List of Cognitive Biases

Why people behave the way they do

Rational Judgment is the ability to reason to form an opinion objectively, independent of sensation, perception, feeling and desire.
Acting rationally requires one to respond correctly to reason, alone.

Cognitive bias is a systematic error in the ability to reason, affecting how some people process information, perceive others, and make decisions. It can lead to irrational thoughts or judgments and is often based on our perceptions, memories, or individual and societal beliefs.

Broadly speaking, bias is a tendency to lean in favour of or against a person, group, idea, or thing, usually in an unfair way. Biases are natural, they are a product of human nature, and they don’t simply exist in a vacuum or in our minds, they affect the way we make decisions and act.

In psychology, there are two main branches of biases. Conscious and unconscious.

Explicit or conscious bias is intentional, that is to say you are aware of your attitudes and the behaviours resulting from them.
Explicit bias can be good because it helps provide you with a sense of identity and can lead you to make good decisions (for example, being biased towards healthy foods).

However, these biases can often be dangerous when they take the form of conscious stereotyping.

On the other hand, unconscious bias, or cognitive bias, represents a set of unintentional biases and you are unaware of your attitudes and behaviours resulting from them.

Cognitive bias is often a result of your brain’s attempt to simplify information processing. Humans receive roughly 11 million bits of information per second. The problem is we can only process about 40 bits of information per second.

Therefore, we often rely on mental shortcuts (called heuristics) to help make sense of the world with relative speed. As such, these errors tend to arise from problems related to thinking: memory, attention, and other mistakes.

Cognitive biases can be beneficial because they do not require much mental effort and can allow you to make decisions relatively quickly, but like conscious biases, unconscious biases can also take the form of harmful prejudice that serves to hurt an individual or a group.

The following is a list of cognitive biases with a ‘brief’ explanation of each, that determine outcomes of many people when faced with situations in their everyday lives, demonstrating how many are wired to misjudge!

Action Bias

Why do we prefer doing something to doing nothing?

The action bias describes our tendency to favour action over inaction, often to our benefit. However, there are times when we feel compelled to act, even if there’s no evidence that it will lead to a better outcome than doing nothing would. Our tendency to respond with action as a default, automatic reaction, even without solid rationale to support it, has been termed the action bias.

Affect Heuristic

Why do we rely on our current emotions when making quick decisions?

The affect heuristic describes how we often rely on our emotions, rather than concrete information, when making decisions. This allows us to reach a conclusion quickly and easily but can also distort our thinking and lead us to make suboptimal choices.

Ambiguity Effect

Why do we prefer options we know?

The ambiguity effect describes how we tend to avoid options that we consider to be ambiguous or missing information. We dislike uncertainty and are therefore more inclined to select an option where the probability of achieving a favourable outcome is known.

Anchoring Bias

Why do we compare everything to the first piece of information we received?

The anchoring bias is a cognitive bias that causes us to rely heavily on the first piece of information we are given about a topic. When we are setting plans or making estimates about something, we interpret newer information from the reference point of our anchor instead of seeing it objectively. This can skew our judgment and prevent us from updating our plans or predictions as much as we should.

Attentional Bias

Why do we focus more on some things than others?

The attentional bias describes our tendency to focus on certain elements of our environment while ignoring others. Research has shown that many different factors can bias our attention, from external events and emotional stimuli (such as a perceived threat to our safety) to internal states (such as hunger or sadness).

Authority Bias

Why do we always trust the doctor, even though they might be wrong?

The authority bias describes our tendency to be more influenced by the opinions and judgments of authority figures. This bias can lead people to accept information or follow instructions without critically evaluating the content, simply because it comes from a perceived authority.

Availability Heuristic

Why do we tend to think that things that happened recently are more likely to happen again?

The availability heuristic describes our tendency to use information that comes to mind quickly and easily when making decisions about the future.

Bandwagon Effect

Why do we support opinions as they become more popular?

The Bandwagon effect refers to our habit of adopting certain behaviours or beliefs because many other people do the same.

Barnum Effect

Why do we believe our horoscopes?

The Barnum effect, also commonly referred to as the ‘Forer Effect’, describes when individuals believe that generic information, which could apply to anyone, applies specifically to themselves.

