Portfolio Optimization Theory Versus Practice

Nearly all investment professionals rely upon portfolio optimization techniques grounded in Modern Portfolio Theory to structure investment portfolios for individual investors. Using statistical techniques and computer-assisted modeling, investment advisers are able to combine different types of assets such as stocks, bonds, cash, real estate, and hedge funds to create portfolios that claim to offer the best possible return for specified level of risk, or to minimize the amount of risk an investor must assume to achieve a specified amount of return. The problem is that the real world does not always fit the theory perfectly. Sometimes, reality and theory are not even close.