Cognitive biases are systematic patterns of deviation from norm and/or rationality in judgment. They are often studied in psychology, sociology and behavioral economics.[1]
Although the reality of most of these biases is confirmed by reproducible research,[2][3] there are often controversies about how to classify these biases or how to explain them.[4] Several theoretical causes are known for some cognitive biases, which provides a classification of biases by their common generative mechanism (such as noisy information-processing[5]). Gerd Gigerenzer has criticized the framing of cognitive biases as errors in judgment, and favors interpreting them as arising from rational deviations from logical thought.[6]
Explanations include information-processing rules (i.e., mental shortcuts), called heuristics, that the brain uses to produce decisions or judgments. Biases have a variety of forms and appear as cognitive ("cold") bias, such as mental noise,[5] or motivational ("hot") bias, such as when beliefs are distorted by wishful thinking. Both effects can be present at the same time.[7][8]
There are also controversies over some of these biases as to whether they count as useless or irrational, or whether they result in useful attitudes or behavior. For example, when getting to know others, people tend to ask leading questions which seem biased towards confirming their assumptions about the person. However, this kind of confirmation bias has also been argued to be an example of social skill; a way to establish a connection with the other person.[9]
Although this research overwhelmingly involves human subjects, some findings that demonstrate bias have been found in non-human animals as well. For example, loss aversion has been shown in monkeys and hyperbolic discounting has been observed in rats, pigeons, and monkeys.[10]
These biases affect belief formation, reasoning processes, business and economic decisions, and human behavior in general.
The anchoring bias, or focalism, is the tendency to rely too heavily—to "anchor"—on one trait or piece of information when making decisions (usually the first piece of information acquired on that subject).[11][12] Anchoring bias includes or involves the following:
The tendency to perceive meaningful connections between unrelated things.[17] The following are types of apophenia:
The availability heuristic (also known as the availability bias) is 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.[20] The availability heuristic includes or involves the following:
Cognitive dissonance is the perception of contradictory information and the mental toll of it.
Confirmation bias is the tendency to search for, interpret, focus on and remember information in a way that confirms one's preconceptions.[31] There are multiple other cognitive biases which involve or are types of confirmation bias:
Egocentric bias is the tendency to rely too heavily on one's own perspective and/or have a different perception of oneself relative to others.[34] The following are forms of egocentric bias:
Extension neglect occurs where the quantity of the sample size is not sufficiently taken into consideration when assessing the outcome, relevance or judgement. The following are forms of extension neglect:
False priors are initial beliefs and knowledge which interfere with the unbiased evaluation of factual evidence and lead to incorrect conclusions. Biases based on false priors include:
The framing effect is the tendency to draw different conclusions from the same information, depending on how that information is presented. Forms of the framing effect include:
The following relate to prospect theory:
Name | Description |
---|---|
Action bias | The tendency for someone to act when faced with a problem even when inaction would be more effective, or to act when no evident problem exists.[89][90] |
Additive bias | The tendency to solve problems through addition, even when subtraction is a better approach.[91][92] |
Attribute substitution | Occurs when a judgment has to be made (of a target attribute) that is computationally complex, and instead a more easily calculated heuristic attribute is substituted. This substitution is thought of as taking place in the automatic intuitive judgment system, rather than the more self-aware reflective system. |
Curse of knowledge | When better-informed people find it extremely difficult to think about problems from the perspective of lesser-informed people.[93] |
Declinism | The predisposition to view the past favorably (rosy retrospection) and future negatively.[94] |
End-of-history illusion | The age-independent belief that one will change less in the future than one has in the past.[95] |
Exaggerated expectation | The tendency to expect or predict more extreme outcomes than those outcomes that actually happen.[5] |
Form function attribution bias | 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.[96] |
Fundamental pain bias | The tendency for people to believe they accurately report their own pain levels while holding the paradoxical belief that others exaggerate it.[97] |
Hedonic recall bias | The tendency for people who are satisfied with their wage to overestimate how much they earn, and vice versa, for people who are unsatisfied with their wage to underestimate it.[98] |
Hindsight bias | Sometimes called the "I-knew-it-all-along" effect, or the "Hindsight is 20/20" effect, is the tendency to see past events as having been predictable[99] before they happened. |
Impact bias | The tendency to overestimate the length or the intensity of the impact of future feeling states.[46] |
Information bias | The tendency to seek information even when it cannot affect action.[100] |
