confirmation bias: a standalone construct

Peter Wason first demonstrated the tendency experimentally in his 1960 study On the failure to eliminate hypotheses in a conceptual task, where he gave people the number triple 2-4-6, asked them to discover the rule that generated it, and let them test any triples they liked. Most sought triples that fit the rule they already suspected rather than ones that might break it, and so settled on wrong rules, an example of seeking confirming rather than disconfirming evidence. Raymond Nickerson's 1998 review Confirmation bias: A ubiquitous phenomenon in many guises gathered the scattered findings under one name and defined the bias as the seeking or interpreting of evidence in ways that are partial to beliefs, expectations, or a hypothesis already held. As a landmark construct it spans the full cycle of belief maintenance: it covers how people search for information, how they weigh and remember what they find, and how they read ambiguous evidence, and it has been documented across everyday reasoning, science, medicine, law, and politics, which is why it recurs so widely in the study of human judgement.[1][2]

Unit

A directional bias in hypothesis testing and evidence evaluation, observed in an individual reasoner

Recovery means

Not applicable

Measured by

Identified experimentally through tasks such as Wason's 2-4-6 rule-discovery task and hypothesis-testing paradigms, and through coding of how people select, weight, and interpret confirming versus disconfirming information