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Overconfidence effect

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The overconfidence effect is a well-established bias in which a person's subjective confidence in his or her judgements is reliably greater than the objective accuracy of those judgements, especially when confidence is relatively high. Overconfidence is one example of a miscalibration of subjective probabilities. Throughout the research literature, overconfidence has been defined in three distinct ways: (1) overestimation of one's actual performance; (2) overplacement of one's performance relative to others; and (3) overprecision in expressing unwarranted certainty in the accuracy of one's beliefs.

Table of contents:
  1. What is Overconfidence Bias?
  2. Overconfidence Bias in Finance and Investing
  3. Fear of Making a Mistake Can Help You Invest
  4. Types of Overconfidence
    1. Over Ranking
    2. Illusion of Control
    3. Timing Optimism
    4. Desirability Effect
  5. Examples
    1. Overestimation as a Type of Overconfidence
    2. Overplacement as a Type of Overconfidence
  6. Conclusion:

What is Overconfidence Bias?

The propensity to have a mistaken and inaccurate evaluation of our abilities, intellect, or ability is known as overconfidence bias. In a word, arrogance is the belief that we are superior to what we are. It's a harmful bias that's common in behavioral finance and the stock market. This session will go through the overconfidence bias in further detail. Learn more about behavioral finance in CFI's Behavioral Finance Course.

Overconfidence Bias in Finance and Investing

One of the most crucial talents in finance and investing is knowing where the markets are heading. Most market analysts feel their analytical abilities to be above average in their field. However, it is statistically impossible for most analysts to do better than the average analyst.

James Montier questioned 300 professional fund managers to find out if they believed their talents were above average. According to the survey, 74% of fund managers said yes. Seventy-four percent said they were better than average at investing. The remaining 26%, on the other hand, believed they were average. To put it another way, hardly anyone believed they were below average. These results, once again, reflect a statistical impossibility. The danger of having an overconfidence bias is that it increases your chances of making poor financial decisions. Overconfidence causes us to be less careful in our investing selections than we should be. A mistaken sense of knowledge and control is at the root of many of these blunders. Let's look at knowledge and control illusions, as well as how to prevent overconfidence bias.

Fear of Making a Mistake Can Help You Invest

While confidence is generally viewed as a positive in many situations, it is more commonly viewed as a weakness in investing. Successful investment necessitates careful risk management. However, being overconfident in our investing selections detracts from our capacity to manage risk effectively. Overconfidence bias causes us to see our financial selections as being less dangerous than they are.

Types of Overconfidence

Examining how overconfidence bias manifests in the actual world is the simplest method to understand the phenomenon completely. The most prevalent forms of biases are shown below.

Over Ranking

When someone overrates their performance, they are implying that it is better than it is. The truth is that most people consider themselves to be above average. This may be problematic in business and investment since it usually leads to taking on too much risk.

Illusion of Control

When people believe they have control over a situation when they don't, this is the illusion of control bias. People, on average, feel they have more control than they do. This may be extremely harmful in business or investment since it causes us to believe things are less risky than they are-failure to identify risk results in ineffective risk management appropriately.

Timing Optimism

Another facet of overconfidence psychology is optimism timing. People often overestimate their ability to work swiftly while underestimating how long it takes them to complete tasks. Businesspeople frequently underestimate how long a project will take to complete, especially for complex activities. Similarly, investors usually misjudge how long an investment will take to pay off.

Desirability Effect

When individuals overestimate the chances of something happening solely because the outcome is desired, this is known as the desirability effect. This is a sort of overconfidence bias that is frequently referred to as "wishful thinking." We make the error of assuming that a particular conclusion is more likely just because it is the one we want.


Overconfidence bias may cause issues for people because it prevents them from adequately preparing for a circumstance or causes them to enter a risky situation for which they are unprepared. To further grasp the notion, look at some instances of the three basic categories of overconfidence.

Overestimation as a Type of Overconfidence

Overconfidence is the notion that you are better at something than your actual talents or abilities suggest. A person with this kind of overconfidence exaggerates their abilities.

Overconfidence may be demonstrated by a person who believes their sense of direction is much superior to it is by embarking on a long trip without a map. If they become lost, they refuse to ask for directions.

Overconfident people believe they are much wiser than they are. The individual might demonstrate overconfidence by refusing to study for examinations, believing that they are so intelligent that they don't need to. As a result, individuals may obtain much worse grades than they would have otherwise.

A person who believes they have a photographic memory and a thorough comprehension of a subject may display arrogance by refusing to prepare for an exam, resulting in low performance on the test owing to lack of preparation. Someone who believes they are a terrific boxer and challenges an incredible fighter to a boxing contest exaggerates their ability. As a result of their overconfidence, the misinformed individual about their actual boxing ability might wind up being heavily defeated in the fight.

Because they are overconfident in their athletic talents, a person who has never swum before chooses to try out for the varsity swimming team without practicing. Their arrogance may keep them off the squad and make them the target of countless jokes from the other swimmers.

Overplacement as a Type of Overconfidence

The notion that you are superior to others is known as over placement. It entails comparing yourself to others in terms of talent or ability and assuming (often incorrectly) that you are better than most people at that skill or ability. Overplacement is a sort of overconfidence in which a student believes they are the brightest person in the class, or at least brighter than the majority of their peers. Even if they obtain lower marks, this individual believes they are smarter. Someone is so confident that they will be accepted to Harvard, which only takes the best students, that they apply. This shows that they feel they are superior to the majority of other students, even Harvard applicants. Overplacement may result in a student not being accepted to college at all.

This form of overconfidence is exhibited by those who have no qualifications and believe that you should listen to their thoughts regarding your health rather than those of your physician. Such people are usually adamant in their ideas and may even take offense if you don't follow their recommendations.

A person who believes they are indispensable to their company while, in reality, practically anybody could perform their job might exhibit overconfidence by being late to work because they believe they will never be fired. They may also be unreasonable in their demands for a raise, threatening to resign if they don't get their way. Someone who cannot sing but feels they can sing better than other people, on par with professional singers, may be overconfident enough to audition for American Idol and hope to win. When such a person uploads an audition tape, they may be laughed at or mocked, surprising to them.

Overprecision as a Type of Overconfidence

Overprecision is the belief that you, more than anyone else, know the truth or actuality of what will happen in the future. When someone has this form of overconfidence, they mistakenly assume they have some particular knowledge that gives them an advantage in predicting what will happen next.

In casino gaming, overprecision is fairly prevalent. As a result of their overconfidence in the form of overprecision, someone who is convinced they know what will come up next in a deck of cards or hit on a roulette wheel might face financial devastation.

Overprecision is a sort of overconfidence in which a person is overconfident about how a stock will perform and invests in exceptionally high-risk equities even though conventional wisdom would suggest against it. This form of overconfidence is displayed by someone who is not an election researcher but is sure that they know with certainty what the outcome of an election will be (without facts or statistical projections to back it up). Because of their overconfidence in the relationship's future trajectory, a person who believes their spouse or partner would never leave because their love is too strong may try to take advantage of the spouse or partner, driving the spouse away. Overconfidence is a type of overprecision in which a presidential contender believes they will win and does not campaign vigorously due to this belief. Their arrogance may lose them in the election.


These examples all depict circumstances in which people believe they are more capable or suited for a scenario than they are. While everyone might be overconfident at times, it is a personality feature for some people. The overconfidence effect occurs when a person consistently perceives themselves to be better or more informed than they are. It's necessary to have self-assurance, but a correct self-perception should accompany it. Expand your psychology knowledge now that you know what overconfidence is and have seen some examples. Extend your adventure by learning the definitions of some basic psychological words.

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