Table of ContentsView AllTable of ContentsThe Confirmation BiasThe Hindsight BiasThe Anchoring BiasThe Misinformation EffectThe Actor-Observer BiasThe False Consensus EffectThe Halo EffectThe Self-Serving BiasThe Availability HeuristicThe Optimism BiasOther Kinds
Table of ContentsView All
View All
Table of Contents
The Confirmation Bias
The Hindsight Bias
The Anchoring Bias
The Misinformation Effect
The Actor-Observer Bias
The False Consensus Effect
The Halo Effect
The Self-Serving Bias
The Availability Heuristic
The Optimism Bias
Other Kinds
Close
Although we like to believe that we’re rational and logical, the fact is that we are continually under the influence ofcognitive biases. These biasesdistort thinking, influence beliefs, and sway the decisions and judgments that people make each and every day.
Sometimes, cognitive biases are fairly obvious. You might even find that you recognize these tendencies in yourself or others. In other cases, these biases are so subtle that they are almost impossible to notice.
At a GlanceAttention is a limited resource. This means we can’t possibly evaluate every possible detail and event when forming thoughts and opinions. Because of this, we often rely onmental shortcutsthat speed up our ability to make judgments, but this can sometimes lead to bias. There are many types of biases—including the confirmation bias, the hindsight bias, and the anchoring bias, just to name a few—that can influence our beliefs and actions daily.
At a Glance
Attention is a limited resource. This means we can’t possibly evaluate every possible detail and event when forming thoughts and opinions. Because of this, we often rely onmental shortcutsthat speed up our ability to make judgments, but this can sometimes lead to bias. There are many types of biases—including the confirmation bias, the hindsight bias, and the anchoring bias, just to name a few—that can influence our beliefs and actions daily.
The following are just a few types of cognitive biases that have a powerful influence on how you think, how you feel, and how you behave.
Tara Moore / Getty Images
Theconfirmation biasis the tendency to listen more often to information that confirms our existing beliefs. Through this bias, people tend to favor information that reinforces the things they already think or believe.
Examples include:
People on two sides of an issue can listen to the same story and walk away with different interpretations that they feel validates their existing point of view. This is often indicative that the confirmation bias is working to “bias” their opinions.
The problem with this is that it can lead to poor choices, an inability to listen to opposing views, or even contribute tootheringpeople who hold different opinions.
Things that we can do to help reduce the impact of confirmation bias include being open to hearing others' opinions and specifically looking for/researching opposing views, reading full articles (and not just headlines), questioning the source, and [doing] the research yourself to see if it is a reliable source.—RACHEL GOLDMAN, PHD, FTOS
Things that we can do to help reduce the impact of confirmation bias include being open to hearing others' opinions and specifically looking for/researching opposing views, reading full articles (and not just headlines), questioning the source, and [doing] the research yourself to see if it is a reliable source.
—RACHEL GOLDMAN, PHD, FTOS
Thehindsight biasis a common cognitive bias that involves the tendency to see events, even random ones, as more predictable than they are. It’s also commonly referred to as the “I knew it all along” phenomenon.
Some examples of the hindsight bias include:
Classic ResearchIn one classic psychology experiment, college students were asked to predict whether they thought then-nominee Clarence Thomas would be confirmed to the U.S. Supreme Court.Prior to the Senate vote, 58% of the students thought Thomas would be confirmed. The students were polled again following Thomas’s confirmation, and a whopping 78% of students said they had believed Thomas would be confirmed.
Classic Research
In one classic psychology experiment, college students were asked to predict whether they thought then-nominee Clarence Thomas would be confirmed to the U.S. Supreme Court.Prior to the Senate vote, 58% of the students thought Thomas would be confirmed. The students were polled again following Thomas’s confirmation, and a whopping 78% of students said they had believed Thomas would be confirmed.
In one classic psychology experiment, college students were asked to predict whether they thought then-nominee Clarence Thomas would be confirmed to the U.S. Supreme Court.
Prior to the Senate vote, 58% of the students thought Thomas would be confirmed. The students were polled again following Thomas’s confirmation, and a whopping 78% of students said they had believed Thomas would be confirmed.