Base Rate Fallacy

Why do we rely on specific information over statistics?

When provided with both individuating information, which is specific to a certain person or event, and base rate information, which is objective, statistical information, we tend to assign greater value to the specific information and often ignore the base rate information altogether. This is referred to as the base rate fallacy or base rate neglect.

Belief Perseverance (The Backfire Effect)

Why do we maintain the same beliefs, even when we are proved wrong?

Belief perseverance, also known as the backfire effect or conceptual conservatism, describes how we continue to hold onto established beliefs even when faced with clear, contradictory evidence. We tend to prioritise our initial conclusions and resist changing our minds, even when it might be in our best interest to do so.

Benjamin Franklin effect

Why do we like someone more after doing them a favour?

The Benjamin Franklin effect describes how doing a favour for someone can actually make us feel more positively towards that person. The phenomenon is named after Benjamin Franklin, one of the Founding Fathers of the United States of America, who wrote about the concept in his autobiography.

Bikeshedding

Why do we focus on trivial things?

Bikeshedding, also known as Parkinson’s law of triviality, describes our tendency to devote a disproportionate amount of our time to menial and trivial matters while leaving important practical matters unattended.

Bottom-Dollar Effect

Why do we transfer negative emotions about being broke on items that we purchase?

The bottom dollar effect describes our tendency to dislike products and services that exhaust our remaining budget. We are less satisfied with our purchases if they cause a strain on our finances.

Bounded Rationality

Why are we satisfied by “good enough?”

Bounded rationality is a human decision-making process in which we attempt to satisfice, rather than optimize. In other words, we seek a decision that will be good enough, rather than the best possible decision.

Bundling Bias

Why do we value items purchased in a bundle less than those purchased individually?

The bundling bias describes our tendency not to use up all the experiences that are bought as a group, which means that we don’t get the full value of a bundle compared to an individual purchase.

Bye-Now Effect

Why are we likely to spend more after reading the word “bye”?

The bye-now effect describes the tendency for consumers to think of the word “buy” when they see the word “bye”. This priming effect, triggered by the homophone for “buy”, can subtly influence consumer behaviour and lead to increased spending or impulse buying.

Cashless Effect

Why does paying without physical cash increase the likelihood that we purchase something?

The cashless effect describes our tendency to be more willing to pay when there is no physical money involved in a transaction. It means that we are more likely to purchase something on a credit card than if we have to pay for it with cash.

Category Size Bias

Why do we think we’re more likely to win at the big casino versus the small one?

Category size bias describes our tendency to believe outcomes are more likely to occur if they are part of a large category rather than part of a small category, even if each outcome is equally likely. While the bias is based on experimental studies that have been successfully replicated, the interpretation of the evidence remains mixed.

Choice Overload

Why do we have a harder time choosing when we have more options?

Choice overload, also known as over choice, choice paralysis, or the paradox of choice, describes how people get overwhelmed when they are presented with many options. While we tend to assume that more choice is a good thing, research has shown that, in many cases, we have a harder time choosing from a larger array of options.

Cognitive Dissonance

Why is it so hard to change someone’s beliefs?

Cognitive dissonance is the psychological discomfort we experience when we hold two or more conflicting beliefs, attitudes, or values simultaneously. To resolve this tension, we often change, justify, or ignore the conflicting information.

Commitment Bias

Why do people support their past ideas, even when presented with evidence that they’re wrong?

Commitment bias, also known as the escalation of commitment, describes our tendency to remain committed to our past behaviours, particularly those exhibited publicly, even if they do not have desirable outcomes.

Confirmation Bias

Why do we favour our existing beliefs?

The confirmation bias describes our underlying tendency to notice, focus on, and give greater credence to evidence that fits with our existing beliefs. It’s also a way of enhancing and protecting our self-esteem.
As with the self-serving bias (see below), our minds choose to reinforce our preexisting ideas because being right helps preserve our sense of self-esteem, which is important for feeling secure in the world and maintaining positive relationships.

Decision Fatigue

Why do we make worse decisions at the end of the day?

Decision fatigue describes how our decision-making gets worse as we make additional choices and our cognitive abilities get worn out. Decision fatigue is the reason we feel overwhelmed when we have too many choices to make.

