Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments

Abstract

People tend to hold overly favorable views of their abilities in many social and intellectual domains. The authors suggest that this overestimation occurs, in part, because people who are unskilled in these domains suffer a dual burden: Not only do these people reach erroneous conclusions and make unfortunate choices, but their incompetence robs them of the metacognitive ability to realize it. Across 4 studies, the authors found that participants scoring in the bottom quartile on tests of humor, grammar, and logic grossly overestimated their test performance and ability. Although their test scores put them in the 12th percentile, they estimated themselves to be in the 62nd. Several analyses linked this miscalibration to deficits in metacognitive skill, or the capacity to distinguish accuracy from error. Paradoxically, improving the skills of participants, and thus increasing their metacognitive competence, helped them recognize the limitations of their abilities.

Full text

Journal of Personality and Social Psychology
1999,
Vol. 77, No. 6. ] 121-1134Copyright 1999 by the American Psychological Association, Inc.
0022-3514/99/S3.00
Unskilled and Unaware of It: How Difficulties in Recognizing One's Own
Incompetence Lead to Inflated Self-Assessments
Justin Kruger and David Dunning
Cornell University
People tend to hold overly favorable views of their abilities in many social and intellectual domains. The
authors suggest that this overestimation occurs, in part, because people who are unskilled in these
domains suffer a dual burden: Not only do these people reach erroneous conclusions and make
unfortunate choices, but their incompetence robs them of the metacognitive ability to realize it. Across 4
studies, the authors found that participants scoring in the bottom quartile on tests of humor, grammar, and
logic grossly overestimated their test performance and ability. Although their test scores put them in the
12th percentile, they estimated themselves to be in the 62nd. Several analyses linked this miscalibration
to deficits in metacognitive skill, or the capacity to distinguish accuracy from error. Paradoxically,
improving the skills of participants, and thus increasing their metacognitive competence, helped them
recognize the limitations of their abilities.
It is one of the essential features of such incompetence that the person
so afflicted is incapable of knowing that he is incompetent. To have
such knowledge would already be to remedy a good portion of the
offense. (Miller, 1993, p. 4)
In 1995, McArthur Wheeler walked into two Pittsburgh banks
and robbed them in broad daylight, with no visible attempt at
disguise. He was arrested later that night, less than an hour after
videotapes of him taken .from surveillance cameras were broadcast
on the 11 o'clock news. When police later showed him the sur-
veillance tapes, Mr. Wheeler stared in incredulity. "But I wore the
juice," he mumbled. Apparently, Mr. Wheeler was under the
impression that rubbing one's face with lemon juice rendered it
invisible to videotape cameras (Fuocco, 1996).
We bring up the unfortunate affairs of Mr. Wheeler to make
three points. The first two are noncontroversial. First, in many
domains in life, success and satisfaction depend on knowledge,
wisdom, or savvy in knowing which rules to follow and which
strategies to pursue. This is true not only for committing crimes,
but also for many tasks in the social and intellectual domains, such
Justin Kruger and David Dunning, Department of Psychology, Cornell
University.
We thank Betsy Ostrov, Mark Stalnaker, and Boris Veysman for their
assistance in data collection. We also thank Andrew Hayes, Chip Heath,
Rich Gonzalez, Ken Savitsky, and David Sherman for their valuable
comments on an earlier version of this article, and Dov Cohen for alerting
us to the quote we used to begin this article. Portions of this research were
presented at the annual meeting of the Eastern Psychological Association,
Boston, March 1998. This research was supported financially by National
Institute of Mental Health Grant RO1 56072.
Correspondence concerning this article should be addressed to Justin
Kruger, who is now at the Department of Psychology, University of Illinois
at Urbana-Champaign, 603 East Daniel Street, Champaign, Illinois 61820,
or to David Dunning, Department of Psychology, Uris Hall, Cornell
University, Ithaca, New York 14853-7601. Electronic mail may be sent to
Justin Kruger at jkruger@s.psych.uiuc.edu or to David Dunning at
dad6@cornell.edu.
as promoting effective leadership, raising children, constructing a
solid logical argument, or designing a rigorous psychological
study. Second, people differ widely in the knowledge and strate-
gies they apply in these domains (Dunning, Meyerowitz, & Holz-
berg, 1989; Dunning, Perie, & Story, 1991; Story & Dunning,
1998),
with varying levels of success. Some of the knowledge and
theories that people apply to their actions are sound and meet with
favorable results. Others, like the lemon juice hypothesis of
McArthur Wheeler, are imperfect at best and wrong-headed, in-
competent, or dysfunctional at worst.
Perhaps more controversial is the third point, the one that is the
focus of this article. We argue that when people are incompetent in
the strategies they adopt to achieve success and satisfaction, they
suffer a dual burden: Not only do they reach erroneous conclusions
and make unfortunate choices, but their incompetence robs them of
the ability to realize it. Instead, like Mr. Wheeler, they are left with
the mistaken impression that they are doing just fine. As Miller
(1993) perceptively observed in the quote that opens this article,
and as Charles Darwin (1871) sagely noted over a century ago,
"ignorance more frequently begets confidence than does knowl-
edge"
(p. 3).
In essence, we argue that the skills that engender competence in
a particular domain are often the very same skills necessary to
evaluate competence in that domain—one's own or anyone else's.
Because of this, incompetent individuals lack what cognitive psy-
chologists variously term metacognition (Everson & Tobias,
1998),
metamemory (Klin, Guizman, & Levine, 1997), metacom-
prehension (Maki, Jonas, & Kallod, 1994), or self-monitoring
skills (Chi, Glaser, & Rees, 1982). These terms refer to the ability
to know how well one is performing, when one is likely to be
accurate in judgment, and when one is likely to be in error. For
example, consider the ability to write grammatical English. The
skills that enable one to construct a grammatical sentence are the
same skills necessary to recognize a grammatical sentence, and
thus are the same skills necessary to determine if a grammatical
mistake has been made. In short, the same knowledge that under-
lies the ability to produce correct judgment is also the knowledge
1121
This document is copyrighted by the American Psychological Association or one of its allied publishers.
This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.