The hindsight bias occurs for a combination of reasons, including our ability to “misremember” previous predictions, our tendency to view events as inevitable, and our tendency to believe we could have foreseen certain events.
The effect of this bias is that it causes us tooverestimate our abilityto predict events. This can sometimes lead people to take unwise risks.
While the existence of the anchoring bias is well documented, its causes are still not fully understood. Some research suggests that the source of the anchor information may play a role. Other factors such as priming and mood also appear to have an influence.
Like other cognitive biases, anchoring can have an effect on the decisions you make each day. For instance, it can influence how much you are willing to pay for your home. However, it can sometimes lead to poor choices and make it more difficult for people to consider other factors that might also be important.
For example:
Classic Memory Research
When the witnesses were then questioned a week later whether they had seen any broken glass, those who had been asked the “smashed into” version of the question were more likely to report incorrectly that they had seen broken glass.
There are a few factors that may play a role in this phenomenon. New information may get blended with older memories. In other cases, new information may be used to fill in “gaps” in memory.
The effects of misinformation can range from the trivial to much more serious. It might cause you to misremember something you thought happened at work, or it might lead to someone incorrectly identifying the wrong suspect in a criminal case.
The Mandela Effect: How Masses of People Can Have the Same False Memory
When it comes to our own actions, we are often far too likely to attribute things to external influences. For example:
When it comes to explaining other people’s actions, however, we are far more likely to attribute their behaviors to internal causes. For example:
While there are many factors that may play a role, perspective plays a key role. When we are the actors in a situation, we are able to observe our own thoughts and behaviors. When it comes to other people, however, we cannot see what they are thinking. This means we focus on situational forces for ourselves, but guess at the internal characteristics that cause other people’s actions.
The problem with this is that it often leads to misunderstandings. Each side of a situation is essentially blaming the other side rather than thinking about all of the variables that might be playing a role.
Thefalse consensus effectis the tendency people have to overestimate how much other people agree with their own beliefs, behaviors, attitudes, and values. For example:
Researchers believe that the false consensus effect happens for a variety of reasons. First, the people we spend the most time with, our family and friends, do often tend to share very similar opinions and beliefs. Because of this, we start to think that this way of thinking is the majority opinion even when we are with people who are not among our group of family and friends.
Another key reason this cognitive bias trips us up so easily is that believing that other people are just like us is good for ourself-esteem. It allows us to feel “normal” and maintain a positive view of ourselves in relation to other people.
This can lead people not only to incorrectly think that everyone else agrees with them—it can sometimes lead them to overvalue their own opinions. It also means that we sometimes don’t consider how other people might feel when making choices.
One factor that may influence the halo effect is our tendency to want to be correct. If our initial impression of someone was positive, we want to look for proof that our assessment was accurate. It also helps people avoid experiencingcognitive dissonance, which involves holding contradictory beliefs.
This cognitive bias can have a powerful impact in the real world. For example, job applicants perceived as attractive and likable are also more likely to be viewed as competent, smart, and qualified for the job.
Theself-serving biasis a tendency for people tend to give themselves credit for successes but lay the blame for failures on outside causes. When you do well on a project, you probably assume that it’s because you worked hard. But when things turn out badly, you are more likely to blame it on circumstances or bad luck.
Some examples of this:
This bias does serve an important role in protecting self-esteem. However, it can often also lead to faulty attributions such as blaming others for our own shortcomings.
Theavailability heuristicis the tendency to estimate the probability of something happening based on how many examples readily come to mind. Some examples of this:
It is essentially a mental shortcut designed to save us time when we are trying to determine risk. The problem with relying on this way of thinking is that it often leads to poor estimates and bad decisions.
Smokers who have never known someone to die of a smoking-related illness, for example, might underestimate the health risks of smoking. In contrast, if you have two sisters and five neighbors who have had breast cancer, you might believe it is even more common than statistics suggest.
Theoptimism biasis a tendency to overestimate the likelihood that good things will happen to us while underestimating the probability that negative events will impact our lives. Essentially, we tend to be too optimistic for our own good.
