Reviewed claims link to primary studies or high-quality reviews instead of relying on an uncited summary.
Evidence layer
Check the claim, not just the label.
43 of 216 canonical entries currently include an editorial evidence review. Each review separates the quick definition from what the research actually supports, where the effect has limits, and which sources were checked.
How this works
Evidence class is a reading aid, not a truth score.
Boundary conditions, measurement disputes, and terminology problems stay visible instead of being flattened into a confident definition.
Every review carries an editorial review date so future research can trigger a re-check rather than silently aging in place.
Controlled evidence classes
Six broad classes. Entry-specific status stays descriptive.
The class makes the broad evidence situation scannable. It does not replace the descriptive status or boundary conditions on the individual review.
Established19
Replicated or broad evidence supports the core pattern, while ordinary boundary conditions and mechanism debates may still remain.
Supported14Credible evidence supports the pattern, but the scope is narrower, the literature is smaller, or important boundary conditions deserve emphasis.
Mixed4Evidence supports some versions of the claim while important measurement, magnitude, mechanism, or interpretation disputes remain.
Contested1The named claim or its popular causal interpretation faces substantial unresolved challenge, alternative explanations, or conflicting evidence.
Domain-specific4Evidence is concentrated in a narrow task, research program, or application domain and should not be generalized as a universal cognitive law.
Reviewed concept1A useful reviewed term, measurement concept, or broader construct that is not one standalone cognitive-bias mechanism.
Reviewed entries
43 entries with a source-grounded evidence layer.
Moral Luck – when outcomes change blame for otherwise similar choices
Resultant moral luck describes cases where judgments of blame, punishment, or moral evaluation differ because otherwise similar actions lead to different outcomes partly outside the agent's control. Outcome information does affec…
3 reviewed sourcesRead evidence review
Anthropomorphism – when nonhuman systems are read as humanlike
Anthropomorphism is the attribution of humanlike properties, intentions, emotions, or mental states to nonhuman agents. It is a well-established psychological phenomenon, but it is not automatically a cognitive error: humanlike m…
4 reviewed sourcesRead evidence review
Conservatism Bias – when a probability estimate changes too little
Here, conservatism means under-updating: new evidence changes a probability judgment less than a Bayesian benchmark would predict. It should not be confused with the separate memory phenomenon in this corpus that pulls remembered…
2 reviewed sourcesRead evidence review
Anchoring Effect – when a starting number pulls later estimates toward it
Anchoring is a well-supported effect in which an initial numerical value can pull a later estimate toward it. A 2026 meta-analysis covering 2,601 effect sizes found a large overall effect, but also substantial variation across st…
4 reviewed sourcesRead evidence review
Confirmation Bias – when a belief shapes how evidence is searched and judged
Confirmation bias is an umbrella label for several ways existing beliefs or hypotheses can influence information search and interpretation. It should not be reduced to one behaviour such as reading only agreeable news, and a pref…
2 reviewed sourcesRead evidence review
Curse of Knowledge – when what you know distorts what you expect others to know
Knowing more can make it harder to estimate what a less-informed person knows or understands, but the size and mechanism of the effect depend on the task. The useful claim is not that experts are unable to teach beginners; it is…
3 reviewed sourcesRead evidence review
Declinism – when the present is judged against an idealized past
Declinism is best treated here as an umbrella label for judging the present as worse than an idealized past, not as one standardized cognitive-bias construct with a single mechanism. Research directly supports several narrower in…
3 reviewed sourcesRead evidence review
Hindsight Bias – when knowing the outcome changes what seemed predictable
Knowing an outcome can make the outcome look more predictable in retrospect. The effect has been studied for decades and across many settings, but it does not mean that every confident explanation after an event is biased.
