Guest Blog Post by Professor Tom Scott, Sweet Briar College
During the fall semester at Sweet Briar College, a school noted for its physical beauty, educational excellence, and experiential learning, my "Principles of Investments" class became involved in an experiment that will be tracked transparently via the Internet in 2010. During this class, the students' primary project was to develop a rule-based decision framework for the selection of stocks.
In this class of 11 students, I had two teams of three students; one team of two students; and three students who elected to work individually. Of the six models presented (some being composite models), five will be tracked on the internet during the upcoming semester and compared to the results of the S&P 500 and the Dow Jones Industrial Average. The objective of the experiment is to determine how rules developed by students with little or no background in investment strategies compare to the best minds on Wall Street. As mentioned, the rules for each strategy will be laid out transparently on the Web and the stock picks for each month will be posted by the 5th of each month (we are working on the statistics compilation lag). Because the rules are completely transparent, the results will be reproducible to anyone with access to historic stock information.
Who are the women developing the models and what is their background?
The students developing the model are primarily undergraduate juniors and seniors majoring in either Business Management or Economics. While some of the students have had more advanced math courses, their educational background in finance and investments was limited to one undergraduate finance course. Below are the nine students whose models will be tracked over the course of 2010.
Michelle Anderson, SR, Economics Major with Business Minor, from San Diego, CA
Lindsey Davis, SR, Biology Major with Chemistry and Business Minor, from Beaverdam, VA

Hannah Hesser, SR, Business Major with Math and Statistics Minor, from Midlothian, VA
Laura Jett, SR, Math Major with Statistics and Business Minor, from Littleton, CO
Andrea Jones, SR, Business Major with Spanish Minor, from Amherst, VA
Brittany Lindsey, SR, Biology Major with Business Minor, from Fairfax, VA
Heather McPheeters, SR, Business Major, from Columbia, SC (pictured at left)
Jennifer Young, JR, Business Major, from Mechanicsville, VA
Morganne Young, JR, Business Major with German Minor, from Hebron, CT
How did the class expose the students to investment strategies?
For the first several weeks of class, the students were exposed to the costs and benefits of rule-based strategies applied to several professional disciplines, largely through
"The Naked Portfolio Manager" written by thought-leader Robert Fischer. Fischer's book describes, and cites specific applications of, successful rule-based decision-making frameworks in medicine, law, education, and other disciplines. He further proposes that similar rule-based strategies applied to Wall Street should provide better, more consistent results over time than individual brokers and investment advisors attempting to apply their own knowledge and reasoning filter to the millions of pieces of new data available daily. To complicate matters, those same brokers and advisors are subject to the myriad of human thinking errors to which we are all exposed.
During the second stage of the class, I encouraged students to review some of the rules set forth in books such as Matson and Hardy's "
Data Driven Investing" and O'Shaughnessy's
"What Works on Wall Street," and to investigate the philosophy of rule-based models like the Redline Strategy, developed by Richard Cripps and Tim McCann, analysts at
Equity Compass Strategies. This allowed the students to see how Fischer’s rule-based strategies might be applied on Wall Street. As the class proceeded, students began to understand the logic behind rule-based decision-making, and began to develop their own thoughts about the rules set forth in their reading.
How did the students develop their models?
After becoming familiar with rule-based decision-making and its potential application to Wall Street, I asked the students to experiment with the high-level rules they had developed so they could begin to define concrete rules that we could back-test. In order to get a feel for relative returns, I referred the students to
http://www.stockscreen123.com/. This site allows the development of rules against which theoretical back-tests can be run and compared to a baseline return, such as the S&P 500.
The purpose of this experiment was not to gain precise results for exact strategies, but rather to compare at a higher level some basic strategies such as small market cap vs. large market cap returns; small PE ratio vs. large PE ratio returns; PE ratio vs. PS ratio returns; cash flow vs. earnings as selection criteria; Best in Industry vs. Best in Sector criteria; and so on. The site allows the user to build screening criteria using a rule wizard and also through the development of free form rules that can be developed from the hundreds of individual pieces of information available. The use of
http://www.stockscreen123.com/ allowed the students to develop specific rules they would test using actual data. The students were encouraged to develop multiple potential models in case the back-tests using actual data resulted in a difference in performance.
