming with my head above the water. Long-short investing, which seeks to take advantage of factor risk premiums in a new dimension, is akin to a scuba diver traveling under the water. You need specialized equipment and skills to go scuba diving, just as investing long and short simultaneously requires a very different perspective.

The long and short of it

Factor investing involves pairs: for every stock that has positive factor attributes, there must be a stock on the other side. For every value stock that is cheap relative to its intrinsic value, there must be a stock that is relatively expensive. For every firm producing high-quality earnings, there is a firm with more volatile, less cash flow–based earnings. For every name trending up, there is a name trending down.

Long-only factor investing involves taking just one side and tilting the portfolio toward stocks exhibiting factors such as value, quality and momentum. Long-short factor investing allows investors to play both sides: going long value, short growth; long high quality, short junk; and long winners, short losers.

When should investors consider one strategy versus the other?

Relative return or absolute return?

First, the most critical decision is what you want to achieve.

  • Relative return strategies track a benchmark, like the S&P 500 Index, with the aim to outperform that benchmark.
  • Absolute return strategies are not compared to an asset-class benchmark and seek to generate a diversifying source of return.

Let’s use the value factor as an example.

A long-only smart beta value strategy has historically outperformed the market over the long run. But, holding a long-only value portfolio still retains a significant amount of broad equity exposure, even as it seeks to enhance returns relative to a market-capitalization index.

A long-short value strategy simultaneously holds long positions in the cheapest stocks while shorting the most expensive stocks. This is done with the aim of removing aggregate market exposure. The same strategy can be implemented across asset classes—going long cheap securities and short expensive securities in equities, fixed income and commodities. Thus, long-short factor strategies may be appropriate for an alternative allocation in an investor’s portfolio. Although it is important to note that long-short investing comes with some significant risks and is not suitable for all investors.