2 reviewed sourcesRead evidence review
Hungry Judge Effect – a famous parole-board finding with an uncertain cause
The famous 2011 parole-board study found favorable decisions were more common early in a decision session and immediately after food breaks. It did not directly measure hunger, glucose, fatigue, or mood, and the authors explicitl…
3 reviewed sourcesRead evidence review
Impact Bias – when forecasts overstate future emotional reactions
People often overestimate how intense or long their emotional reactions to future events will be, especially when the focal event crowds out everything else that will also shape daily experience. The literature is broader than a…
4 reviewed sourcesRead evidence review
Mere Urgency Effect – when ‘urgent’ steals the day from ‘important’
Zhu, Yang and Hsee (2018) reported five experiments in which people sometimes chose objectively lower-payoff tasks when those tasks had short, spurious completion windows, even after several ordinary reasons for prioritizing urge…
2 reviewed sourcesRead evidence review
Outcome Bias – when results change the evaluation of a decision
Outcome bias occurs when knowledge of a result changes how people evaluate the quality of a decision even when the information available at the time of the decision is held constant. Outcomes can still be relevant for learning, s…
2 reviewed sourcesRead evidence review
Prevention Bias – favoring preventive security controls over detection and response
Prevention Bias is a label introduced in experimental research on information-security investment. In that task, participants favored preventive controls over detection-and-response controls even when the experiment was designed…
2 reviewed sourcesRead evidence review
Projection Bias – when current preferences shape forecasts of future preferences
Projection bias describes a tendency to overproject current tastes or visceral states onto future preferences. People often understand that tastes will change but underestimate how much they will change. The construct is most dir…
3 reviewed sourcesRead evidence review
Sunk Cost Effect – when past costs influence the next choice
The sunk cost effect is a documented tendency for irrecoverable prior investments of money, time, or effort to influence later choices. A meta-analytic review found clear evidence for the effect overall, while also showing that i…
3 reviewed sourcesRead evidence review
Surrogation – when a performance measure starts replacing the goal
Surrogation is a domain-specific management-accounting construct: a measure that was designed to represent a strategic objective can start to be treated as though it were the objective itself. It is closely related to metric fixa…
2 reviewed sourcesRead evidence review
Systematic Bias – a measurement and statistical concept, not one cognitive bias
Systematic bias is a general statistical and measurement concept: a non-random tendency for measurements, estimates, or study results to deviate from a reference or target value in a consistent or predictable way. Standards in me…
3 reviewed sourcesRead evidence review
Unit Bias – when one unit quietly becomes the ‘right’ amount
The original unit-bias paper reported experiments in which changing the size of a food unit or serving tool changed how much people selected or consumed even when they could take as many units as they wanted. Later work by Geier…
2 reviewed sourcesRead evidence review
Value Selection Bias – choosing supplied numbers instead of constructing the Bayesian answer
Value Selection Bias is a narrow reasoning pattern reported in Bayesian diagnostic problems: when participants did not derive the correct solution, incorrect answers were strongly drawn toward numerical values already present in…
2 reviewed sourcesRead evidence review
Backfire Effect – when a correction can strengthen a false belief
Corrections usually improve factual accuracy. A true backfire effect, where a correction makes the targeted false belief stronger, appears to be uncommon and sensitive to context and measurement. It should not be treated as the d…
3 reviewed sourcesRead evidence review
Congruence Bias – when the test fits one hypothesis but does not separate alternatives
Congruence Bias is a narrower hypothesis-testing pattern than the broad umbrella of confirmation bias. In classic work, people overvalued tests that were likely to return a positive result if their leading hypothesis were true, e…
2 reviewed sourcesRead evidence review
Planning Fallacy – when plans make completion times look too optimistic
The planning fallacy is a well-documented tendency for people to predict their own task completion times too optimistically. The effect has been observed across different kinds of tasks, but it is not a rule that every plan will…
4 reviewed sourcesRead evidence review
Restraint Bias – when calm us overestimates future self-control
Nordgren and colleagues reported four studies in which stronger beliefs about impulse control were linked to greater exposure to temptation and, in a study of recovering smokers, higher later relapse through increased exposure. T…
2 reviewed sourcesRead evidence review
Less-Is-Better Effect – when less looks better because the comparison is missing
Hsee (1998) reported less-is-better patterns across gift generosity, ice-cream valuation and dinnerware valuation when options were evaluated separately. A 2023 preregistered close replication and extension with 400 analyzed part…
2 reviewed sourcesRead evidence review
Automation Bias – when automated advice replaces independent checking
Automation bias is a documented pattern of inappropriate reliance on automated cues or recommendations. It can produce commission errors when a user follows incorrect advice and omission errors when a user fails to act because au…
4 reviewed sourcesRead evidence review
Framing Effect – when equivalent descriptions lead to different choices
Framing research covers several distinct paradigms. Risky-choice framing, where equivalent outcomes are presented as gains or losses, is a well-established effect with substantial evidence across many studies. A classic meta-anal…