Interoceptive bias, Embodied cognition, or Hungry judge effect | The tendency for sensory input about the body itself to affect one's judgement about external, unrelated circumstances. (As for example, in parole judges who are more lenient when fed and rested.)[101][102][103][104] |
Mere exposure effect or familiarity principle (in social psychology) |
The tendency to express undue liking for things or acceptance of propaganda merely because of familiarity with or repeated exposure to them.[105] |
Money illusion | The tendency to concentrate on the nominal value (face value) of money rather than its value in terms of purchasing power.[106] |
Moral credential effect | Occurs when someone who does something good gives themselves permission to be less good in the future. |
Non-adaptive choice switching | After experiencing a bad outcome with a decision problem, the tendency to avoid the choice previously made when faced with the same decision problem again, even though the choice was optimal. Also known as "once bitten, twice shy" or "hot stove effect".[107] |
Omission bias | The tendency to judge harmful actions (commissions) as worse, or less moral, than equally harmful inactions (omissions).[108] |
Optimism bias | The tendency to be over-optimistic, underestimating greatly the probability of undesirable outcomes and overestimating favorable and pleasing outcomes (see also wishful thinking, valence effect, positive outcome bias, and compare pessimism bias).[109][110] |
Ostrich effect | Ignoring an obvious negative situation. |
Outcome bias | The tendency to judge a decision by its eventual outcome instead of the quality of the decision at the time it was made. |
Pessimism bias | The tendency for some people, especially those with depression, to overestimate the likelihood of negative things happening to them. (compare optimism bias) |
Present bias | The tendency of people to give stronger weight to payoffs that are closer to the present time when considering trade-offs between two future moments.[111] |
Plant blindness | The tendency to ignore plants in their environment and a failure to recognize and appreciate the utility of plants to life on earth.[112] |
Prevention bias | When investing money to protect against risks, decision makers perceive that a dollar spent on prevention buys more security than a dollar spent on timely detection and response, even when investing in either option is equally effective.[113] |
Probability matching | Sub-optimal matching of the probability of choices with the probability of reward in a stochastic context. |
Pro-innovation bias | 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. |
Projection bias | The tendency to overestimate how much one's future selves will share one's current preferences, thoughts and values, thus leading to sub-optimal choices.[114][115][116] |
Proportionality bias | Our innate tendency to assume that big events have big causes, may also explain our tendency to accept conspiracy theories.[117][118] |
Recency illusion | 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 (see also frequency illusion). Also recency bias is a cognitive bias that favors recent events over historic ones. A memory bias, recency bias gives "greater importance to the most recent event",[119] such as the final lawyer's closing argument a jury hears before being dismissed to deliberate. |
Systematic bias | Judgement that arises when targets of differentiating judgement become subject to effects of regression that are not equivalent.[120] |
Risk compensation or Peltzman effect | The tendency to take greater risks when perceived safety increases. |
Surrogation | 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. |
Teleological bias | The tendency to engage in overgeneralized ascriptions of purpose to entities and events that did not arise from goal-directed action, design, or selection based on functional effects.[121][122] |
Turkey illusion | Absence of expectation of sudden trend breaks in continuous developments |
Unit bias | 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.[123] |
Value selection bias | The tendency to rely on existing numerical data when reasoning in an unfamiliar context, even if calculation or numerical manipulation is required.[124][125] |
Weber–Fechner law | Difficulty in comparing small differences in large quantities. |
Association fallacies include:
Attribution bias includes:
Conformity is involved in the following:
Ingroup bias is the tendency for people to give preferential treatment to others they perceive to be members of their own groups. It is related to the following:
Name | Description |
---|---|
Assumed similarity bias | Where an individual assumes that others have more traits in common with them than those others actually do.[141] |
Outgroup favoritism | When some socially disadvantaged groups will express favorable attitudes (and even preferences) toward social, cultural, or ethnic groups other than their own.[142] |
Pygmalion effect | The phenomenon whereby others' expectations of a target person affect the target person's performance. |
Reactance | The urge to do the opposite of what someone wants one to do out of a need to resist a perceived attempt to constrain one's freedom of choice (see also Reverse psychology). |
Reactive devaluation | Devaluing proposals only because they purportedly originated with an adversary. |
Social comparison bias | The tendency, when making decisions, to favour potential candidates who do not compete with one's own particular strengths.[143] |
Shared information bias | The tendency for group members to spend more time and energy discussing information that all members are already familiar with (i.e., shared information), and less time and energy discussing information that only some members are aware of (i.e., unshared information).[144] |
Worse-than-average effect | A tendency to believe ourselves to be worse than others at tasks which are difficult.[145] |