For example, we may assume that negative events won’t affect us such as:
This bias can lead people to take health risks like smoking, eating poorly, or not wearing a seat belt. The bad news is that research has found that this optimism bias is incredibly difficult to reduce.
There is good news, however. This tendency toward optimism helps create a sense of anticipation for the future, giving people the hope and motivation they need to pursue their goals.
Other Kinds of Cognitive Bias
Many other cognitive biases can distort how we perceive the world. Just a partial list:
Keep in Mind
The cognitive biases above are common, but this is only a sampling of the many biases that can affect your thinking. These biases collectively influence much of our thoughts and ultimately, decision making.
Many of these biases are inevitable. We simply don’t have the time to evaluate every thought in every decision for the presence of any bias. Understanding these biases is very helpful in learning how they can lead us to poor decisions in life.
8 SourcesVerywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Dietrich D, Olson M.A demonstration of hindsight bias using the Thomas confirmation vote.Psychol Rep. 1993;72(2):377-378. doi:/10.2466/pr0.1993.72.2.377Lee KK.An indirect debiasing method: Priming a target attribute reduces judgmental biases in likelihood estimations.PLoS ONE. 2019;14(3):e0212609. doi:10.1371/journal.pone.0212609Saposnik G, Redelmeier D, Ruff CC, Tobler PN.Cognitive biases associated with medical decisions: A systematic review.BMC Med Inform Decis Mak. 2016;16(1):138. doi:10.1186/s12911-016-0377-1Furnham A., Boo HC.A literature review of anchoring bias.The Journal of Socio-Economics.2011;40(1):35-42. doi:10.1016/j.socec.2010.10.008Loftus EF.Leading questions and the eyewitness report.Cognitive Psychology. 1975;7(4):560-572. doi:10.1016/0010-0285(75)90023-7Challies DM, Hunt M, Garry M, Harper DN.Whatever gave you that idea? False memories following equivalence training: a behavioral account of the misinformation effect.J Exp Anal Behav. 2011;96(3):343-362. doi:10.1901/jeab.2011.96-343Miyamoto R, Kikuchi Y.Gender differences of brain activity in the conflicts based on implicit self-esteem.PLoS ONE. 2012;7(5):e37901. doi:10.1371/journal.pone.0037901Weinstein ND, Klein WM.Resistance of personal risk perceptions to debiasing interventions.Health Psychol. 1995;14(2):132–140. doi:10.1037//0278-6133.14.2.132Additional ReadingGratton G, Cooper P, Fabiani M, Carter CS, Karayanidis F.Dynamics of cognitive control: theoretical bases, paradigms, and a view for the future.Psychophysiology. 2018;55(3). doi:10.1111/psyp.13016
8 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Dietrich D, Olson M.A demonstration of hindsight bias using the Thomas confirmation vote.Psychol Rep. 1993;72(2):377-378. doi:/10.2466/pr0.1993.72.2.377Lee KK.An indirect debiasing method: Priming a target attribute reduces judgmental biases in likelihood estimations.PLoS ONE. 2019;14(3):e0212609. doi:10.1371/journal.pone.0212609Saposnik G, Redelmeier D, Ruff CC, Tobler PN.Cognitive biases associated with medical decisions: A systematic review.BMC Med Inform Decis Mak. 2016;16(1):138. doi:10.1186/s12911-016-0377-1Furnham A., Boo HC.A literature review of anchoring bias.The Journal of Socio-Economics.2011;40(1):35-42. doi:10.1016/j.socec.2010.10.008Loftus EF.Leading questions and the eyewitness report.Cognitive Psychology. 1975;7(4):560-572. doi:10.1016/0010-0285(75)90023-7Challies DM, Hunt M, Garry M, Harper DN.Whatever gave you that idea? False memories following equivalence training: a behavioral account of the misinformation effect.J Exp Anal Behav. 