Illusory superiority has been found in individuals' comparisons of themselves with others in a variety of aspects of life, including performance in academic circumstances (such as class performance, exams and overall intelligence), in working environments (for example in
job performance), and in social settings (for example in estimating one's
popularity, or the extent to which one possesses desirable personality traits, such as
honesty or
confidence), and in everyday abilities requiring particular skill. This interpretation is confirmed by
experiments which varied the amount of interpretive freedom. As subjects evaluated themselves on a specific, well-defined attribute, illusory superiority remains.
Academic ability, job performance, lawsuits going to trial, and stock trading In a survey of faculty at the
University of Nebraska–Lincoln, 68% rated themselves in the top 25% for teaching ability, and 94% rated themselves as above average. In a similar survey, 87% of
Master of Business Administration students at
Stanford University rated their academic performance as above the median. Another study showed that employees routinely overstate their level of professional knowledge by 20% compared to that of their coworkers. Illusory superiority has also explained phenomena such as the large amount of
stock market trading (as each
trader thinks they are the best, and most likely to succeed), and the number of lawsuits that go to trial (because, due to illusory superiority, many lawyers have an inflated belief that they will win a case).
Cognitive tasks In Kruger and Dunning's experiments, participants were given specific tasks (such as solving
logic problems, analyzing
grammar questions, and determining whether jokes were funny), and were asked to evaluate their performance on these tasks relative to the rest of the group, enabling a direct comparison of their actual and perceived performance. The paper, titled "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments", won an
Ig Nobel Prize in 2000. In 2003, Dunning and Joyce Ehrlinger, also of
Cornell University, published a study that detailed a shift in people's views of themselves influenced by external cues. Cornell undergraduates were given tests of their knowledge of geography, some intended to positively affect their self-views, others intended to affect them negatively. They were then asked to rate their performance, and those given the positive tests reported significantly better performance than those given the negative. Daniel Ames and Lara Kammrath extended this work to sensitivity to others, and the subjects' perception of how sensitive they were. Research by Burson, Larrick, and Klayman suggests that the effect is not so obvious and may be due to
noise and bias levels. Dunning, Kruger, and coauthors' 2008 paper on this subject comes to qualitatively similar conclusions after making some attempt to test alternative explanations.
Driving ability Svenson (1981) surveyed 161 students in
Sweden and the
United States, asking them to compare their
driving skills and
safety to other people's. For driving skills, 93% of the U.S. sample and 69% of the Swedish sample put themselves in the top 50%; for safety, 88% of the U.S. and 77% of the Swedish put themselves in the top 50%. McCormick, Walkey and Green (1986) found similar results in their study, asking 178 participants to evaluate their position on eight different dimensions of driving skills (examples include the "dangerous–safe" dimension and the "considerate–inconsiderate" dimension). Only a small minority rated themselves as below the median, and when all eight dimensions were considered together it was found that almost 80% of participants had evaluated themselves as being an above-average driver. One commercial survey showed that 36% of drivers believed they were an above-average
driver while texting or sending emails compared to other drivers; 44% considered themselves average, and 18% below average.
Health Illusory superiority was found in a
self-report study of
health behaviors (Hoorens & Harris, 1998) that asked participants to estimate how often they and their peers carried out healthy and unhealthy behaviors. Participants reported that they carried out healthy behaviors more often than the average peer, and unhealthy behaviors less often. The findings held even for expected future behavior.
Immunity to bias Subjects describe themselves in positive terms compared to other people, and this includes describing themselves as less susceptible to bias than other people. This effect is called the "
bias blind spot" and has been demonstrated independently.
IQ Illusory superiority that applies to
IQ is known as the "Downing effect". This describes the tendency of people with a below-average IQ to overestimate their IQ, and of people with an above-average IQ to underestimate their IQ (similar trend to the
Dunning-Kruger effect). This tendency was first observed by C. L. Downing, who conducted the first
cross-cultural studies on perceived intelligence. His studies also showed that the ability to accurately estimate other people's IQs was proportional to one's own IQ (i.e., the lower the IQ, the less capable of accurately appraising other people's IQs). People with high IQs are better overall at appraising other people's IQs, but when asked about the IQs of people with similar IQs as themselves, they are likely to rate them as having higher IQs. The disparity between actual IQ and perceived IQ has also been noted between genders by British psychologist
Adrian Furnham, in whose work there was a suggestion that, on average, men are more likely to overestimate their intelligence by 5 points, while women are more likely to underestimate their IQ by a similar margin.
Memory Illusory superiority has been found in studies comparing
memory self-reports, such as Schmidt, Berg & Deelman's research in older adults. This study involved participants aged between 46 and 89 years of age comparing their own memory to that of peers of the same age group, 25-year-olds and their own memory at age 25. This research showed that participants exhibited illusory superiority when comparing themselves to both peers and younger adults, however the researchers asserted that these judgments were only slightly related to age.
Popularity In Zuckerman and Jost's study, participants were given detailed questionnaires about their
friendships and asked to assess their own
popularity. Using
social network analysis, they were able to show that participants generally had exaggerated perceptions of their own popularity, especially in comparison to their own friends. Despite the fact that most people in the study believed that they had more friends than their friends, a 1991 study by sociologist Scott L. Feld on the
friendship paradox shows that on average, due to
sampling bias, most people have fewer friends than their friends have.
Relationship happiness Researchers have also found illusory superiority in relationship satisfaction. For example, one study found that participants perceived their own relationships as better than others' relationships on average, but thought that the majority of people were happy with their relationships. It also found evidence that the higher the participants rated their own relationship happiness, the more superior they believed their relationship was—illusory superiority also increased their own relationship satisfaction. This effect was pronounced in men, whose satisfaction was especially related to the perception that one's own relationship was superior as well as to the assumption that few others were unhappy in their relationships. On the other hand, women's satisfaction was particularly related to the assumption that most people were happy with their relationship.
Self, friends, and peers One of the first studies that found illusory superiority was carried out in the
United States by the
College Board in 1976. Research by Perloff and Fetzer, and
Henri Tajfel and
John C. Turner also found friends being rated higher than other peers. Tajfel and Turner attributed this to an "
ingroup bias" and suggested that this was motivated by the individual's desire for a "
positive social identity". == Moderating factors ==