Moving Average Ratio and Momentum

August 26, 2010

A few months ago I had a post about the Momentum Echo (click here to read the post). I ran across another relative strength (or momentum if you prefer) paper that tests yet another factor. In Seung-Chan Park’s paper, “The Moving Average Ratio and Momentum,” he looks at the ratio between a short-term and long-term moving average of price in order to rank securities by strength. This is different from most of the other academic literature. Most of the other studies use simple point-to-point price returns to rank the securities.

Technicians have used moving averages for years to smooth out price movement. Most of the time we see people using the crossing of a moving average as a signal for trading. Park uses a different method for his signals. Instead of looking at simple crosses, he compares the ratio of one moving average to another. A stock with the 50-day moving average significantly above (below) the 200-day moving average will have a high (low) ranking. Securities with the 50-day moving average very close to the 200-day moving average will wind up in the middle of the pack.

In the paper Park is partial to the 200-day moving average as the longer-term moving average, and he tests a variety of short-term averages ranging from 1 to 50 days. It should come as no surprise that they all work! In fact, they tend to work better than simple price-return based factors. That didn’t come as a huge surprise to us, but only because we have been tracking a similar factor for several years that uses two moving averages. What has always surprised me is how well that factor does when compared to other calculation methods over time.

The factor we have been tracking is the moving average ratio of a 65-day moving average to the 150-day moving average. Not exactly the same as what Park tested, but similar enough. I pulled the data we have on this factor to see how it compares to the standard 6- and 12-month price return factors. For this test, the top decile of the ranks is used. Portfolios are formed monthly and rebalanced/reconstituted each month. Everything is run on our database, which is a universe very similar to the S&P 500 + S&P 400.

 Moving Average Ratio and Momentum

(click to enlarge)

Our data shows the same thing as Park’s tests. Using a ratio of moving averages is significantly better than just using simple price-return factors. Our tests show the moving average ratio adding about 200 bps per year, which is no small feat! It is also interesting to note we came to the exact same conclusion using different parameters for the moving average, and an entirely different data set. It just goes to show how robust the concept of relative strength is.

For those readers who have read our white papers (available here and here) you may be wondering how this factor performs using our Monte Carlo testing process. I’m not going to publish those results in this post, but I can tell you this moving average factor is consistently near the top of the factors we track and has very reasonable turnover for the returns it generates.

Using a moving average ratio is a very good way to rank securities for a relative strength strategy. Historical data shows it works better than simple price return factors over time. It is also a very robust factor because multiple formulations work, and it works on multiple datasets.

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One-Trial Learning

August 26, 2010

It’s well known in psychology that one-trial learning can be created if the stimulus is aversive enough. For example, a child that puts down their hand on a hot stove typically will never do it again. Maybe that is part of what is happening with the stock market right now.

According to a recent article in the New York Times, investors are acting differently toward the stock market recovery this time around.

After past recessions, ordinary investors have typically regained their enthusiasm for stocks, hoping to profit as the economy recovered. This time, even as corporate earnings have improved, Americans have become more guarded with their investments.

“At this stage in the economic cycle, $10 to $20 billion would normally be flowing into domestic equity funds” rather than the billions that are flowing out, said Brian K. Reid, chief economist of the investment institute. He added, “This is very unusual.”

Investors have been buying so many bonds that there has been unrelenting talk about a “bond bubble.” I’m not sure that investors are actually interested in bonds; I think the emotional drivers may be more complicated.

Surveys over the years have shown that most retail investors do not even understand that bond prices and interest rates are inversely related. It’s not unusual to find an investor that thinks the U.S. is headed for inflation down the road, but is still happily buying bonds right now. Maybe I am incorrect in my assumption, but I don’t think the average person managing their own 401k plan is paying close attention to all of the economic arguments about the prospects for inflation or deflation. They just aren’t that sophisticated. I think they are buying bonds because 1) they got burned in stocks and want out, and 2) bonds are pretty much the only other investment option they know about.

In other words, it may be that investors are simply removing their hand from the stove (stocks). Because their knowledge about financial instruments is so limited, however, there is a potential danger of going from the frying pan to the fire.