Declinism

Why do we think the past is better than the future?

Declinism is the tendency to see the past in an overly positive light and to view the present or future in an overly negative light, leading us to believe that things are worse than they used to be. Declinism is often a feeling harboured about the overall state of a country, society, or institution, with the view that it is in decline or getting worse.

Decoy Effect

Why do we feel more strongly about one option after a third one is added?

The decoy effect describes how, when we are choosing between two alternatives, the addition of a third, less attractive option (the decoy) can influence our perception of the original two choices. Decoys are ‘asymmetrically dominated’, they are completely inferior to one option (the target) but only partially inferior to the other (the competitor). For this reason, the decoy effect is sometimes called the ‘asymmetric dominance effect’.

Disposition Effect

Why do we tend to hold on to losing investments?

The disposition effect refers to our tendency to prematurely sell assets that have made financial gains, while holding on to assets that are losing money. We are driven to sell our winning investments in order to ensure a profit but are averse to selling losing investments in hopes of turning them into gains.

Distinction Bias

Why do we view options as more distinct when evaluating them simultaneously?

Distinction bias describes how, in decision-making, we tend to overvalue the differences between two options when we examine them together. Conversely, we consider these differences to be less important when we evaluate the options separately.

Dunning-Kruger Effect

Why do we fail to accurately gauge our own abilities?

The Dunning-Kruger effect occurs when a person’s lack of knowledge and skill in a certain area causes them to overestimate their own competence. By contrast, this effect also drives those who excel in a given area to think the task is simple for everyone, leading them to underestimate their abilities.

Einstellung Effect

Why do our past experiences prevent us from reaching the best possible outcome?

The Einstellung effect describes when we approach a problem with a mindset that worked for us in the past, even if a more efficient solution exists. This hinders one’s ability to enhance their creativity and problem-solving skills as they don’t consider other perspectives or options.

Empathy Gap

Why do we mis predict how much our emotions influence our behaviour?

The empathy gap describes our tendency to underestimate the influence of varying mental states on our own behaviour and make decisions that only satisfy our current emotion, feeling, or state of being.

Endowment Effect

Why do we value items more if they belong to us?

The endowment effect describes how people tend to value items that they own more highly than they would if they did not belong to them. This means that sellers often try to charge more for an item than it would cost elsewhere.

Experience Bias (Curse of knowledge)

Why do we take our own perception to be the objective truth?

The experience bias relates to the tendency to attribute our past experiences and ways of applying prior knowledge, particularly in decision making. ‘The boy who cried wolf’ although not intended to illustrate this bias is an example; the boy has made 2 similar claims before this, and they’re both lies. Conclusion: The boy’s 3rd claim about the wolf attacking his town’s flock, therefore, must also be a lie so will not happen.
(This also relates to the ‘Genetic fallacy’ listed below)

Extrinsic Incentive Bias

Why do we think others are in it for the money, but we’re in it for the experience?

The extrinsic incentive bias relates to the tendency to attribute other people’s motives to extrinsic incentives, such as job security or high wages, rather than intrinsic ones, such as learning new things or building a new skill.

False Consensus Effect

Why do we overestimate agreement?

The false consensus effect describes how individuals frequently overestimate how much others share their beliefs, values, and behaviours. This implies that people often project their personal attitudes and ideas onto others, assuming they are more common or widespread than they actually are.

Framing Effect

Why do our decisions depend on how options are presented to us?

The framing effect is when our decisions are influenced by the way information is presented. Equivalent information can be more or less attractive depending on what features are highlighted.

Functional Fixedness

Why do we have trouble thinking outside the box?

Functional fixedness describes why we’re unable to use an object in ways beyond its traditional use. Functional fixedness is a phenomenon found in problem-solving psychology and affects an individual’s ability to innovate and be creative when solving challenges.

Fundamental Attribution Error

Why do we underestimate the influence of the situation on people’s behaviour?

The fundamental attribution error (FAE) describes how, when making judgments about people’s behaviour, we often overemphasise dispositional factors and downplay situational ones. In other words, we believe that people’s personality traits have more influence on their actions, compared to the other factors outside of their control.