In psychology and cognitive science, a memory bias is a cognitive bias that either enhances or impairs the recall of a memory (either the chances that the memory will be recalled at all, or the amount of time it takes for it to be recalled, or both), or that alters the content of a reported memory. There are many types of memory bias, including:
The misattributions include:
Name | Description |
---|---|
Availability bias | Greater likelihood of recalling recent, nearby, or otherwise immediately available examples, and the imputation of importance to those examples over others. |
Bizarreness effect | Bizarre material is better remembered than common material. |
Boundary extension | Remembering the background of an image as being larger or more expansive than the foreground[151] |
Childhood amnesia | The retention of few memories from before the age of four. |
Choice-supportive bias | The tendency to remember one's choices as better than they actually were.[152] |
Confirmation bias | The tendency to search for, interpret, or recall information in a way that confirms one's beliefs or hypotheses. See also under § Confirmation bias. |
Conservatism or Regressive bias | Tendency to remember high values and high likelihoods/probabilities/frequencies as lower than they actually were and low ones as higher than they actually were. Based on the evidence, memories are not extreme enough.[153][154] |
Consistency bias | Incorrectly remembering one's past attitudes and behaviour as resembling present attitudes and behaviour.[155] |
Continued influence effect | Misinformation continues to influence memory and reasoning about an event, despite the misinformation having been corrected.[156] cf. misinformation effect, where the original memory is affected by incorrect information received later. |
Context effect | That cognition and memory are dependent on context, such that out-of-context memories are more difficult to retrieve than in-context memories (e.g., recall time and accuracy for a work-related memory will be lower at home, and vice versa). |
Cross-race effect | The tendency for people of one race to have difficulty identifying members of a race other than their own. |
Egocentric bias | Recalling the past in a self-serving manner, e.g., remembering one's exam grades as being better than they were, or remembering a caught fish as bigger than it really was. |
Euphoric recall | The tendency of people to remember past experiences in a positive light, while overlooking negative experiences associated with that event. |
Fading affect bias | A bias in which the emotion associated with unpleasant memories fades more quickly than the emotion associated with positive events.[157] |
Generation effect (Self-generation effect) | That self-generated information is remembered best. For instance, people are better able to recall memories of statements that they have generated than similar statements generated by others. |
Gender differences in eyewitness memory | The tendency for a witness to remember more details about someone of the same gender. |
Google effect | The tendency to forget information that can be found readily online by using Internet search engines. |
Hindsight bias ("I-knew-it-all-along" effect) | The inclination to see past events as having been predictable. |
Humor effect | That humorous items are more easily remembered than non-humorous ones, which might be explained by the distinctiveness of humor, the increased cognitive processing time to understand the humor, or the emotional arousal caused by the humor.[158] |
Illusory correlation | Inaccurately seeing a relationship between two events related by coincidence.[159] See also under {{Section link}}: required section parameter(s) missing |
Illusory truth effect (Illusion-of-truth effect) | People are more likely to identify as true statements those they have previously heard (even if they cannot consciously remember having heard them), regardless of the actual validity of the statement. In other words, a person is more likely to believe a familiar statement than an unfamiliar one. See also under {{Section link}}: required section parameter(s) missing |
Lag effect | The phenomenon whereby learning is greater when studying is spread out over time, as opposed to studying the same amount of time in a single session. See also spacing effect. |
Leveling and sharpening | Memory distortions introduced by the loss of details in a recollection over time, often concurrent with sharpening or selective recollection of certain details that take on exaggerated significance in relation to the details or aspects of the experience lost through leveling. Both biases may be reinforced over time, and by repeated recollection or re-telling of a memory.[160] |
Levels-of-processing effect | That different methods of encoding information into memory have different levels of effectiveness.[161] |
List-length effect | A smaller percentage of items are remembered in a longer list, but as the length of the list increases, the absolute number of items remembered increases as well.[162] |
Memory inhibition | Being shown some items from a list makes it harder to retrieve the other items (e.g., Slamecka, 1968). |
Misinformation effect | Memory becoming less accurate because of interference from post-event information.[163] cf. continued influence effect, where misinformation about an event, despite later being corrected, continues to influence memory about the event. |
Modality effect | That memory recall is higher for the last items of a list when the list items were received via speech than when they were received through writing. |
Mood-congruent memory bias (state-dependent memory) | The improved recall of information congruent with one's current mood. |
