Bias

Bias is an inclination toward or against an individual, group, object, idea, or belief. It is often learned and commonly based on stereotypes about people because of their physical attributes or abilities or the groups to which they belong. As such, biases can be related to a person’s race, ethnicity, religion, gender, sexual orientation, socioeconomic status, or educational background.

Biases can be explicit or implicit. With explicit bias, people are conscious of their feelings and attitudes toward other people and things. They are aware that they are being biased, and their actions are done with intent. Making overtly racist comments to others or trash-talking an opposing team’s athletic skills are examples of explicit bias.

Implicit bias involves feelings and attitudes that are formed unconsciously. These biases often have their roots in childhood and are driven by familial, societal, or educational influences. With implicit bias, people are not generally aware of their biases, and their actions don’t have malevolent intent. A college professor failing to notice or call on a person of a particular ethnicity is an example of implicit bias.

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Because implicit biases are unconscious, they can be problematic when they influence things such as hiring practices, educational opportunities, medical assessments, and child-care policies. Several institutions have begun teaching strategies to overcome implicit bias. A nonprofit organization of social cognition researchers called Project Implicit developed a series of tests to measure people’s attitudes and beliefs in an effort to help individuals become aware of their implicit biases. Some research has shown that once people are aware of their implicit biases, they can be more motivated to prevent them from affecting their behaviors.

Categories and types of bias

Researchers have identified hundreds of types of bias. In addition to stereotype-based biases that lead to negative actions or discrimination against individuals and groups, there are contextual biases, statistical biases, and cognitive biases. Many biases fall under more than one category.

Contextual biases: These biases affect fields including, but not limited to, law enforcement, forensic science, academia, and journalism. They occur when irrelevant influences cause experts who may have good intentions to develop subconscious expectations, leading them to make erroneous decisions. Racial profiling—for example, when a police officer stops and searches a Hispanic man in a predominantly white area—is a contextual bias. A news report that features inflammatory comments from a politician without showing what led to the comments is another example.

Statistical biases: These biases are seen in experimental results and occur when there are flaws in the experiment design or the data collection process. If an experiment fails to survey a sufficiently broad population, it can yield results that are statistically biased. For example, a company survey asking people to rate a product may draw disproportionately from people who are highly pleased—or displeased—with the product, thereby underrepresenting the average respondent who may be less motivated to complete the survey.

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Cognitive biases: These widespread and varied forms of bias are the result of people allowing their perceptions of reality, as opposed to objective information, to color their thinking, leading to irrational conclusions or flawed decisions. There are more than 200 types of cognitive biases. Some of the more common cognitive biases include the following.

• Confirmation bias occurs when people seek out and focus on information that supports their existing ideas and beliefs and ignore information that doesn’t. For example, a person who believes vaccines have negative side effects may focus on stories about adverse reactions and ignore studies that find no connection between the two.
• The Dunning-Kruger effect occurs when people with limited knowledge or competence in a particular area overestimate their knowledge or abilities in relation to the performance of other people. For example, when asked, most people will say they are a better driver than the average person.
• Attribution bias occurs when people attribute motivations to the actions of others based on those individuals’ characteristics or abilities and without considering situational factors that may contribute to the actions. For example, a person might think someone who cut them off while driving is a terrible driver when the driver simply swerved to avoid debris in the road.
• The halo effect occurs when people let a positive first impression of someone shape their overall perception of the person based on one characteristic. An example of the halo effect, also sometimes called the “physical attractiveness stereotype,” is a person believing good-looking people are also kinder, smarter, and braver than less attractive people.
• Hindsight bias occurs when people see an event in hindsight as more predictable than it was and believe that they should have anticipated the outcome of the event prior to its happening. Examples can range from the relatively benign phenomenon of a Monday-morning quarterback questioning the actions of a football team to saying that the warning signs of the September 11 terrorist attacks were obvious and should not have been missed by intelligence organizations.
• Self-serving bias occurs when people attribute their successes to their own doing and attribute their failures to other people’s doing or circumstances beyond their control. An example would be a team that believed it won a game because of its superior skills and execution but lost another because of poor calls by the referees.