Reasoning Biases Vocabulary

ignoring general prevalence when evaluating specific probabilities

“Base rate neglect: assuming a positive test means disease, ignoring that most people are healthy.”

Origin: Latin basis `foundation` + neglectus `disregarded`

judging a combination of events as more likely than a single event

“The conjunction fallacy: thinking 'bank teller and feminist' is more likely than just 'bank teller.'”

Origin: Latin coniungere `to join together` + fallacia `deception`

judging probability by similarity to a prototype

“The representativeness heuristic makes people think coin flips should 'look random.'”

Origin: Latin repraesentare `to present again` + Greek heuristikos `inventive`

preferring complete elimination of risk over greater overall reduction

“Zero-risk bias: choosing to eliminate one small risk entirely over reducing a bigger one.”

Origin: Arabic sifr `empty, zero` + Latin risicum `danger`

underestimating the likelihood and impact of disasters

“Normalcy bias kept residents from evacuating despite clear warnings.”

Origin: Latin normalis `made according to rule` + bias

focusing on successes while overlooking failures

“Survivorship bias: studying only successful entrepreneurs, ignoring the many who failed.”

Origin: Latin supervivere `to outlive` + bias from Old French biais

seeing patterns in random data

“The clustering illusion makes people find 'hot streaks' in random basketball shots.”

Origin: Old English clyster `cluster` + Latin illusio `mockery`

judging a decision by its result rather than by the quality of the decision

“Outcome bias: praising a risky bet that paid off despite it being statistically foolish.”

Origin: Middle English out `out` + come + bias

distortion from non-random sample selection

“Surveying only mall shoppers introduces selection bias about consumer behavior.”

Origin: Latin selectio `a choosing` + bias

maintaining beliefs despite contradictory evidence

“Even after the study was retracted, belief perseverance kept the myth alive.”

Origin: Latin perseverantia `steadfastness` from perseverare `persist`