Gambler’s Fallacy

Why do we think a random event is more or less likely to occur if it happened several times in the past?

The gambler’s fallacy describes our belief that the probability of a random event occurring in the future is influenced by previous instances of that type of event.

Genetic Fallacy (also known as the fallacy of origins or fallacy of virtue)

Why do we think something is correct based on the source and not the content?

The genetic fallacy describes our propensity to dismiss arguments or information based solely on the source of origin rather than the content; a claim is dismissed or given credibility based on its source rather than the claim itself.

Google Effect

Why do we forget information that we just looked up?

The Google effect, also known as digital amnesia, is the tendency to forget information that is readily available through search engines like Google. We do not commit this information to our memory because we know that this information is easy to access online.

Halo Effect

Why do positive impressions produced in one area positively influence our opinions in another area?

The halo effect is a cognitive bias that claims that positive impressions of people, brands, and products in one area positively influence our feelings in another area.

Hard-easy effect

Why is our confidence disproportionate to the difficulty of a task?

The hard-easy effect, also known as the discriminability effect or the difficulty effect, occurs when we incorrectly predict our ability to complete tasks depending on their level of difficulty. It suggests that we are overly confident in how successful we will be at hard tasks and under-confident about how successful we will be at easy ones.

Heuristics

Why do we take mental shortcuts?

Heuristics are mental shortcuts that can facilitate problem-solving and probability judgments. These strategies are generalizations, or rules-of-thumb, that reduce cognitive load. They can be effective for making immediate judgments, however, they often result in irrational or inaccurate conclusions.

Hindsight Bias

Why do unpredictable events only seem predictable after they occur?

The hindsight bias describes our tendency to look back at an unpredictable event and think it was easily predictable. Also called the “knew-it-all-along” effect, this bias occurs when our current knowledge of an event’s outcome influences our perception of past decisions or judgements, causing us to overestimate our ability to predict future events.

Hot Hand Fallacy

Why do we expect previous success to lead to future success?

The hot hand fallacy is the tendency to believe that someone who has been successful in a task or activity is more likely to be successful again in further attempts. The hot hand fallacy derives from the saying that athletes have “hot hands” when they repeatedly score, causing people to believe that they are on a streak and will continue to have successful outcomes.

Hyperbolic Discounting

Why do we value immediate rewards more than long-term rewards?

Hyperbolic discounting is our inclination to choose immediate rewards over rewards that come later in the future, even when these immediate rewards are smaller.

IKEA Effect

Why do we place disproportionately high value on things we helped to create?

The IKEA effect, named after everyone’s favourite Swedish furniture giant, describes how people tend to value an object more if they make (or assemble) it themselves. More broadly, the IKEA effect speaks to how we tend to like things more if we’ve expended effort to create them.

Identifiable Victim Effect

Why are we more likely to offer help to a specific individual than a vague group?

The identifiable victim effect describes the likelihood that we feel greater empathy, and an urge to help, in situations where tragedies are about a specific, identifiable individual, compared to situations where the victims are a larger, vaguer group of people.

Illusion of Control

Why do we think we have more control over the world than we do?

The illusion of control describes how we believe we have greater control over events than we actually do. Even when something is a matter of random chance, we often feel like we’re able to influence it in some way.

Illusion of Transparency

Why do we feel that others can read our mind?

The illusion of transparency occurs when we overestimate the degree to which other people can perceive our personal thoughts, emotions, and mental states. Individuals experiencing this cognitive bias tend to believe that their internal experiences are more visible to others than they actually are.

Illusion of Validity

Why are we overconfident in our predictions?

The illusion of validity is a cognitive bias that describes our tendency to be overconfident in the accuracy of our judgements, specifically in our interpretations and predictions regarding a given data set.

Illusory Correlation

Why do we think some things are related when they aren’t?

Illusory Correlation is when we see an association between two variables (events, actions, ideas, etc.) when they aren’t actually associated.

Illusory Truth Effect

Why do we believe misinformation more easily when it’s repeated many times?

The illusory truth effect, also known as the illusion of truth, describes how when we hear the same false information repeated again and again, we often come to believe it is true. Troublingly, this even happens when people should know better—that is, when people initially know that the misinformation is false.

Impact Bias

Why do we overestimate our emotional reactions to future events?

The impact bias refers to our tendency to overestimate the intensity and duration of our emotional reactions to future circumstances. This occurs when we incorrectly predict how severely an event will impact our emotional state, imagining a stronger and more lasting emotional impact than we actually experience.

In-group Bias

Why do we treat our in-group better than we do our out-group?

The impact bias refers to our tendency to overestimate the intensity and duration of our emotional reactions to future circumstances. This occurs when we incorrectly predict how severely an event will impact our emotional state, imagining a stronger and more lasting emotional impact than we actually experience.

Incentivisation

Why do we work harder when we are promised a reward?

Incentivisation is attaching a reward to a given behaviour or threatening a penalty for failing to do that behaviour. In some cases, incentives are powerful tools to motivate people to take a certain action. Other times, however, incentives can backfire and might decrease motivation instead of increasing it.

Just-World Hypothesis

Why do we believe that we get what we deserve?

The just-world hypothesis refers to our belief that the world is fair, and consequently, that the moral standings of our actions will determine our outcomes. This viewpoint causes us to believe that those who do good will be rewarded, and those who exhibit negative behaviours will be punished.

Lag Effect

Why does spacing out the repetition of information make one more likely to remember it?

The lag effect suggests that we retain information better when there are longer breaks between repeated presentations of that information.

Law of the Instrument

Why do we use the same skills everywhere?

According to the law of the instrument, when we acquire a new skill, we tend to see opportunities to use it everywhere. This bias is also known as “the law of the hammer”, “the golden hammer”, or “Maslow’s hammer”, in reference to psychologist Abraham Maslow’s famous quote: “I suppose it is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail”.

Less-is-Better Effect

Why do our preferences change depending on whether we judge our options together or separately?

The Less-is-better Effect describes how people sometimes prefer the worse of two options, but only when the options are presented separately. When people consider both their choices together, their preferences reverse, so that the less-is-better effect disappears.

Leveling and Sharpening

Why do we exaggerate some details of a story, but minimize others?

Leveling and sharpening are concepts that have been introduced by early Gestalt psychologists as memory distortions that occurs when we fail to remember details of a certain memory. In psychology, leveling occur when some details are lost or it can also happen when we want to tone down certain moment.

Levels of Processing Effect

Why do we remember information that we attach significance to better than information we repeat?

The levels of processing effect is based on the idea that the way in which information is encoded affects how well it is remembered. The levels of processing model counters the idea that mere repetition helps us retain information long-term. Instead, it suggests that information that is encoded on a deeper level, through meaningful association, is easier to remember.

Look-elsewhere

Effect Why do scientists keep looking for a statistically significant result after failing to find one initially?

The Look-elsewhere Effect describes how, when scientists analyse the results of their experiments, results that are apparently statistically significant might actually have arisen by chance. One reason why this might happen is that a researcher has ignored a statistically insignificant result that they found previously, choosing to “look elsewhere” continuing to search for a significant finding instead of accepting their initial results.

Loss Aversion

Why do we buy insurance?

Loss aversion is a cognitive bias where the emotional impact of a loss is felt more intensely than the joy of an equivalent gain.

Mental Accounting

Why do we think less about some purchases than others?

Mental accounting explains how we tend to assign subjective value to our money, usually in ways that violate basic economic principles. Although money has consistent, objective value, the way we go about spending it is often subject to different rules, depending on how we earned the money, how we intend to use it, and how it makes us feel.

Mere Exposure Effect

Why do we prefer things that we are familiar with?

The mere exposure effect describes our tendency to develop preferences for things simply because we are familiar with them. For this reason, it is also known as the familiarity principle.

Messenger Effect

Why do we find some people more credible than others?

The messenger effect is a cognitive bias that causes us to judge the validity or relevance of information based on its source. Instead of objectively analysing the message’s content, our opinions of the person delivering the information affect our interpretation.

Motivating Uncertainty

Effect Why are we more motivated by rewards of unknown sizes?

We often find ourselves to be more motivated by rewards of unknown magnitudes than by known rewards because the uncertainty makes it feel like a game. However, this effect, which is known as the motivating uncertainty effect, only occurs when we focus on the journey towards the reward and not when we focus on actually winning the reward.