Negativity bias or Negativity effect | Psychological phenomenon by which humans have a greater recall of unpleasant memories compared with positive memories.[164][116] (see also actor-observer bias, group attribution error, positivity effect, and negativity effect).[129] |
Next-in-line effect | When taking turns speaking in a group using a predetermined order (e.g. going clockwise around a room, taking numbers, etc.) people tend to have diminished recall for the words of the person who spoke immediately before them.[165] |
Part-list cueing effect | That being shown some items from a list and later retrieving one item causes it to become harder to retrieve the other items.[166] |
Peak–end rule | That people seem to perceive not the sum of an experience but the average of how it was at its peak (e.g., pleasant or unpleasant) and how it ended. |
Persistence | The unwanted recurrence of memories of a traumatic event. |
Picture superiority effect | The notion that concepts that are learned by viewing pictures are more easily and frequently recalled than are concepts that are learned by viewing their written word form counterparts.[167][168][169][170][171][172] |
Placement bias | Tendency to remember ourselves to be better than others at tasks at which we rate ourselves above average (also Illusory superiority or Better-than-average effect)[78] and tendency to remember ourselves to be worse than others at tasks at which we rate ourselves below average (also Worse-than-average effect).[173] |
Positivity effect (Socioemotional selectivity theory) | That older adults favor positive over negative information in their memories. See also euphoric recall |
Primacy effect | Where an item at the beginning of a list is more easily recalled. A form of serial position effect. See also recency effect and suffix effect. |
Processing difficulty effect | That information that takes longer to read and is thought about more (processed with more difficulty) is more easily remembered.[174] See also levels-of-processing effect. |
Recency effect | A form of serial position effect where an item at the end of a list is easier to recall. This can be disrupted by the suffix effect. See also primacy effect. |
Reminiscence bump | The recalling of more personal events from adolescence and early adulthood than personal events from other lifetime periods.[175] |
Repetition blindness | Unexpected difficulty in remembering more than one instance of a visual sequence |
Rosy retrospection | The remembering of the past as having been better than it really was. |
Saying is believing effect | Communicating a socially tuned message to an audience can lead to a bias of identifying the tuned message as one's own thoughts.[176] |
Self-relevance effect | That memories relating to the self are better recalled than similar information relating to others. |
Serial position effect | That items near the end of a sequence are the easiest to recall, followed by the items at the beginning of a sequence; items in the middle are the least likely to be remembered.[177] See also recency effect, primacy effect and suffix effect. |
Spacing effect | That information is better recalled if exposure to it is repeated over a long span of time rather than a short one. |
Spotlight effect | The tendency to overestimate the amount that other people notice one's appearance or behavior. |
Stereotype bias or stereotypical bias | Memory distorted towards stereotypes (e.g., racial or gender). |
Suffix effect | Diminishment of the recency effect because a sound item is appended to the list that the subject is not required to recall.[178][179] A form of serial position effect. Cf. recency effect and primacy effect. |
Subadditivity effect | The tendency to estimate that the likelihood of a remembered event is less than the sum of its (more than two) mutually exclusive components.[180] |
Tachypsychia | When time perceived by the individual either lengthens, making events appear to slow down, or contracts.[181] |
Telescoping effect | The tendency to displace recent events backwards in time and remote events forward in time, so that recent events appear more remote, and remote events, more recent. |
Testing effect | The fact that one more easily recall information one has read by rewriting it instead of rereading it.[182] Frequent testing of material that has been committed to memory improves memory recall. |
Tip of the tongue phenomenon | When a subject is able to recall parts of an item, or related information, but is frustratingly unable to recall the whole item. This is thought to be an instance of "blocking" where multiple similar memories are being recalled and interfere with each other.[148] |
Travis syndrome | Overestimating the significance of the present.[183] It is related to chronological snobbery with possibly an appeal to novelty logical fallacy being part of the bias. |
Verbatim effect | That the "gist" of what someone has said is better remembered than the verbatim wording.[184] This is because memories are representations, not exact copies. |
von Restorff effect | That an item that sticks out is more likely to be remembered than other items.[185] |
Zeigarnik effect | That uncompleted or interrupted tasks are remembered better than completed ones. |
As you might guess, the phenomenon is named after an incident in which I was talking to a friend about the Baader-Meinhof gang (and this was many years after they were in the news). The next day, my friend phoned me and referred me to an article in that day's newspaper in which the Baader-Meinhof gang was mentioned.
Young people, middle-aged people, and older people all believed they had changed a lot in the past but would change relatively little in the future.
The CIE refers to the tendency for information that is initially presented as true, but later revealed to be false, to continue to affect memory and reasoning