Do Physician Investors and/or their Financial Advisors Use and Abuse Modern Portfolio Theory?

Join Our Mailing List

The Cultural Clash of Passivity versus Activity

By Dr. David Edward Marcinko MBA CMP™


Ninety-three year old Professor Harry Markowitz PhD, coined the phrase “modern portfolio theory” [MPT] and concluded that investors are rewarded for taking certain risks but may not get rewarded for taking others. He developed the notion of an “efficient frontier” for different groups of asset classes and the idea that the higher the expected return, the higher the risk.

The Brinson, Hood, Beebower Study

In their 1986 study, Brinson, Hood, and Beebower attempted to measure three investment activities: (1) asset class selection, (2) market timing, and (3) security selection. They concluded that asset class selection had, by far, the greatest effect on the risk/return characteristics of a portfolio (some 93.6% of performance). But the most startling conclusion was that, if left alone, investment policy would have produced a higher average return than when market timing and security selection were taken into account. These latter factors actually reduced the average return over a 10-year period.

The Fama & French Study

In 1982, Fama and French found that three factors—market exposure, company size, and “value”—were systematic risks that explained the vast majority of equity market returns. “U.S. small-cap value stocks” is therefore a discreet asset class possessing all three of these systematic risks.

Most physicians and financial advisors are aware of modern portfolio theory but some fail to apply the principles to actual investor situations. Three examples: (1) using erroneous asset-class definitions, (2) using actively managed funds, and (3) relying on market timing. The abuse of modern portfolio theory can create portfolios loaded with latent risks that, on the surface, appear benign.

Not all Agree

Not everyone is in agreement with modern portfolio theory. Some detractors agree in principle, recognizing, for example, that “value” stocks have had higher returns than “growth” issues but they cite the cause as “mispricing” rather than risk.


Institutional investors have gradually increased their commitment to passive strategies from virtually zero 20 years ago to 30% or more in the last decade [Think: Vanguard].

Individual and physician investors, on the other hand, have less than a 5% commitment.

Note: “Modern Portfolio Theory: Fact or Fiction?,” Gerard F. Stellwagen and Robin P. LaCouture, NAPFA Advisor, July 1997, pp. 1–7, National Association of Personal Financial Advisors for Fee-Only Financial Advisors.


Your thoughts and comments on this ME-P are appreciated. Feel free to review our top-left column, and top-right sidebar materials, links, URLs and related websites, too. Then, subscribe to the ME-P. It is fast, free and secure.


Speaker: If you need a moderator or speaker for an upcoming event, Dr. David E. Marcinko; MBA – Publisher-in-Chief of the Medical Executive-Post – is available for seminar or speaking engagements. Contact:


FINANCE: Financial Planning for Physicians and Advisors
INSURANCE: Risk Management and Insurance Strategies for Physicians and Advisors

Product DetailsProduct DetailsProduct Details

Product Details  Product Details

   Product Details 

%d bloggers like this: