Confirmation bias is the tendency to look for, remember, and prefer information that aligns with your existing beliefs and values. It’s something humans naturally do, especially for long-held beliefs or beliefs with strong emotions attached to them, but it can have negative consequences. While no one can eliminate confirmation bias from their brains, you can recognize it when it happens. In this article, we’ll describe 15 examples of confirmation bias in action.
|4||The placebo effect|
|6||Criminal justice system|
|15||Climate change denial|
#1. Political bias
People who strongly identify with a specific political party tend to only seek out news and sources favoring that party. In most places, it’s fairly easy to stick with sources that lean politically one way or the other. Social media algorithms are also designed to keep people in their political bubbles, so many people don’t even need to intentionally avoid negative or opposing viewpoints. When people do encounter information that paints their party in a negative light, confirmation bias drives them to dismiss it, question its credibility, or forget they even saw it. Many people are even able to reframe negative information as positive, so their support of their party doesn’t have to shift.
#2. Financial investments
For many people, financial investments are a serious decision. It’s common to only pay attention to information that supports the decision you make. No one wants to hear they’ve made a horrible choice and they’re going to lose all their money. Investors often dismiss or explain away negative information. This can cause people to fall prey to the “sunk cost fallacy,” which is a phenomenon that leads people to invest more into a failing strategy simply because they’re already invested in it. By only paying attention to positive news about an investment, you miss the whole picture and can end up losing even more money.
#3. Healthcare decisions
Because of personal experiences, research, or what they’ve heard from trusted friends and family, many people believe certain things about healthcare treatments, doctors, and other aspects of health and wellness. As an example, someone who believes in natural or alternative medicine will seek out information and evidence that supports the effectiveness of those treatments. Any information that questions or contradicts the effectiveness of treatments is dismissed. Often, the source itself doesn’t matter. If a more mainstream study supports an alternative treatment, a person will use that to defend their decision, but if another mainstream study contradicts it, they’ll dismiss that particular research. As healthcare decisions can be a matter of life or death, this type of confirmation bias can have serious consequences.
#4. The placebo effect
Placebos are used in clinical trials to assess the effectiveness of treatments. One group gets the real treatment while others get the placebo, which is often a sugar pill or inert injection. Many patients on the placebo experience benefits, although they’re purely psychological. This is known as the “placebo effect,” and it needs to be accounted for when researchers measure the results at the end of the trial. The placebo effect is its own cognitive bias, but confirmation bias is a part of it. As an example, if someone hopes they’ve gotten the real treatment as opposed to the placebo, they’ll only pay attention to signs of good health. On the other hand, if they have reasons to believe they’ve gotten the placebo, they’re more likely to only pay attention to worsening symptoms. This is known as the “nocebo effect.”
#5. Academic research
Confirmation bias is one of the most common and damaging problems academic researchers encounter. It can infect every step in the process. First, it can affect how researchers frame their hypotheses and questions. As an example, a study might ask, “To what extent does regularly drinking green tea contribute to weight loss?” This assumes that green tea and weight loss are linked. As the study continues, researchers could become further affected by confirmation bias as they may ignore information that doesn’t support the link. Confirmation bias can also impact the data analysis, reporting, and even the publishing stage. Publishers are run by people with their own biases, which may affect what studies get published and which are rejected.
#6. Criminal justice system
The criminal justice system is a bit like academia in that bias can affect the questions the police ask, how they collect information, and how the justice system responds to a crime. If a detective develops a theory about a crime right away, they may only look for and accept data that supports that theory. Once a suspect has been identified, confirmation bias can then affect how they’re treated, how juries see them, and what type of sentence they receive.
If you’re already interested in a product, confirmation bias may lead you to only pay attention to positive reviews. On the other hand, if you’re less sure about the product or believe there’s something better out there, you may only focus on the negative reviews. If your family grew up buying and loving a certain brand, you’re more likely to ignore its downsides and focus only on the positives even as you get older and have different experiences with a product. Marketing plays a big role in how we perceive brands, as well. Companies understand confirmation bias and try to harness its power to keep its customers loyal.
