Ignorance of Ignorance: The Dunning-Kruger Effect

Psychologists David Dunning and Justin Kruger did a study in 1999 and published a paper in the Journal of Personality and Social Psychology titled "Unskilled and Unaware of It: How Difficulties in Recognizing One’s Own Incompetence Lead to Inflated Self-Assessments." Dunning has a Ph.D. in psychology from Stanford University, and Krugar has a Ph.D. in Social Psychology from Cornell.

Dunning and Kruger's research centered on the idea that people often overestimate their abilities. Across four studies, Dunning and Kruger found that those who tested in the bottom 12th percentile on tests of grammar, logic, and humor estimated themselves to be in the 62nd percentile. These studies also demonstrated that when the participants' skills were improved, they came to recognize their limitations.

Lack of knowledge is an essential feature of the Dunning-Kruger effect. Specifically, people who know little about a subject are likely to have strong opinions about that subject. These people are also less likely to listen to expert opinions, often insisting that they are fake or that the experts have ulterior motives, such as being paid to say untrue things.

Misinformation also plays a part in the Dunning-Kruger effect. People experiencing it believe the information that fits their opinion and typically do not bother with independent research. Not only are they unlikely to listen to experts, but they believe they know more than experts and instead support non-experts who share their opinions.

The concept of unknown unknowns is also central to the Dunning-Kruger effect. Unknown unknowns are information relevant to the topic at hand, but because people are so inexperienced with the topic, they don't realize that they lack this information. Likely, people experiencing the Dunning-Kruger effect do not understand their lack of abilities relating to a skill or topic because the lack of ability is an unknown unknown.

Dunning-Kruger also encompasses domain-specific beliefs. These stem from people believing they have accurate knowledge of a situation, but this knowledge is misguided. Examples of domain-specific misbeliefs include insisting that 25 percent of families in the U.S. receive welfare when the number is closer to 7 percent or believing that a ball rolled into a curved tube will exit the other end continuing to curve instead of traveling straight.

Reach-around knowledge is another factor that contributes to the Dunning-Kruger effect. Reach-around knowledge is information that may appear to be relevant to a situation but is, in reality, more general. Some examples: opinions about brand-name products that don't exist and strong feelings about a fictitious law.

The double curse of the Dunning-Kruger effect is the idea that people not only underperform, but they do not know enough to understand that they are underperforming. According to Dunning and Kruger's research, those who are the least skilled are most likely to overestimate themselves. This lack of self-awareness is a barrier to learning, and people with it are unlikely to grow.

Other studies have had insteresting results that demonstrate examples of the Dunning-Kruger effect. In one study, participants rated their knowledge of 150 varying topics. Among those were 30 topics made up by the experimenters. About 25 percent of respondents claimed knowledge of these invented topics. Another example of Dunning-Kruger is a home repair novice attempting to do electrical work despite not having any training or experience because they do not understand the risks of getting it wrong.

The Dunning Kruger effect is not without controversy. An essential part of the Dunning-Kruger effect is that the lowest performers are the most overconfident. Some researchers believe that most people are overconfident of their abilities, regardless of their true skill level. Some researchers also believe that highly skilled people are just as likely to be overconfident about their abilities as unskilled people.