The final step in the class was to back-test the models the students developed. Tim McCann provided the students with nine sets of data, each containing one year’s worth of information. And although only month-end data provided, the students stared glassy-eyed at nine files, each of which contained about 35,000 rows and 200 columns of information. Each row of the file was dedicated to one stock and the month end data for that stock. This included not only the ticker symbol, the opening and closing price, the monthly high and low, and so on, but many variables concerning the financial fundamentals of the company, key ratios, trend variables, future earnings and sales estimates, and more. This step, more than any other, demonstrated Fischer's assertion that there is often too much information for even the human brain to process effectively.
After the students overcame their initial data shock, we discussed how to effectively handle the seven million data points staring them in the face for each year. We also discussed at a high level some of the other factors that may influence stock selection for those not using rule-based methods. In addition to the millions of data points that can be combined in a near infinite number of ways, there are press conferences, news releases, conference calls, charismatic CEOs, whispers on the street, earnings announcements, influential bloggers, loud pundits, and so on that can influence thinking.
The students then spent two to three very long weeks back-testing their rules. After meeting with mixed results, the students presented their models between December 10th and 20th. The rules they have elected to pursue are shown below.
Jenny Young (The Young Models)
Young Model 1 (20% of portfolio)
Market Cap: $100 million
PE Ratio: Lowest 40% in the Market
Improved sales growth and operating margins: Highest 30% in the Market
Decreasing # of re-purchased shares over the past 3 years: Highest 20% of decline in Market
Rebalance every 4 weeks
Young Model 2 (60% of portfolio)
Market Cap: $100 million
PE Ratio: Lowest 10% in the Market
PS Ratio: Lowest 20% in the Market
PEG Ratio: Lowest 20% in the Market
Rebalance every 4 weeks
Young Model 3 (20% of portfolio)
Market Cap: $100 million
Improved sales growth and operating margins: Highest 20% in the Market
Highest Dividend Growth Rate over past two years: Highest 15% in the Market
Decreasing # of re-purchased shares over the past 3 years: Highest 20% of decline in Market
Rebalance every 4 weeks
Heather McPheeters, Andrea Jones and Brittany Lindsey (the HAB Model)
HAB Model
PE Ratio: Greater than 0 and Lowest 20% in the Industry
Low Short Interests: Lowest 20% in Industry
Market Cap: $250 Million
Hannah Hesser, Michelle Anderson, and Laura Jett (the HML Model)
HML: Model 1 (40% of portfolio)
PE Ratio: Greater than 0 and Lowest 20% in Industry
Dividend Yield: Highest 20% in INdustry
HML: Model 2 (60% of portfolio)
Market Cap: Less than $250 Million
PE Ratio: 0 and Lowest 30% of Market Sector
PEG Ratio: In the Lowest 40% of Market Sector
Morganne Young (The Gibby Model)
Market Cap: $250 Million
PE Ratio: 0 and in Lowest 20% of Market Sector
PS Ratio: In Lowest 20% of Market Sector
PCF Ratio: 0 and in Lowest 20% of Market Sector
PBV Ratio: 0 and in Lowest 20% of the Sector
Lindsey Davis (The LMD Model)
PE Ratio: 0 and in Lowest 40% in Industry Sector
PCF Ratio: 0 and in Lowest 40% in Industry Sector
Market Cap: $750 Million
How will results be tracked and reported?
I will track each of these models monthly, attempting to provide the stocks selected by the 7th of each month. At that point, results from the prior month will also be posted. I am working to shorten that process to better reflect real-time decisions. Results will be tracked based on the assumption that the stocks selected based on each rule will be purchased at the beginning of the month.