The word bias comes from the 14th century term biais which means obliquity. The term still pertains to the quality of having some sort of slant or bend (OED, 1989). Bias, in an individual, can be latent due to the accumulation of experiences (Matsumoto, 2010, p. 423) but it can also be primed from a particular incident (Lange et al., 2010, p.331). It is often thought to be associated with heuristics and the mental short-cuts people take when making evaluations of a target (Kahneman, Tversky and Slovic, 1982).

Bias in the Real World

Bias can manifest itself in a myriad of different ways. It can present itself in statistical calculations, how news is reported, or even when making evaluative decisions about what is right and wrong. Many aspects within these issues are discussed below.

Cognitive Bias

One of the notable types of bias that often present itself to scholars is the cognitive bias. It pertains to the notion of using innate experiences to come to decisions that are ultimately intuitive in nature rather than taking the time to decipher through all relevant information (Kahneman & Shane, 2002, pp.51-52). It is one of the more popular types of bias to scholars simply because it lays the foundation for, and encompasses elements of, many other types of bias. The following are different manifestations of cognitive bias:
  • Confirmation bias: the tendency to notice only what supports your beliefs or hypotheses while discounting information that does not serve one’s own perspective (Shadish, 2007, p.48). It can potentially present itself both in everyday discussion and debate, as well as in the scholarly pursuits of researchers.
  • Correspondence bias (also known as actor-observer bias and fundamental attribution error): the tendency to attribute the (negatively valenced) outcome of an event to dispositional qualities inherent in the actor when one is observing and to attribute the same outcome to situational factors of the environment when one is the actor (Gilbert & Malone, 1995, p. 21).
  • Hindsight bias: a bias of the memory wherein people see something as predictable after it has already occurred. This type of bias has been found to be more prone to occur when individuals are in groups rather than alone (Choi & Choi, 2010, p.338).

Other Types of Bias

  • Media bias is another highly prevalent and discussed typology of bias. This bias is associated with the nature of how information and entertainment content disseminators pick and choose what they will circulate to the public (Baron, 2006, p.2). Often times the decisions of what to broadcast are influenced by contextual factors of an organization or person beyond merely what is needed by the consumer.
  • Publication bias -- the inclination of editors, reviewers and authors/ investigators to accept or submit work for publication on the basis of the strength or direction of the findings (Dickersin, 1990, p. 1385). This bias leads to the potential to over-represent particular findings in research and has encouraged regulation by many journals as well as the institution of federal laws to combat these effects (Tuma, 2010, p.290)
  • Experimental biasescan lead to misrepresentations in all types of research:
    • Selection bias- extraneous factors that influence who/what is included in a particular study (Trepepi et al., 2010 pp.c94-c95)
    • Information bias- systematic distortions when collecting data (Trepepi et al., 2010 pp.c94-c95)


Stereotypes, or categorical representations (Macrae & Bodenhausen, 2001, p.242), can be seen as a well learned set of associations that are automatically activated in the presence of a member (actual or symbolic equivalent) of a target group (Devine, 1989, p.6). Stereotypes are ingrained in experiences and often come to the forefront in a highly automatic and unconscious manner and can affect how people see the world (Macrae & Bodenhausen, 2001, p.245). In the aforementioned ways, as well as several others, bias is highly related to the idea and mechanisms inherent in stereotyping. Stereotypes are often negative and can be so prominent that nearly all members of a given society may be aware of them which implicitly could lead to large-scale gender or racial bias (Barnum & Perfetti, 2010, p.184). Unconscious cognitive activity is used to cognitively organize the social world and is manifested in individuals, like police officers, as a gut feeling that infers increased minority criminality (Barnum & Perfetti, 2010, p.201) or a racial bias.

Out-group homogeneity bias refers to the proclivity for members of a group to see each other as varied while seeing members of a different group as all the same. It is thought that because we have more information about our own group it is easier to differentiate them and harder to discern them in another group (Bordens & Horowitz, 2001, p.134). This particular bias, that has been observed in people, is thought to be a major contributing factor to why stereotypes occur and why they persist.