Naive Allocation

Why do we prefer to spread limited resources across our options?

Naive allocation, otherwise known as naive diversification, or the diversification bias, refers to our tendency to equally divide our resources among the options available to us, regardless of whether the options themselves can be considered equal.

Naive Realism

Why do we believe we have an objective understanding of the world?

Naive realism is the tendency to believe our perception of the world reflects it exactly as it is, unbiased and unfiltered. We don’t think our emotions, past experiences, or cultural identity affect the way we perceive the world and thus believe others see it in the same way as we do. Naive realism rests on the idea that there is a material, objective world accessible to us and others around us.

Naive realism is within the egocentric bias category, a group of biases that indicate we rely too heavily on our own point of view and fail to understand that it is a personal point of view. These biases make it difficult for us to understand other people’s perspectives and can lead to arguments and polarisation.

Negativity Bias

Why is the news always so depressing?

The negativity bias is a cognitive bias that results in adverse events having a more significant impact on our psychological state than positive events. Negativity bias occurs even when adverse events and positive events are of the same magnitude, meaning we feel negative events more intensely.

Noble Edge Effect

Why do we tend to favour brands that show care for societal issues?

When companies demonstrate social responsibility that is perceived as genuine by consumers, they are rewarded with increased respect, which in turn leads to greater profits. That’s the noble edge effect.

Normalcy Bias

Why do we believe that nothing bad is going to happen?

The normalcy bias describes our tendency to underestimate the possibility of disaster and believe that life will continue as normal, even in the face of significant threats or crises.

Nostalgia Effect

How do our sentimental feelings for the past influence our actions in the present?

Feelings of nostalgia, or sentimentality for days gone by, lead us to place increased value on social connectedness and less value on saving money. Nostalgia’s influence over our willingness to spend money is referred to as the nostalgia effect.

Observer Expectancy

Effect Why do we change our behaviour when we’re being watched?

The observer expectancy effect, also known as the experimenter expectancy effect, refers to how the perceived expectations of an observer can influence the people being observed. This term is usually used in the context of research, to describe how the presence of a researcher can influence the behaviour of participants in their study.

Omission Bias

Why don’t we pull the trolley lever?

The omission bias refers to our tendency to judge harmful actions as worse than harmful inactions, even if they result in similar consequences.

Optimism Bias

Why do we overestimate the probability of success?

The optimism bias refers to our tendency to overestimate our likelihood of experiencing positive events and underestimate our likelihood of experiencing negative events.

Ostrich Effect

Why do we prefer to ignore negative information?

The ostrich effect, also known as the ostrich problem, is a cognitive bias that describes how people often avoid negative information, including feedback that could help them monitor their goal progress. Instead of dealing with the situation, we bury our heads in the sand, like ostriches. This avoidance can often make things worse, incurring costs that we might not have had to pay if we had faced things head-on.

Overjustification Effect

Why do we lose interest in an activity after we are rewarded for it?

The overjustification effect describes our tendency to become less intrinsically motivated to partake in an activity that we used to enjoy when offered an external incentive such as money or a reward.

Peak-end Rule

How do our memories differ from our experiences?

The peak-end rule is a psychological heuristic that changes the way we recall past events. We remember a memory or judge an experience based on how they felt at the peak moments, as well as how they felt at the end.

Pessimism bias

Why do we think we’re destined to fail?

The pessimism bias refers to the tendency to overestimate the likelihood of negative events while underestimating the likelihood of positive events. This attitude of expecting the worst is a prominent cognitive feature of depression and can have considerable ramifications on both a personal and societal level.

Planning Fallacy

Why do we underestimate how long it will take to complete a task?

The planning fallacy describes our tendency to underestimate the amount of time it will take to complete a task, as well as the costs and risks associated with that task, even if it contradicts our experiences.

Pluralistic Ignorance

Why do we think our beliefs are different from the majority?

Pluralistic ignorance is when we believe that our private views are different from those of the majority. This often leads them to suppress their own beliefs and behaviours to conform to what they perceive as the societal norm.

Primacy Effect

Why do we only remember the first things on our grocery list?

