Ambiguity effect

Anchoring or focalism

Anthropocentric thinking

Anthropomorphism or personification

Attentional bias

Automation bias

Availability heuristic

Availability cascade

Backfire effect

Bandwagon effect

Base rate fallacy or Base rate neglect

Belief bias

Ben Franklin effect

Berkson's paradox

Bias blind spot

Choice-supportive bias

Clustering illusion

Confirmation bias

Congruence bias

Continued influence effect

Contrast effect

Courtesy bias

Curse of knowledge

Declinism

Decoy effect

Default effect

Denomination effect

Disposition effect

Distinction bias

Dread aversion

Dunning–Kruger effect

Duration neglect

Empathy gap

Endowment effect

Exaggerated expectation

Experimenter's or expectation bias

Focusing effect

Forer effect or Barnum effect

Form function attribution bias

Framing effect

Frequency illusion or Baader–Meinhof effect

Functional fixedness

Gambler's fallacy

Hard–easy effect

Hindsight bias

Hostile attribution bias

Hot-hand fallacy

Hyperbolic discounting

Identifiable victim effect

IKEA effect

Illicit transference

Illusion of control

Illusion of validity

Illusory correlation

Illusory truth effect

Impact bias

Information bias

Insensitivity to sample size

Irrational escalation

Law of the instrument

Less-is-better effect

Look-elsewhere effect

Loss aversion

Mere exposure effect

Money illusion

Moral credential effect

Negativity bias or Negativity effect

Neglect of probability

Normalcy bias

Not invented here

Observer-expectancy effect

Omission bias

Optimism bias

Ostrich effect

Outcome bias

Overconfidence effect

Pareidolia

Pessimism bias

Planning fallacy

Post-purchase rationalization

Pro-innovation bias

Projection bias

Pseudocertainty effect

Reactance

Reactive devaluation

Recency illusion

Regressive bias

Restraint bias

Rhyme as reason effect

Risk compensation / Peltzman effect

Selection bias

Selective perception

Semmelweis reflex

Sexual overperception bias / sexual underperception bias

Social comparison bias

Social desirability bias

Status quo bias

Stereotyping

Subadditivity effect

Subjective validation

Surrogation

Survivorship bias

Time-saving bias

Third-person effect

Parkinson's law of triviality

Unit bias

Weber–Fechner law

Well travelled road effect

Women are wonderful effect

Zero-risk bias

Zero-sum bias

The tendency to avoid options for which the probability of a favorable outcome is unknown.

The tendency to rely too heavily, or "anchor", on one trait or piece of information when making decisions (usually the first piece of information acquired on that subject).

The tendency to use human analogies as a basis for reasoning about other, less familiar, biological phenomena.

The tendency to characterize animals, objects, and abstract concepts as possessing human-like traits, emotions, and intentions.

The tendency of perception to be affected by recurring thoughts.

The tendency to depend excessively on automated systems which can lead to erroneous automated information overriding correct decisions.

The tendency to overestimate the likelihood of events with greater "availability" in memory, which can be influenced by how recent the memories are or how unusual or emotionally charged they may be.

A self-reinforcing process in which a collective belief gains more and more plausibility through its increasing repetition in public discourse (or "repeat something long enough and it will become true").

The reaction to disconfirming evidence by strengthening one's previous beliefs.

The tendency to do (or believe) things because many other people do (or believe) the same. Related to groupthink and herd behavior.

The tendency to ignore base rate information (generic, general information) and focus on specific information (information only pertaining to a certain case).

An effect where someone's evaluation of the logical strength of an argument is biased by the believability of the conclusion.

A person who has performed a favor for someone is more likely to do another favor for that person than they would be if they had received a favor from that person.

The tendency to misinterpret statistical experiments involving conditional probabilities.

The tendency to see oneself as less biased than other people, or to be able to identify more cognitive biases in others than in oneself.

The tendency to remember one's choices as better than they actually were.

The tendency to overestimate the importance of small runs, streaks, or clusters in large samples of random data (that is, seeing phantom patterns).

The tendency to search for, interpret, focus on and remember information in a way that confirms one's preconceptions.

The tendency to revise one's belief insufficiently when presented with new evidence.

The tendency to believe previously learned misinformation even after it has been corrected. Misinformation can still influence inferences one generates after a correction has occurred.

The enhancement or reduction of a certain stimulus' perception when compared with a recently observed, contrasting object.

The tendency to give an opinion that is more socially correct than one's true opinion, so as to avoid offending anyone.

When better-informed people find it extremely difficult to think about problems from the perspective of lesser-informed people.

The predisposition to view the past favorably (rosy retrospection) and future negatively.

Preferences for either option A or B change in favor of option B when option C is presented, which is completely dominated by option B (inferior in all respects) and partially dominated by option A.

When given a choice between several options, the tendency to favor the default one.

The tendency to spend more money when it is denominated in small amounts (e.g., coins) rather than large amounts (e.g., bills).

The tendency to sell an asset that has accumulated in value and resist selling an asset that has declined in value.

The tendency to view two options as more dissimilar when evaluating them simultaneously than when evaluating them separately.

Just as losses yield double the emotional impact of gains, dread yields double the emotional impact of savouring.

The tendency for unskilled individuals to overestimate their own ability and the tendency for experts to underestimate their own ability.

The neglect of the duration of an episode in determining its value.

The tendency to underestimate the influence or strength of feelings, in either oneself or others.

The tendency for people to demand much more to give up an object than they would be willing to pay to acquire it.

The tendency to expect or predict more extreme outcomes than those outcomes that actually happen.

The tendency for experimenters to believe, certify, and publish data that agree with their expectations for the outcome of an experiment, and to disbelieve, discard, or downgrade the corresponding weightings for data that appear to conflict with those expectations.

The tendency to place too much importance on one aspect of an event.

The observation that individuals will give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically for them, but are in fact vague and general enough to apply to a wide range of people. This effect can provide a partial explanation for the widespread acceptance of some beliefs and practices, such as astrology, fortune telling, graphology, and some types of personality tests.

In human–robot interaction, the tendency of people to make systematic errors when interacting with a robot. People may base their expectations and perceptions of a robot on its appearance (form) and attribute functions which do not necessarily mirror the true functions of the robot.

Drawing different conclusions from the same information, depending on how that information is presented.

The illusion in which a word, a name, or other thing that has recently come to one's attention suddenly seems to appear with improbable frequency shortly afterwards (not to be confused with the recency illusion or selection bias). This illusion is sometimes referred to as the Baader–Meinhof phenomenon.

Limits a person to using an object only in the way it is traditionally used.

The tendency to think that future probabilities are altered by past events, when in reality they are unchanged. The fallacy arises from an erroneous conceptualization of the law of large numbers. For example, "I've flipped heads with this coin five times consecutively, so the chance of tails coming out on the sixth flip is much greater than heads."

Based on a specific level of task difficulty, the confidence in judgments is too conservative and not extreme enough.

Sometimes called the "I-knew-it-all-along" effect, the tendency to see past events as being predictable at the time those events happened.

The "hostile attribution bias" is the tendency to interpret others' behaviors as having hostile intent, even when the behavior is ambiguous or benign.

The "hot-hand fallacy" (also known as the "hot hand phenomenon" or "hot hand") is the belief that a person who has experienced success with a random event has a greater chance of further success in additional attempts.

Discounting is the tendency for people to have a stronger preference for more immediate payoffs relative to later payoffs. Hyperbolic discounting leads to choices that are inconsistent over time – people make choices today that their future selves would prefer not to have made, despite using the same reasoning. Also known as current moment bias, present-bias, and related to Dynamic inconsistency. A good example of this: a study showed that when making food choices for the coming week, 74% of participants chose fruit, whereas when the food choice was for the current day, 70% chose chocolate.

The tendency to respond more strongly to a single identified person at risk than to a large group of people at risk.

The tendency for people to place a disproportionately high value on objects that they partially assembled themselves, such as furniture from IKEA, regardless of the quality of the end result.

Occurs when a term in the distributive (referring to every member of a class) and collective (referring to the class itself as a whole) sense are treated as equivalent. The two variants of this fallacy are the fallacy of composition and the fallacy of division.

The tendency to overestimate one's degree of influence over other external events.

Belief that our judgments are accurate, especially when available information is consistent or inter-correlated.

Inaccurately perceiving a relationship between two unrelated events.

A tendency to believe that a statement is true if it is easier to process, or if it has been stated multiple times, regardless of its actual veracity. These are specific cases of truthiness.

The tendency to overestimate the length or the intensity of the impact of future feeling states.

The tendency to seek information even when it cannot affect action.

The tendency to under-expect variation in small sample

The phenomenon where people justify increased investment in a decision, based on the cumulative prior investment, despite new evidence suggesting that the decision was probably wrong. Also known as the sunk cost fallacy.

An over-reliance on a familiar tool or methods, ignoring or under-valuing alternative approaches. "If all you have is a hammer, everything looks like a nail."

The tendency to prefer a smaller set to a larger set judged separately, but not jointly.

An apparently statistically significant observation may have actually arisen by chance because of the size of the parameter space to be searched.

The disutility of giving up an object is greater than the utility associated with acquiring it. (see also Sunk cost effects and endowment effect).

The tendency to express undue liking for things merely because of familiarity with them.

The tendency to concentrate on the nominal value (face value) of money rather than its value in terms of purchasing power.

The tendency of a track record of non-prejudice to increase subsequent prejudice.

Psychological phenomenon by which humans have a greater recall of unpleasant memories compared with positive memories.

The tendency to completely disregard probability when making a decision under uncertainty.

The refusal to plan for, or react to, a disaster which has never happened before.

Aversion to contact with or use of products, research, standards, or knowledge developed outside a group. Related to IKEA effect.

When a researcher expects a given result and therefore unconsciously manipulates an experiment or misinterprets data in order to find it (see also subject-expectancy effect).

The tendency to judge harmful actions (commissions) as worse, or less moral, than equally harmful inactions (omissions).

The tendency to be over-optimistic, overestimating favorable and pleasing outcomes (see also wishful thinking, valence effect, positive outcome bias).

Ignoring an obvious (negative) situation.

The tendency to judge a decision by its eventual outcome instead of based on the quality of the decision at the time it was made.

Excessive confidence in one's own answers to questions. For example, for certain types of questions, answers that people rate as "99% certain" turn out to be wrong 40% of the time.

A vague and random stimulus (often an image or sound) is perceived as significant, e.g., seeing images of animals or faces in clouds, the man in the moon, and hearing non-existent hidden messages on records played in reverse.

The tendency for some people, especially those suffering from depression, to overestimate the likelihood of negative things happening to them.

The tendency to underestimate task-completion times.

The tendency to persuade oneself through rational argument that a purchase was good value.

The tendency to have an excessive optimism towards an invention or innovation's usefulness throughout society, while often failing to identify its limitations and weaknesses.

The tendency to overestimate how much our future selves share one's current preferences, thoughts and values, thus leading to sub-optimal choices.

The tendency to make risk-averse choices if the expected outcome is positive, but make risk-seeking choices to avoid negative outcomes.

The urge to do the opposite of what someone wants you to do out of a need to resist a perceived attempt to constrain your freedom of choice (see also Reverse psychology).

Devaluing proposals only because they purportedly originated with an adversary.

The illusion that a phenomenon one has noticed only recently is itself recent. Often used to refer to linguistic phenomena; the illusion that a word or language usage that one has noticed only recently is an innovation when it is in fact long-established.

A certain state of mind wherein high values and high likelihoods are overestimated while low values and low likelihoods are underestimated.

The tendency to overestimate one's ability to show restraint in the face of temptation.

Rhyming statements are perceived as more truthful. A famous example being used in the O.J Simpson trial with the defense's use of the phrase "If the gloves don't fit, then you must acquit."

The tendency to take greater risks when perceived safety increases.

The tendency to notice something more when something causes us to be more aware of it, such as when we buy a car, we tend to notice similar cars more often than we did before. They are not suddenly more common – we just are noticing them more. Also called the Observational Selection Bias.

The tendency for expectations to affect perception.

The tendency to reject new evidence that contradicts a paradigm.

The tendency to over-/underestimate sexual interest of another person in oneself.

The tendency, when making decisions, to favour potential candidates who don't compete with one's own particular strengths.

The tendency to over-report socially desirable characteristics or behaviours in oneself and under-report socially undesirable characteristics or behaviours.

The tendency to like things to stay relatively the same.

Expecting a member of a group to have certain characteristics without having actual information about that individual.

The tendency to judge probability of the whole to be less than the probabilities of the parts.

Perception that something is true if a subject's belief demands it to be true. Also assigns perceived connections between coincidences.

Losing sight of the strategic construct that a measure is intended to represent, and subsequently acting as though the measure is the construct of interest.

Concentrating on the people or things that "survived" some process and inadvertently overlooking those that didn't because of their lack of visibility.

Underestimations of the time that could be saved (or lost) when increasing (or decreasing) from a relatively low speed and overestimations of the time that could be saved (or lost) when increasing (or decreasing) from a relatively high speed.

Belief that mass communicated media messages have a greater effect on others than on themselves.

The tendency to give disproportionate weight to trivial issues. Also known as bikeshedding, this bias explains why an organization may avoid specialized or complex subjects, such as the design of a nuclear reactor, and instead focus on something easy to grasp or rewarding to the average participant, such as the design of an adjacent bike shed.

The standard suggested amount of consumption (e.g., food serving size) is perceived to be appropriate, and a person would consume it all even if it is too much for this particular person.

Difficulty in comparing small differences in large quantities.

Underestimation of the duration taken to traverse oft-traveled routes and overestimation of the duration taken to traverse less familiar routes.

A tendency to associate more positive attributes with women than with men.

Preference for reducing a small risk to zero over a greater reduction in a larger risk.

A bias whereby a situation is incorrectly perceived to be like a zero-sum game (i.e., one person gains at the expense of another).