Potential Facilitators of Bias

There is no single mechanism that is agreed upon as the cause of bias in people but there are several mechanisms that researchers believe may come together to produce and maintain it. The use of heuristics and mental shortcuts are largely thought to be what precipitates bias by engaging the most representative versions and attributes of how one sees a target (Kahneman, Tversky and Slovic, 1982). Nevertheless it is still important to understand why people rely on these representations. Although there could be a multitude of ways to explain how this reliance comes to be the following two explanations will be examined:
  • Cognitive dissonance theory -- ideas that are oppositional to one’s inherent beliefs cause feelings of anxiety. To avoid these anxious feelings people avoid counter-attitudinal information or discount it when see it (Festinger, 1957). Along the lines of this theory, when heuristics are automatically activated people may be inclined to avoid information that contradicts this “intuition” and become biased toward the initial decision.

  • Dual process theory has two systems for mental processing that work separately as well as in concert at times. The first system is automatic and deals with innate pattern recognition while the second system is deliberative and logical (Kadar, 2010, p126). Information is thought, under this theory, to pass from system 1 to system 2. System 2 is believed to only give perfunctory attention unless the task is novel or difficult and does not work as well under limitations (i.e. cognitive load or memory issues). Within this theory, when people encounter tasks that are not novel they go with their automatic decision which is based on superficial pattern recognition and is biased away from deliberate and logical thinking. The more novel an experience is the less chance it is thought to be susceptible to one’s own biases.

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Bias. (1989). in Oxford English Dictionary (2nd ed.).

Baron, D. (2006). Persistent media bias. Journal of Public Economics, 90, 1-36.

Barnum, C., & Perfett, R. (2010). Race-sensitive choices by police officers in traffic stop encounters, Police Quarterly, 13(2), 180-208.

Bordens, K., & Horowitz, I. (2001). Social psychology. London: Psychology press, 13-14.

Choi, D., & Choi, I. (2010). Groups and individuals: The Moderating role of plausibility. Journal of Applied Psychology, 40 (2), 325-342.

Devine, P. (1989). Stereotypes and prejudice: Their automatic and controlled components. Journal of Personality and Social Psychology, 56 (1), 5-18.

Dickerson, J. (1990). The Existence of publication bias and risk factors for its occurrence. Journal of the American Medical Association, 263 (10), 1385-1389.

Festinger, L. (1957). A theory of cognitive dissonance. Stanford, CA: Stanford University Press.

Gilbert, D., & Malone, P. (1995). The Correspondence bias. Psychological Bulletin, 200 (1), 21-38.

Kadar, N. (2010). Systemic bias in peer review: Suggested causes and potential remedies. Journal of Laparoendoscopic & Advanced Surgical Techniques, 20 (2), 123-128.

Kahneman, Daniel; Shane, Frederick (2002). "Representativeness revisited: Attribute substitution in intuitive judgment". in Thomas Gilovich, Dale Griffin, Daniel Kahneman.

Heuristics and Biases: The Psychology of Intuitive Judgment. Cambridge: Cambridge University Press. pp. 51–52.

Kahneman, D., Tversky, A. & Slovic, P., eds. (1982) Judgment under uncertainty: Heuristics & biases. Cambridge, UK: Cambridge University Press.

Kanazawa, S., & Kovar, J. (2004). Why beautiful people are more intelligent. Intelligence, 32, 227-243.

Lange, W., Salemink, E., Windey, I., Keijsers, G., Krans, J., Becker, E., & Rinck, M. Does modified interpretation bias influence automatic avoidance behaviour? Applied Cognitive Psychology, 24 (3).

Macrae, C., & Bodenhausen, G. (2001). Social cognition: Categorical person perception. British Journal of Psychology, 92 (1), 242.

Matsumoto, E. (2010). Bias in attending to emotional facial expressions: Anxiety and visual search efficiency. Applied Cognitive Psychology, 24 (3), 414-424.

Rhode, D. (2010). The Beauty bias: The Injustice of appearance in life and life. Oxford: Oxford University Press.

Rosen, L., & Underwood, M. (2010). Facial attractiveness as a moderator of the association between social and physical aggression and popularity in adolescents. Journal of School Psychology, 48, 313-333.

Shadish, W. (2007). Critical thinking in quasi-experimentation. in R. J. Sternberg, H. J. Roediger, and D. F. Halpern (Eds.), Critical Thinking in psychology (37-53). Cambridge, UK: Cambridge University Press.