Comprehensive Study Notes on Mutual Fund Returns and Biases

Introduction to Mutual Fund Returns

  • Mutual funds often present outstanding performance returns in advertisements.
  • Notably, it is rare to see advertisements featuring poor performance results.
  • This phenomenon raises questions about the actual performance of mutual funds and what happens to underperforming funds.

Survivorship Bias in Mutual Funds

  • Definition: Survivorship Bias

    • Occurs when only the successful funds are accounted for in reports, while unsuccessful funds are excluded.
    • This skews statistical data, suggesting that only winning funds exist.

  • Mechanism of Survivorship Bias:

    • Poor-performing funds are either closed or merged into better-performing funds.
    • This leads to a perception that mutual fund companies consistently generate positive returns.

  • Case Example:

    • Post dotcom crash, many underperforming Internet funds were merged into larger technology funds.
    • The negative performance history of the merged funds was effectively erased from financial reports.
    • Result: Investors may be misled to believe that performance is better than actual.

  • Statistical Findings:

    • Study by Mark Carhart (Journal of Finance, March 1997):
    • Reports that by 1993, one-third of mutual funds had disappeared.
    • Wall Street Journal (1997):
    • Mutual funds reported average returns of 18.1% during 1982-1992.
    • When considering survivorship bias, this average decreased to 16.3%.
    • This return was lower than the S&P 500's return of 17.5% during the same period, indicating underperformance in mutual funds when adjusted for survivorship bias.

Hedge Funds and Survivorship Bias

  • Hedge funds experience similar challenges with survivorship bias.
  • Research Firms:
    • Data on retired hedge funds started being collected only in 1994.
    • Thus, previous performance statistics before this date may significantly reflect survivorship bias.

Ethical Implications of Reporting

  • Question: Should mutual fund companies be allowed to exclude poorly performing funds in reporting?
  • Argument Against Exclusion:
    • Analogous to car buyers; they can't erase past accidents. Therefore, mutual funds should not hide their historical poor performance.
  • The Association for Investment Management and Research (AIMR):
    • Attempts to implement reporting restrictions on past performance, yet compliance is not mandated.
  • Practical Compliance:
    • Even compliant companies often place the true performance in fine print, which many investors neglect.

Creation Bias

  • Definition: Creation Bias
    • A variation of survivorship bias present during the fund's launch phase.
    • Investment managers are given a small fund for a trial period.
  • Fund Selection:
    • After a designated time, only the managers with the best performance can continue to offer their funds to the public.
    • Poor performers are discontinued without fanfare, and thus do not influence perceived performance statistics.
  • Growing Concern:
    • Some investment professionals argue that creation bias is becoming more problematic than survivorship bias, primarily due to its subtlety.

Conclusion on Mutual Fund Investments

  • John Bogle, founder of Vanguard, promoted the idea that index funds are the most reliable investment option in mutual funds.
  • Index funds are characterized by low management fees, enhancing their attractiveness relative to actively managed funds.
  • Importance of Critical Analysis:
    • Recognizes the potential biases in mutual fund performance claims.
    • Investors should thoroughly investigate fund prospectuses and performance metrics prior to investment decisions.