Psychology · Self-evaluation

Lake Wobegon Effect

Reference entry · last updated October 3, 2026

The Lake Wobegon effect is the tendency to judge oneself more favorably than peers. In comparative self-evaluation, it is commonly called the better-than-average effect. When the perceived advantage exceeds actual rank, it constitutes overplacement.[1]

First principles and definitions

A comparative judgment needs a defined attribute and comparison group. A claim of superior driving skill, for example, concerns a person's position among specified drivers. Bias requires a mismatch between that judgment and the relevant benchmark.[1]

The mean is the sum of values divided by their count. The median divides an ordered distribution at its midpoint. A majority can exceed the mean in a skewed distribution. At most half of a group can be strictly above its median on one shared measure.[1]

For example, the scores 0, 8, 9, 10, and 11 have a mean of 7.6 and a median of 9. Four scores exceed the mean; two exceed the median. This is an illustrative arithmetic example.

Moore and Healy distinguish three forms of overconfidence:[1]

Name and broader usage

The name refers to Garrison Keillor's fictional town in A Prairie Home Companion, where “all the children are above average.” Moran and Morgan also use the term for inflated recommendations in recruitment. That usage concerns favorable judgments of candidates, extending beyond self-ratings.[2]

Driving research

In 1981, Ola Svenson reported a study of licensed student drivers in the United States and Sweden. Participants estimated their driving skill or safety relative to other participants in their experimental group. Most placed themselves above the median on both measures.[3]

The study measured self-ratings, without testing participants' driving performance. Its result documents a pattern in comparative judgments within these student samples; it does not establish the accuracy of any particular driver's self-assessment or the prevalence among all drivers.[3]

Explanations and limits

Moore and Healy propose that unequal information about self and others can produce overplacement. Their model predicts that weaker information about others pulls estimates of others closer to prior expectations. On easy tasks, this can make others seem less successful than oneself; on hard tasks, it can produce the reverse.[1]

Question wording also matters. Kim, Kwon, and Chiu found that participants could interpret an “average” person as below the median in abilities perceived as easy. A better-than-average response may therefore depend on what the respondent understands ‘average’ to mean. The authors present this cognitive account as a complement to self-enhancement explanations.[4]

Interpreting a self-assessment

Interpreting a superiority claim requires specifying the comparison group, criterion, and meaning of “average.” An actual rank provides a benchmark for overplacement. Absolute performance and certainty require separate checks.[1][4]

See also

References

  1. Don A. Moore and Paul J. Healy, “The Trouble With Overconfidence,” Psychological Review 115(2), 502–517 (2008). DOI: 10.1037/0033-295X.115.2.502. Free full text at the co-author's university site (PDF).
  2. John Moran and John Morgan, “Employee Recruiting and the Lake Wobegon Effect,” working paper, June 2001, p. 2. Author-hosted full text (PDF).
  3. Ola Svenson, “Are We All Less Risky and More Skillful than Our Fellow Drivers?” Acta Psychologica 47, 143–148 (1981). Full-text scan hosted by Gwern (PDF).
  4. Young-Hoon Kim, Heewon Kwon, and Chi-Yue Chiu, “The Better-Than-Average Effect Is Observed Because ‘Average’ Is Often Construed as Below-Median Ability,” Frontiers in Psychology 8, 898 (2017). DOI: 10.3389/fpsyg.2017.00898. PubMed record and author abstract.