156 cognitive biases
Complete encyclopedia of cognitive biases and heuristics that affect your decisions.
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Showing: 156 biases
Confirmation bias
The tendency to search for, interpret, and remember information in a way that confirms our preexisting beliefs.
Anchoring effect
Over-reliance on the first piece of information encountered (the "anchor") when making decisions.
Sunk cost fallacy
Continuing an action because of already incurred costs, rather than evaluating future benefits.
Availability heuristic
Judging the likelihood of events based on how easily examples come to mind.
Loss aversion
Losses are psychologically about twice as powerful as equivalent gains.
Framing effect
Making different decisions depending on how the same information is presented.
Hindsight bias
The belief, after an event, that it was predictable ("I knew it all along").
Authority bias
Attributing greater credibility to opinions of people perceived as authorities.
Social proof
Following the actions of others in uncertain situations.
Halo effect
One positive trait influences the assessment of the entire person or product.
Optimism bias
The belief that we are less likely to experience negative events than others.
Dunning-Kruger effect
People with low competence overestimate their abilities, while experts underestimate theirs.
Bandwagon effect
Adopting beliefs or behaviors because many others do so.
Status quo bias
Preference for the current state of affairs, resistance to change.
Recency bias
Giving more weight to recent events than earlier ones.
Overconfidence bias
Overestimating one's own knowledge, skills, or prediction accuracy.
Endowment effect
Assigning greater value to things we own than to identical things we don't have.
Groupthink
The desire for harmony in a group leads to overlooking critical evaluation and alternative views.
Gambler's fallacy
The belief that past random events affect the probability of future ones.
Spotlight effect
Overestimating how much others pay attention to us.
Representativeness heuristic
Judging probability based on similarity to a typical case.
Base rate neglect
Ignoring general statistics in favor of specific information.
Conjunction fallacy
Assuming a detailed scenario is more likely than a general one.
Hot hand fallacy
The belief that a series of successes increases the chances of another success.
Neglect of probability
Ignoring probability when assessing risk, focusing on possibility of occurrence.
Zero-risk bias
Preferring complete elimination of a small risk over significant reduction of a larger one.
Affect heuristic
Making decisions based on current emotions rather than objective analysis.
Choice overload
Too many options lead to decision paralysis or worse choices.
Decoy effect
Adding an inferior option makes another option seem more attractive.
Rhyme-as-reason effect
Rhyming statements seem more truthful.
IKEA effect
Assigning greater value to things we created or assembled ourselves.
Peak-end rule
We judge experiences mainly based on their peak moment and ending.
Rosy retrospection
Remembering the past as better than it actually was.
Telescoping effect
Recent events seem more distant, while old events seem closer.
Leveling and sharpening
When retelling stories, we sharpen some details and flatten others.
Misinformation effect
Later information distorts memories of earlier events.
Cryptomnesia
Confusing others' ideas with your own, unconscious plagiarism.
Egocentric bias
Remembering the past in ways that present us in a better light.
Consistency bias
The belief that our current views have always been the same.
Self-serving bias
Attributing successes to ourselves and failures to external factors.
Fundamental attribution error
Attributing others' behavior to their character, but our own to circumstances.
Actor-observer asymmetry
Different explanations for the same behaviors in ourselves and others.
Just-world hypothesis
The belief that people get what they deserve.
In-group favoritism
Preferring members of your own group over outsiders.
Out-group homogeneity
Perceiving members of other groups as more similar to each other.
Moral credential effect
Past good deeds "entitle" us to later unethical behavior.
Belief perseverance
Maintaining beliefs despite evidence refuting them.
Semmelweis reflex
Automatic rejection of new evidence contradicting established norms.
Backfire effect
Contrary evidence strengthens existing beliefs instead of weakening them.
Reactive devaluation
Rejecting proposals simply because they come from an "opponent."
Naïve realism
The belief that we see the world objectively, while others are biased.
Bias blind spot
Recognizing biases in others but not in ourselves.
False consensus effect
Overestimating how many people agree with our views.
False uniqueness effect
Underestimating how many people have similar positive traits.
Illusion of control
The belief that we have influence over random events.
Illusion of validity
Excessive confidence in predictions based on consistent patterns.
Planning fallacy
Underestimating time, costs, and risks; overestimating benefits.
Hyperbolic discounting
Preferring smaller rewards now over larger ones later.
Present bias
Placing disproportionate weight on immediate benefits.
Projection bias
Assuming our current preferences will persist in the future.
Restraint bias
Overestimating our ability to resist temptation.
Impact bias
Overestimating the lasting emotional impact of future events.
Distinction bias
Overestimating differences when directly comparing options.
Functional fixedness
Difficulty seeing alternative uses for objects.
Denomination effect
Reluctance to spend large denominations compared to small ones.
Money illusion
Focusing on nominal value of money rather than real value.
Mental accounting
Treating money differently depending on its "category."
Bizarreness effect
We remember bizarre things better than ordinary ones.
Generation effect
We remember information we generated ourselves better.
Picture superiority effect
Images are remembered better than words.
Humor effect
Funny things are remembered better.
Spacing effect
Information spread over time is remembered better than cramming.
Serial position effect
Better remembering of first and last items on a list.
Suffix effect
Additional information at the end of a list weakens memory of last items.
Google effect
Poorer memory for information that can be easily searched online.
