Harry Markowitz’s Two Intellectual Children: Mean–Variance and Behavioral Portfolio Theories
回顾了马科维茨1952年提出的均值-方差投资组合理论和行为投资组合理论，对比了整体投资组合与心理账户投资组合的差异，指出两者均位于均值-方差有效前沿上。
In 1952, Harry Markowitz gave birth to two intellectual children. In one, he built mean-variance portfolio theory. In the other, he provided a building block for behavioral portfolio theory. Mean–variance investors consider their portfolios as a whole, considering only their overall risk and expected returns. They choose portfolios on the mean–variance efficient frontier, with combinations of risk and expected returns that are best for them by their overall risk tolerance and desire for overall expected returns. Behavioral investors consider their portfolios as collections of mental accounts, each with a goal, such as education, retirement, and bequest. They might be willing to tolerate high risk in their bequest mental account, expecting high returns; medium risk in the retirement mental account, expecting medium returns; and only low risk in their education mental account, expecting low returns. Yet each of the three mental accounts and also the overall portfolio lie on the mean–variance efficient frontier.