Egocentric bias happens when you rely too heavily on your own perception than is true of reality.
The causes and motivations for egocentric bias were investigated in a 1983 journal entry by Brian Mullen of Murray State University. Inspired by the study by Ross et al. demonstrating the false consensus effect, Mullen's paper focused on the overestimation of consensus.
Mullen analyzed the NBC television show "Play the Percentages" to determine whether egocentric bias was rooted in a perceptual and unintentional distortion of reality versus a conscious, intentional motivation to appear normalized.
Subjects in this analysis were contestants from the show, 20–30 year old middle class married couple with equal gender distribution.
At the start of each show, studio audiences were asked several trivia questions, and the percentage of correct answers was recorded for later use in the game. During each round of the game, opposing contestants estimated the percentage of correct answers.
The contestant who had a closer estimate wins the percentage of correct answer as a score, and then if they answer said trivia question correctly, wins the remaining percentage for a maximum possible 100 points. The first couple to win 300 points received a cash prize, with the opportunity to win more prizes in bonus rounds. Thus, the show provided incentive for unbiased estimates of consensus.
Statistical analysis of the collected data showed that the "egocentric bias of false consensus was observed in spite of the potent incentive for unbiased estimates of consensus."
This analysis ultimately supports the hypothesis that egocentric bias is a result of unintentional perceptual distortion of reality rather than a conscious, intentional motivation to appear normalized.
From a psychological standpoint, memories appear to be stored in the brain in an egocentric manner: the role of oneself is magnified in one's experiences to make them more personally relevant and thereby easier to recall.
Early childhood memories, therefore, may be more difficult to recall since one's sense of self is less developed, so old memories do not connect as strongly to oneself as newer ones.
Moreover, egocentric bias may have evolved from hunter-gatherer times, in which communities were small and interdependent enough that individuals could assume that others around them had very similar outlooks. An egocentric view would have reduced cognitive load and increased communication efficiency.
In a 1993 study conducted in Japan, subjects were asked to write down fair or unfair behaviors that they themselves or others did. When writing about fair behavior, they tended to start with the word "I" rather than "others". Likewise, they began unfair behaviors with "others" rather than "I".
This demonstrates that people tend to attribute successes and positive behaviors to themselves, while placing the burden of failures and negative behaviors on others.
Furthermore, in this study there were gender differences detected; Japanese women, compared to men, remembered the behaviors of others more than their own, and were also more probable to characterize fair or unfair behavior to others compared to themselves.
Another study found that egocentric bias influences perceived fairness. Subjects felt that overpayment to themselves were more fair than overpayment to others; by contrast, they felt the underpayment to themselves were less fair than underpayment to others.
Greenberg's studies showed that this egocentrism was eliminated when the subjects were put in a self-aware state, which was applied in his study with a mirror being placed in front of the subjects.
When a person is not self-aware, they perceive that something can be fair to them but not necessarily fair to others. Therefore, fairness was something biased and subjective.
When a person is self-aware, there is a uniform standard of fairness and there is no bias. When made self-aware, subjects rated overpayment and underpayment to both themselves and to others as equally unfair.
It is believed that these results were obtained because self-awareness elevated subjects' concerns about perceived fairness in payment, thereby overriding egocentric tendencies.
The egocentric bias can also be clearly observed in young children, especially those who have not yet developed theory of mind, or the ability to understand concrete situations from the perspective of others.
In one study by Wimmer and Perner, a child and a stuffed animal were presented with two differently colored boxes and both are shown that one contains an object of interest. The experimenter then removed the stuffed animal from the room and moved the object into the other box.
When asked where the stuffed animal should search for the object, the children overwhelmingly tended to point to the box that they knew the object was in.
Rather than thinking about the animal's perspective, the children displayed an egocentric bias in assuming that the animal would share their point of view, even though the animal had no way of knowing the same information as them.
See Also: False-consensus effect, Self-serving bias, Bayesian probability