Next-in-line effect
Poor memory of what the predecessor said just before our turn.
Testing effect
Information is better retained when actively retrieved, not just read.
Tip-of-the-tongue phenomenon
The feeling that we almost remember a word but can't retrieve it.
Cheerleader effect
People seem more attractive in a group than individually.
Contrast effect
Our assessment of something changes depending on what it's compared to.
Focusing effect
Placing too much weight on one aspect of an event.
Frequency illusion (Baader-Meinhof)
After noticing something new, we start seeing it "everywhere."
Clustering illusion
Seeing patterns in random sequences of data.
Texas sharpshooter fallacy
Fitting a hypothesis to data after the fact, ignoring non-fitting data.
Survivorship bias
Focusing on successes, ignoring invisible failures.
Outcome bias
Judging decision quality based on outcome, not process.
Normalcy bias
Underestimating the probability and effects of a disaster.
Appeal to probability
Treating possibility as certainty.
Subadditivity effect
The sum of probabilities of detailed events > probability of the general event.
Murphy's law
"Whatever can go wrong, will go wrong" - selective memory of failures.
Curse of knowledge
Difficulty imagining that someone doesn't know what we know.
Illusion of transparency
Overestimating how well others can read our emotions.
Hard-easy effect
Overconfidence in hard tasks, underconfidence in easy ones.
Above-average effect
Most people consider themselves better than average (mathematically impossible).
Worse-than-average effect
In very difficult tasks, people underestimate their abilities.
Defensive attribution
Blaming victims to protect ourselves from anxiety.
Trait ascription bias
Perceiving ourselves as more variable than others.
Effort justification
Assigning greater value to things that required a lot of effort.
Ben Franklin effect
People who have done us a favor like us more.
Bystander effect
The more witnesses, the lower the chance someone will help.
System justification
Tendency to defend the status quo and existing systems.
Well-traveled road effect
A familiar route seems shorter than an unfamiliar one of the same length.
Cross-race effect
Difficulty distinguishing faces of people from other ethnic groups.
Negativity bias
Negative information has greater impact than positive.
Positivity effect
Older people remember and notice more positive information.
Forer effect (Barnum effect)
Accepting general descriptions as accurately describing oneself.
Pygmalion effect
Higher expectations lead to better performance.
Golem effect
Lower expectations lead to worse performance.
Placebo effect
Expectation of an effect causes an actual change.
Nocebo effect
Negative expectations cause negative effects.
Mere exposure effect
We prefer things we have frequent contact with.
Propinquity effect
We more often befriend people physically close to us.
Similarity-attraction effect
We like people similar to us.
"Beautiful is good" stereotype
Attributing positive character traits to attractive people.
Ambiguity effect
Avoiding options with unknown probability.
Risk compensation
Increasing risky behavior when feeling safer.
Peltzman effect
Safety regulations lead to riskier behavior.
Pseudocertainty effect
Different decisions for the same problem depending on framing.
Omission bias
Perceiving harm from action as worse than equal harm from inaction.
Commission bias
Tendency to act even when inaction would be better.
Unit bias
Tendency to eat/use the whole "unit" regardless of its size.
Law of triviality (bikeshedding)
Spending disproportionately much time on trivial issues.
Rhyme as reason effect
Rhyming statements seem more true.
Continued influence effect
Debunked information continues to influence our thinking.
Illusory correlation
Seeing relationships between unrelated events.
Selection bias
Drawing conclusions from non-representative data.
Observer-expectancy effect
Researcher expectations unconsciously influence study results.
Ostrich effect
Avoiding negative information.
Information bias
Seeking more information than needed for a decision.
Automation bias
Excessive trust in automated systems.
Digital amnesia
Forgetting information that can be found on the internet.
Psychological reactance
Opposition to something when we feel our freedoms are being restricted.
Reverse psychology
Using reactance for manipulation.
Naïve allocation
Dividing resources equally instead of optimally.
Less-is-better effect
Preferring smaller quantity of high quality over larger quantity of mixed quality.
Conjunction effect
Separate evaluation of products gives different results than joint evaluation.
Identifiable victim effect
Greater empathy toward a specific person than a group.
Scope insensitivity
Lack of proportional response to differences in scale.
Compassion fade
Decline in empathy as the number of victims increases.
Identifiable perpetrator effect
Greater anger at a specific perpetrator than at an abstract system.
Denomination effect
Greater tendency to spend small change than bills.
Drop-in-the-bucket effect
Giving up on action because it seems insignificant given the scale of the problem.
Zero-sum bias
Treating situations as zero-sum games when they are not.
Proportionality bias
Expecting proportionality between cause and effect.
Congruence bias
Testing only direct hypotheses, ignoring alternatives.
Belief bias
Evaluating an argument based on the believability of the conclusion.
Expectation bias
Perceiving things according to expectations.
Attentional bias
Selectively paying attention to certain stimuli.
Selective perception
Perceiving reality through the lens of one's own beliefs.
Wishful thinking
Believing something because we want it to be true.
Empathy gap
Underestimating the influence of emotional states on decisions.
Moral luck
Judging morality based on outcome, not intention.
Rule of three
Three examples seem more convincing than one or two.
Spotlight effect
Overestimating how much others notice us.
Illusion of asymmetric insight
Believing we understand others better than they understand us.
Naive cynicism
Assuming others are more self-interested than they actually are.