Bonds are simply loans. If all goes well, you get your money back with interest. Bonds might hold their market value in a deflationary or slow growth environment, although a slow economy might actually increase the chances of default. Bonds are not growth instruments.

All great fortunes, on the other hand, depend on growth. Entreprenuers that start a company that grows sometimes become wealthy. Real estate fortunes are made using leverage—and growth in the underlying property values or their cash flows. Stock market fortunes have been made through canny ownership of equity securities. Off the top of my head, I can’t think of any fortunes that have depended on buying loans.

In their rush to run away from pain, many investors have, perhaps unwittingly, also run away from growth. Believe me, I understand the appeal of bonds right now. Every investor has taken plenty of lumps over the past few years. Yet the only way I see for investors to successfully prepare for retirement involves exposing a significant part of the portfolio to growth.

There are a couple of ways to accomplish that. One could construct a strategic allocation with some growth exposure, or you could look to a tactical portfolio that owned growth investments when equity market conditions were strong and owned other assets when equity market conditions were not conducive. Such a portfolio need not be limited to stocks and bonds; it could include other asset classes such as commodities, currencies, and real estate. This flexibility in tactical asset allocation was the driving idea behind our Global Macro portfolio. A portfolio that rotates systematically toward strong asset classes has the ability to profit during strong trends and the potential to reduce capital risk in poor equity environments. To our way of thinking, a flexible solution is superior to a knee-jerk reaction to exit all growth investments.

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The Overwhelming Power of Supply and Demand

August 26, 2010

King Canute famously (and unsuccessfully) commanded the tide not to come in to demonstrate to his sycophantic followers that he really didn’t have the power to alter the course of nature. It would be worthwhile for the U.S. government to learn that lesson.

The Economist had a short blog piece on July new home sales. In this case, a picture is worth a thousand words.

(click to enlarge) Source: The Economist, Calculated Risk

This is a long-term view of new home sales going back into the early 1960s. You can see that there was cyclical variation between about 400,000 and 800,000 units for many years during the baby boom. In the late 1990s, for whatever reason, home sales took off. Maybe demand for homes was actually higher between the aging baby boomers and new echo boomers just going into the housing market, or maybe it was just real estate speculation-it doesn’t really matter. Demand was huge and housing boomed.

After demand was satiated, the market peaked around 2006 and has since been in a steady decline. Although the boom was encouraged, the decline on the flip side has been considered a bad thing by the government. In 2009, the U.S. government approved a large national stimulus package to revive the overall economy and a significant new housing tax credit to specifically encourage home purchases.

On the chart, the intervention effect of the largest global economic superpower in history can be seen as the small recent blip around the 400,000 unit area. As soon as the artificial stimulus was ended, new home sales resumed their decline. Some economists look at this as evidence that we need more stimulus. I look at it as evidence that the market is going to find the equilibrium point between supply and demand sooner or later, whether the government interferes or not. If prices continue to fall and housing becomes a bargain versus renting, unit sales will probably rebound more quickly than if demand is temporarily manipulated by intervention.

That’s how free markets, including the stock market, are supposed to work. Markets are price discovery mechanisms for finding the equilibrium point for supply and demand. Price discovery is a natural process of markets. Relative strength allows an investor to identify those areas where demand is in control of the situation, although one never knows exactly how long it will last. By systematically rotating toward relative strength, an investor over time may have the opportunity to earn outsized returns. King Canute knew that you needed to go with the flow and market participants would do well to heed that lesson today.

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Fund Flows

August 26, 2010

The Investment Company Institute is the national association of U.S. investment companies, including mutual funds, closed-end funds, exchange-traded funds (ETFs), and unit investment trusts (UITs). Members of ICI manage total assets of $11.82 trillion and serve nearly 90 million shareholders. Flow estimates are derived from data collected covering more than 95 percent of industry assets and are adjusted to represent industry totals.

No surprise in fund flows for the week ending 8/18/10 as another $6.5 billion in new money went to taxable bond funds while other asset classes either had modest inflows or outflows. For the year, taxable bond funds have attracted nearly $179 billion in new assets. Domestic equity funds are at the bottom of the ranks, with nearly $39 billion in redemptions.

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