Horoscopes are astrological charts that represent the positions of the moon, sun, and planets during the time of an event, such as a person’s birth. Astrologers use these charts to offer insight and predictions about a person’s life. The scientific community doesn’t accept astrology as a science, but many people find meaning and peace through the practice. Confirmation bias can lead people to only believe in the horoscopes that affirm what they want to believe. As an example, if someone is looking for a new job, they’ll only remember the horoscopes that talk about career success or exciting new horizons.
Fandoms are communities of dedicated fans. They may revolve around a specific celebrity, media properties, sports, hobbies, and other areas of interest. Areas with large fandoms include Star Wars, the Marvel Universe, anime, K-pop group BTS, and singer Taylor Swift. Fandoms are subject to confirmation bias in that they tend to only seek out information and perspectives that align with their existing beliefs about their topic of interest. If evidence that contradicts their beliefs emerges, fandom members tend to ignore or dismiss it. They may even become defensive when they hear criticism or opinions they don’t agree with. When reinforced by other fandom members, a fan can become even further invested in their beliefs and more susceptible to confirmation bias.
Confirmation bias can affect a person’s self-image, whether that’s positive or negative. If a person has a positive view of themselves, they’re more likely to only remember behaviors and experiences that support that view. As an example, if someone considers themselves an excellent gift-giver, they’ll only remember the times they gave someone gifts that were very well-received while forgetting the times a gift was not thought out. On the other hand, if someone has a negative self-image, they’ll dwell on their mistakes and failures while ignoring the times they experienced success.
#11. Religious beliefs
For those with religious beliefs, faith is complex and personal. It’s not immune from confirmation bias. It can lead a person to only seek out sources that support their view, only listen to spiritual leaders who agree with them, and disregard members of the same faith with different views. As an example, if someone believes in certain interpretations of the Christian Bible, they’re likely to ignore contradictory perspectives and information. That even applies to contradictory information found in the Bible itself.
#12. Conspiracy theories
Belief in debunked conspiracy theories is one of the most powerful examples of confirmation bias. To support a belief, such as the earth is flat, conspiracy theorists will sift through lots of information, but only pick what affirms their existing beliefs. It doesn’t matter how far-flung those sources are or how many other sources contradict the belief. Confirmation bias also drives conspiracy theorists to find communities that agree with them, which makes it even easier for them to deny contradictory evidence. Conspiracy theorists are also more likely to misunderstand unclear or vague information as they assume it must support their views, regardless of the author’s intent.
#13. Climate change denial
97% of climate scientists agree that humans cause climate change, but those who deny climate change only pay attention to the other 3% of scientists. This is a textbook example of confirmation bias. Even in the face of mountains of evidence, climate change deniers pick the few studies denying or dismissing climate change because they support their existing beliefs. They’re also likely to spend lots of time around media and people who agree with them, which makes it seem as if their views are more accepted than they actually are.
#14. Gender stereotypes
Gender stereotypes can be positive or negative, but they all flatten the diversity of human experiences, behaviors, and personalities. Many people grow up in environments laced with gender stereotypes, and as they get older, they may succumb to confirmation bias. As an example, a person may believe that women are more emotional than men. Confirmation bias leads them to only recognize instances of women displaying more emotions while ignoring examples of men expressing anger, grief, or joy.
#15. Racial stereotypes
Like gender stereotypes, racial stereotypes can be positive or negative, but all cause harm in their own way. When someone holds a certain view of an ethnicity (either their own or someone else’s), they only pay attention to evidence that affirms that belief. For example, many believe in the stereotype that Asian people are inherently good at math, so they’ll point to the number of Asian people working in fields like science or engineering. However, they’ll then ignore all the evidence showing that math is a skill developed with practice and hard work; it’s not something people are born good at.