What Is a Confirmation Bias?

We interpret facts to confirm our beliefs

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Where do your beliefs and opinions come from? If you are like most people, you probably like to think that your beliefs are the result of years of experience and objective analysis of the information you have available. The reality is that all of us are susceptible to a tricky problem known as a confirmation bias.

While we like to imagine that our beliefs are rational, logical, and objective, the fact is that our ideas are often based on paying attention to the information that upholds our ideas.

At the same time, we tend to ignore the information that challenges our existing beliefs.

Understanding Confirmation Bias

A confirmation bias is a type of cognitive bias that involves favoring information which confirms previously existing beliefs or biases.

For example, imagine that a person holds a belief that left-handed people are more creative than right-handed people. Whenever this person encounters a person that is both left-handed and creative, they place greater importance on this "evidence" that supports what they already believe. This individual might even seek "proof" that further backs up this belief while discounting examples that do not support the idea.

Confirmation biases impact how people gather information, but they also influence how we interpret and recall information. For example, people who support or oppose a particular issue will not only seek information to support it, they will also interpret news stories in a way that upholds their existing ideas.

They will also remember things in a way that reinforces these attitudes.

Confirmation Biases in Action

Consider the debate over gun control. Sally, for example, is in support of gun control. She seeks out news stories and opinion pieces that reaffirm the need for limitations on gun ownership. When she hears stories about shootings in the media, she interprets them in a way that supports her existing beliefs.

Henry, on the other hand, is adamantly opposed to gun control. He seeks out news sources that are aligned with his position. When he comes across news stories about shootings, he interprets them in a way that supports his current point of view.

These two people have very different opinions on the same subject and their interpretations are based on that. Even if they read the same story, their bias tends to shape the way they perceive it because it confirms their beliefs.

The Impact of Confirmation Biases

In the 1960s, cognitive psychologist Peter Cathcart Wason conducted a number of experiments known as Wason's rule discovery task. He demonstrated that people have a tendency to seek information that confirms their existing beliefs. Unfortunately, this type of bias can prevent us from looking at situations objectively. It can also influence the decisions we make and can lead to poor or faulty choices.

During an election season, for example, people tend to seek positive information that paints their favored candidates in a good light. They will also look for information that casts the opposing candidate in a negative light.

By not seeking out objective facts, interpreting information in a way that only supports their existing beliefs, and only remembering details that uphold these beliefs, they often miss important information.

These details and facts might have otherwise influenced their decision on which candidate to support.

Observations by Psychologists

In his book, "Research in Psychology: Methods and Design," C. James Goodwin gives a great example of confirmation bias as it applies to extrasensory perception.

"Persons believing in extrasensory perception (ESP) will keep close track of instances when they were 'thinking about Mom, and then the phone rang and it was her!' Yet they ignore the far more numerous times when (a) they were thinking about Mom and she didn't call and (b) they weren't thinking about Mom and she did call. They also fail to recognize that if they talk to Mom about every two weeks, their frequency of "thinking about Mom" will increase near the end of the two-week-interval, thereby increasing the frequency of a 'hit.'"

As Catherine A. Sanderson points out in her book, "Social Psychology," confirmation bias also helps form and re-confirm stereotypes we have about people.

"We also ignore information that disputes our expectations. We are more likely to remember (and repeat) stereotype-consistent information and to forget or ignore stereotype-inconsistent information, which is one-way stereotypes are maintained even in the face of disconfirming evidence. If you learn that your new Canadian friend hates hockey, loves sailing and that your new Mexican friend hates spicy foods and loves rap music, you are less likely to remember this new stereotype-inconsistent information."

Confirmation bias is not only found in our personal beliefs, it can affect our professional endeavors as well. In the book, "Psychology," Peter O. Gray offers this example of how it may affect a doctor's diagnosis.

"Groopman (2007) points out that the confirmation bias can couple with the availability bias in producing misdiagnosis in a doctor's office. A doctor who had jumped to a particular hypothesis as to what disease a patient has may then ask questions and look for evidence that tends to confirm that diagnosis while overlooking evidence that would tend to disconfirm it. Groopman suggests that medical training should include a course in inductive reasoning that would make new doctors aware of such biases. Awareness, he things, would lead to fewer diagnostic errors. A good diagnostician will test his or her initial hypothesis by searching for evidence against that hypothesis."

A Word From Verywell

Unfortunately, we all have confirmation bias. Even if you believe you are very open-minded and only observe the facts before coming to conclusions, it's very likely that some bias will shape your opinion in the end. It is difficult to combat this natural tendency.

Yet, if we know about confirmation bias and accept the fact that it does exist, we can make attempts to recognize it. That may help us see things from another perspective, though it's never a guarantee.

Sources:

Gray PO. Psychology. 6th ed. New York: Worth Publishers; 2011.

Goodwin CJ, Goodwin KA. Research in Psychology: Methods and Design. 7th ed. New Jersey: John Wiley and Sons; 2013.

Poletiek FH. Hypothesis-Testing Behavior. Psychology Press; 2013.

Sanderson CA. Social Psychology. 1st ed. New Jersey: John Wiley and Sons; 2010.

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