Objective research and reviews to aid investing decisions
How do the typical portfolio and performance of self-directed investors differ from those of investors who employ financial advisors? Do financial advisors systematically add value by providing information to, and tempering the irrationalities of, individual investors? In his March 2008 paper entitled "The Influence of Financial Advice on Individual Investor Portfolio Performance", Marc Kramer compares the investment portfolio content and performance of advised and self directed investors in the Netherlands. Using portfolio data for a diverse mix of 15,675 individual Dutch investors over the 52-month period from April 2003 to August 2007, he concludes that:
The following chart, taken from the paper, depicts the average asset mixes of self-directed and advised investors based on equal weighting of individual portfolios. Both groups concentrate on stocks and bonds, but self-directed investors choose riskier stock-bond allocations (70%-22%) compared to advised investors (50%-42%). Turbos are leveraged, derivative-like investments.

It seems that advised investors in this sample might well outperform self-directed investors on a raw basis during bearish periods.
In summary, on a risk-adjusted basis, diverse groups of self-directed and advised investors perform about the same, with alphas close to zero.
For related research, see Blog Synthesis: Individual Investing and Blog Synthesis: The Wisdom of Analysts, Experts and Gurus.