The more people think they know about a topic in general, the more likely they are to emphasize knowledge with made-up information and false facts. A recent study terms this as over-claiming.
"Our work suggests that the seemingly straightforward task of judging one's knowledge may not be so simple, particularly for individuals who believe they have a relatively high level of knowledge to begin with," said first author Stav Atir, a psychological scientist at the Cornell University.
The researchers designed a series of experiments to test people's self-perceived knowledge, and compared it to their actual expertise.
In one set of experiments, 100 participants were asked to rate their general knowledge of personal finance, as well as their knowledge of 15 specific finance terms.
Most of the terms on the list were real (for example, Roth IRA, inflation, home equity), but the researchers also included three made-up terms (pre-rated stocks, fixed-rate deduction, annualized credit).
People who saw themselves as financial wizards were most likely to claim expertise of the bogus finance terms. "The same pattern emerged for other domains, including biology, literature, philosophy and geography," said Atir.
In another experiment, the researchers warned one set of 49 participants that some of the terms in a list would be made up.
The self-proclaimed experts were more likely to confidently claim familiarity with fake terms, such as "meta-toxins" and "bio-sexual" even after receiving the warning.
The research team warned that a tendency to over-claim, especially in self-perceived experts, may actually discourage individuals from educating themselves in precisely those areas in which they consider themselves knowledgeable -- leading to potentially disastrous outcomes.
A person could easily lead to uninformed decisions with devastating consequences if they fail to recognize or admit their knowledge gaps especially in the realm of finance or medicine.