01Member
Decision Making
Action Bias
A preference for doing something when action is not clearly better than waiting or doing nothing.
Behavioural psychology library
Understand the behaviour. Then question the pattern.
Search in the language of the product problem. Each ingredient explains what may be happening, where the evidence applies, and what to protect when you design with it.
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105 live ingredients
02Member
Perception & Cognition
Affect Heuristic
A readily available positive or negative feeling can become a shortcut for judging an option’s risk, benefit or overall value.
03Member
Decision Making
Ambiguity Effect
When outcome probabilities are unclear, some people prefer a comparable option with known probabilities—but not in every context.
04Free
Decision Making
Anchoring Bias
An earlier number can pull a later estimate towards it, especially when the answer is uncertain.
05Member
Usability & Interaction
Anticipated Regret (Regret Aversion)
A person may consider how they would feel if a chosen outcome proved worse than a foregone alternative, but anticipated regret can favour action, inaction, risk or safety depending on feedback and context.
06Member
Usability & Interaction
Attentional Bias
Attention can be allocated differently to threat or personally relevant cues, particularly in anxiety—but the pattern depends on the person, task and timing.
07Member
Social & Emotional Influence
Authority Bias
Perceived legitimate expertise or institutional authority can receive more weight than the supporting reasons warrant.
08Member
Usability & Interaction
Availability Heuristic
When estimating how common or likely something is, people may substitute how readily relevant examples come to mind.
09Member
Usability & Interaction
Backfire Effect
A correction makes belief in the false claim stronger than it would have been without the correction—a possible but uncommon result.
10Member
Social & Emotional Influence
Bandwagon Effect (popularity influence)
Knowing that many other people chose or support an option can change demand or judgement, even when popularity is not evidence that the option fits this person.
11Member
Social & Emotional Influence
Barnum Effect
Broad, high-base-rate statements can feel uniquely accurate when they are presented as a personal assessment.
12Member
Usability & Interaction
Base Rate Fallacy
A vivid case-specific clue can receive too much weight, or the relevant starting frequency too little, when people estimate how likely an outcome is.
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