5 reviewed sourcesRead evidence review
Decoy Effect – when an inferior option changes the comparison between better options
The decoy effect is a well-documented family of context effects in which adding an inferior or otherwise strategically positioned alternative can change choice shares among the original options. The classic attraction effect uses…
4 reviewed sourcesRead evidence review
Default Effect – when a pre-selected option changes what people choose
Pre-selecting an option often increases the chance that people choose it, but the size of the default effect varies greatly across domains and designs. A 2019 meta-analysis of 58 studies found a substantial average effect togethe…
4 reviewed sourcesRead evidence review
Denomination Effect – when the shape of money changes our willingness to spend it
Raghubir and Srivastava reported field and laboratory studies showing lower spending likelihood when the same amount of money was held as one larger denomination rather than several smaller denominations. Later work by Raghubir,…
2 reviewed sourcesRead evidence review
Distinction Bias – when comparison makes small differences look important
Hsee and Zhang introduced distinction bias to describe cases where joint evaluation makes quantitative differences between options seem more important than those differences are during single evaluation or experience. A 2021 clos…
2 reviewed sourcesRead evidence review
Availability Heuristic – when easy-to-recall examples shape frequency judgments
Availability is a judgment heuristic: people can use how easily examples or scenarios come to mind when estimating frequency or probability. That shortcut is not automatically an error because memorable or accessible examples can…
3 reviewed sourcesRead evidence review
Appearance–Capability Expectation – when a robot’s design changes what you expect it can do
Research supports the broader pattern that a robot's appearance, morphology, framing, and human-likeness shape expectations about its competence, social qualities, and likely behavior. However, 'Form-Function Attribution Bias' is…
4 reviewed sourcesRead evidence review
Escalation of Commitment – when setbacks lead to more investment in the same course
Sunk-cost effects and escalation of commitment overlap but are not interchangeable. Sunk-cost research asks whether irrecoverable prior investments influence current choices. Escalation of commitment describes persistence or addi…
3 reviewed sourcesRead evidence review
Zero-Sum Bias – when we see competition where gains can coexist
Meegan introduced zero-sum bias in three university-grading experiments where grades were based on an absolute standard and high grades were not rationed. Participants were nevertheless more likely to predict a low next grade aft…
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Continued Influence Effect – when corrected information still shapes reasoning
The continued influence effect describes a specific pattern: false or outdated information can keep affecting later reasoning even after a clear correction. It does not mean the correction had no effect, that the person rejected…
5 reviewed sourcesRead evidence review
Fading Affect Bias – when negative emotional intensity tends to fade faster
Fading Affect Bias describes an average asymmetry in autobiographical memory: affect linked to negative events tends to weaken faster over time than affect linked to positive events. It is a group-level pattern with important mod…
2 reviewed sourcesRead evidence review
Rosy Retrospection – when a past experience is remembered more positively
Rosy Retrospection describes a pattern in which later evaluations of a past experience can become more positive than evaluations recorded during the experience itself. The classic work studied specific meaningful events and found…
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Subadditivity Effect – when unpacking changes probability estimates
People often give a larger total probability when an event is unpacked into separate possibilities than when the same event is judged as one packed category. The effect is not universal: how the possibilities are described and ho…
3 reviewed sourcesRead evidence review
Loss Aversion – when a loss can carry more weight than an equivalent gain
Loss aversion is a central component of prospect theory and many studies estimate losses as receiving greater subjective weight than gains around a reference point. However, the effect should not be summarized with one universal…
4 reviewed sourcesRead evidence review
Status Quo Bias – when the current option gets extra weight because it is already in place
Status quo bias describes extra preference for an option because it is the current or existing state. Classic experiments and field observations found disproportionate persistence with status quo options, but keeping the current…
3 reviewed sourcesRead evidence review
Dunning–Kruger Effect – when performance and self-assessment do not line up
The original studies found substantial overestimation among low performers in specific tasks, but the popular story that incompetent people are simply very confident while experts systematically underestimate themselves is too br…
3 reviewed sourcesRead evidence review
Hot–Cold Empathy Gap – when one state is a poor guide to choices in another
The hot–cold empathy gap describes difficulty predicting preferences, behavior, or experience across different visceral or affective states. In a relatively cold state, people can underappreciate how pain, hunger, sexual arousal,…
3 reviewed sourcesRead evidence review
Illusory Truth Effect – when repetition makes a claim feel more true
Repeated claims receive higher truth ratings than comparable new claims on average, but the effect is heterogeneous and does not generalize equally to every kind of statement. A 2026 systematic review and meta-analysis covering 1…
6 reviewed sourcesRead evidence review