The primacy effect is the tendency to remember the first piece of information we encounter better than information presented later on.

Priming

Why do some ideas prompt other ideas later on without our conscious awareness?

Priming, or, the priming effect, occurs when an individual’s exposure to a certain stimulus influences their response to a subsequent prompt, without any awareness of the connection. These stimuli are often related to words or images that people see during their day-to-day lives.

Projection Bias

Why do we think our current preferences will remain the same in the future?

The projection bias is a self-forecasting error where we overestimate how much our future selves will share the same beliefs, values and behaviours as our current selves, causing us to make short-sighted decisions.

Reactive devaluation

Why is negotiation so difficult?

Reactive devaluation refers to our tendency to disparage proposals made by another party, especially if this party is viewed as negative or antagonistic. This cognitive bias can serve as a major barrier in negotiations.

Recency Effect

Why do we better remember items at the end of a list?

The recency effect refers to our tendency to better remember and recall information presented to us most recently, compared to information we encountered earlier. The recency effect is one of two memory recall biases that make up the serial position effect, a phenomenon which describes how the location of an item in a sequence can impact its memorability.

Regret Aversion

Why do we anticipate regret before we make a decision?

Regret aversion occurs when a decision is made to avoid regretting an alternative decision in the future. Regret can be a powerless and discomforting state and people sometimes make decisions in order to avoid this outcome.

Representativeness Heuristic

Why do we use similarity to gauge statistical probability?

The representativeness heuristic is a mental shortcut that we use when estimating probabilities. When we’re trying to assess how likely a certain event is, we often make our decision by assessing how similar it is to an existing mental prototype.

Response Bias

Why do we give false survey responses?

The response bias refers to our tendency to provide inaccurate, or even false, answers to self-report questions, such as those asked on surveys or in structured interviews.

Restraint Bias

Why do we overestimate our self-control?

The restraint bias refers to our tendency to overestimate the level of control we have over our impulsive behaviours. These urges typically come from “visceral impulses” such as hunger, drug cravings, fatigue, or sexual arousal.

Rosy Retrospection

Why do we think the good old days were so good?

Rosy retrospection refers to our tendency to recall the past more fondly than the present, all else being equal. It is a cognitive bias that runs parallel with the concept of nostalgia, though the latter does not always directly imply a biased recollection. The phrase stems from the English idiom, “rose-tinted glasses,” where people see things as better than they were.

Salience Bias

Why do we focus on items or information that are more prominent and ignore those that are not?

The salience bias describes our tendency to focus on items or information that are more noteworthy while ignoring those that do not grab our attention.

Self-serving Bias

Why do we blame external factors for our own mistakes?

The self-serving bias, or self-attribution bias, describes our tendency to attribute positive outcomes and successes to internal factors like our personal traits, skills, or actions but attribute negative results or failures to external factors, shifting the blame to situational factors beyond our control, such as bad luck or the actions of others.

Serial Position Effect

Why do we better remember items at the beginning or end of a list?

The serial position effect describes how our memory is affected by the position of information in a sequence. It suggests that we best remember the first and last items in a series and find it hard to remember the middle items.

Sexual Over perception Bias

Why do men think that women are always flirting with them?

The sexual over perception bias relates to the tendency to overperceive another individual’s sexual interest in oneself. The bias predominantly occurs in men, where they are more likely to overestimate a woman’s sexual interest while women are more likely to underestimate a man.

Social Norms

Why do we follow the behaviour of others?

Social norms are collectively held beliefs about what kind of behaviour is appropriate in a given situation. They range from specific customs—for example, the Western custom of shaking hands with somebody when you meet them for the first time to more general rules that govern behaviour and influence our understanding of other people.

Source Confusion

Why do we forget where our memories come from?

Source confusion, also known as source misattribution or unconscious transference, is a type of memory error. It occurs when someone does not remember where certain memories come from.

Spacing Effect

Why do we retain information better when we learn it over a long time period?

The spacing effect demonstrates that learning is more effective when repeated in spaced-out sessions. By repeating and spacing out information individuals learn, they can better recall that information in the future.

Spotlight Effect

Why do we feel like we stand out more than we really do?