2011;96(3):343-362. doi:10.1901/jeab.2011.96-343Miyamoto R, Kikuchi Y.Gender differences of brain activity in the conflicts based on implicit self-esteem.PLoS ONE. 2012;7(5):e37901. doi:10.1371/journal.pone.0037901Weinstein ND, Klein WM.Resistance of personal risk perceptions to debiasing interventions.Health Psychol. 1995;14(2):132–140. doi:10.1037//0278-6133.14.2.132Additional ReadingGratton G, Cooper P, Fabiani M, Carter CS, Karayanidis F.Dynamics of cognitive control: theoretical bases, paradigms, and a view for the future.Psychophysiology. 2018;55(3). doi:10.1111/psyp.13016
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Dietrich D, Olson M.A demonstration of hindsight bias using the Thomas confirmation vote.Psychol Rep. 1993;72(2):377-378. doi:/10.2466/pr0.1993.72.2.377Lee KK.An indirect debiasing method: Priming a target attribute reduces judgmental biases in likelihood estimations.PLoS ONE. 2019;14(3):e0212609. doi:10.1371/journal.pone.0212609Saposnik G, Redelmeier D, Ruff CC, Tobler PN.Cognitive biases associated with medical decisions: A systematic review.BMC Med Inform Decis Mak. 2016;16(1):138. doi:10.1186/s12911-016-0377-1Furnham A., Boo HC.A literature review of anchoring bias.The Journal of Socio-Economics.2011;40(1):35-42. doi:10.1016/j.socec.2010.10.008Loftus EF.Leading questions and the eyewitness report.Cognitive Psychology. 1975;7(4):560-572. doi:10.1016/0010-0285(75)90023-7Challies DM, Hunt M, Garry M, Harper DN.Whatever gave you that idea? False memories following equivalence training: a behavioral account of the misinformation effect.J Exp Anal Behav. 2011;96(3):343-362. doi:10.1901/jeab.2011.96-343Miyamoto R, Kikuchi Y.Gender differences of brain activity in the conflicts based on implicit self-esteem.PLoS ONE. 2012;7(5):e37901. doi:10.1371/journal.pone.0037901Weinstein ND, Klein WM.Resistance of personal risk perceptions to debiasing interventions.Health Psychol. 1995;14(2):132–140. doi:10.1037//0278-6133.14.2.132
Dietrich D, Olson M.A demonstration of hindsight bias using the Thomas confirmation vote.Psychol Rep. 1993;72(2):377-378. doi:/10.2466/pr0.1993.72.2.377
Lee KK.An indirect debiasing method: Priming a target attribute reduces judgmental biases in likelihood estimations.PLoS ONE. 2019;14(3):e0212609. doi:10.1371/journal.pone.0212609
Saposnik G, Redelmeier D, Ruff CC, Tobler PN.Cognitive biases associated with medical decisions: A systematic review.BMC Med Inform Decis Mak. 2016;16(1):138. doi:10.1186/s12911-016-0377-1
Furnham A., Boo HC.A literature review of anchoring bias.The Journal of Socio-Economics.2011;40(1):35-42. doi:10.1016/j.socec.2010.10.008
Loftus EF.Leading questions and the eyewitness report.Cognitive Psychology. 1975;7(4):560-572. doi:10.1016/0010-0285(75)90023-7
Challies DM, Hunt M, Garry M, Harper DN.Whatever gave you that idea? False memories following equivalence training: a behavioral account of the misinformation effect.J Exp Anal Behav. 2011;96(3):343-362. doi:10.1901/jeab.2011.96-343
Miyamoto R, Kikuchi Y.Gender differences of brain activity in the conflicts based on implicit self-esteem.PLoS ONE. 2012;7(5):e37901. doi:10.1371/journal.pone.0037901
Weinstein ND, Klein WM.Resistance of personal risk perceptions to debiasing interventions.Health Psychol. 1995;14(2):132–140. doi:10.1037//0278-6133.14.2.132
Gratton G, Cooper P, Fabiani M, Carter CS, Karayanidis F.Dynamics of cognitive control: theoretical bases, paradigms, and a view for the future.Psychophysiology. 2018;55(3). doi:10.1111/psyp.13016
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