The spotlight effect describes how people tend to believe that others are paying more attention to them than they actually are, in other words, our tendency to always feel like we are “in the spotlight.” This bias shows up frequently in our day-to-day lives, both in positive situations (like when we nail a presentation, and overestimate how impressed all our co-workers must be) and in negative ones (like when we bomb the presentation and feel like everybody must be laughing about it behind our backs).

Status Quo Bias

Why do we tend to leave things as they are?

The status quo bias describes our preference for the current state of affairs, resulting in resistance to change.

Suggestibility

Why is yawning contagious?

Suggestibility refers to how susceptible we are to altering our behaviour based on the suggestions of others.

Survivorship Bias

Why do we misjudge groups by only looking at specific group members?

Survivorship bias is a cognitive shortcut that occurs when a successful subgroup is mistaken as the entire group, due to the invisibility of the failure subgroup. The bias’ name comes from the error an individual makes when a data set only considers the “surviving” observations, excluding points that didn’t survive.

Take-the-best Heuristic

Why do we focus on one characteristic to compare when choosing between alternatives?

The take-the-best heuristic is a shortcut we use when making decisions between alternatives, so that we can quickly make decisions without having to know all the information about each alternative.

When we employ the take-the-best heuristic, we decide based on only one cue or characteristic which we think differentiates the options. Instead of considering all the reasons why we might choose one alternative over the other, we pick one reason and base our decision solely on that reason.

Telescoping Effect

Why do some things “seem like they just happened yesterday?”

The telescoping effect refers to inaccurate perceptions regarding time, where people see recent events as more remote than they are (backward telescoping), and remote events as more recent (forward telescoping). This mental error in memory can occur whenever we make temporal assumptions regarding past events.

The Illusion of Explanatory Depth

Why do we think we understand the world more than we actually do?

The illusion of explanatory depth (IOED) describes our belief that we understand more about the world than we actually do. It is often not until we are asked to actually explain a concept that we come face to face with our limited understanding of it.

The Pygmalion effect

Why do we perform better when someone has high expectations of us?

The Pygmalion effect describes situations where someone’s high expectations improve our behaviour and therefore our performance in a given area. It suggests that we do better when more is expected of us.

The Sunk Cost Fallacy

Why are we likely to continue with an investment even if it would be rational to give it up?

The sunk cost fallacy is our tendency to follow through with something that we’ve already invested heavily in (be it time, money, effort, or emotional energy), even when giving up is clearly a better idea.

Zero Risk Bias

Why do we seek certainty in risky situations?

Zero risk bias relates to our preference for absolute certainty. We tend to opt for situations where we can completely eliminate risk, seeking solace in the figure of 0%, over alternatives that may actually offer greater risk reduction.

Further thought

The relation between cognitive bias, habit and social convention is an important issue.

People do appear to have individual differences in their susceptibility to decision biases including overconfidence, temporal discounting, and bias blind spot. It should also be noted that levels of bias within individuals are possible to change.

There are some, notably Gerd Gigerenzer, who believe cognitive biases are not biases, but rules of thumb, or as he puts it “gut feelings” that can actually help us make accurate decisions in our lives, arguing biases are primarily defects of human cognition or the result of behavioural patterns that are actually adaptive or “ecologically rational”.

Central to that argument is how one defines ‘rationality’ and ‘bias’. A case can be made for anything if you change or re-define words to suit a narrative.

Vaccination & Vaccine (2021)

Before the change, the definition for ‘vaccination’ from America’s CDC read, “the act of introducing a vaccine into the body to produce immunity to a specific disease.” Now, the word ‘immunity’ has been switched to ‘protection.’
The term “vaccine” also got a makeover. The CDC’s definition changed from “a product that stimulates a person’s immune system to produce immunity to a specific disease” to the current “a preparation that is used to stimulate the body’s immune response against diseases.”

Merriam-Webster removed the immunity part of its ‘vaccine’ definition.
Merriam-Webster, the company known for its reference books and dictionaries, has changed its definition of Vaccine.
“Vaccine used to be defined as a substance that provides ‘immunity’ to a specific disease,”
“Now, Merriam Webster has literally changed the definition of ‘vaccine’, removing ‘immunity’ with ‘immune response’.