The probabilities of unique events.

Autor: Sangeet S Khemlani, Max Lotstein, Phil Johnson-Laird
Jazyk: angličtina
Rok vydání: 2012
Předmět:
Zdroj: PLoS ONE, Vol 7, Iss 10, p e45975 (2012)
Druh dokumentu: article
ISSN: 1932-6203
DOI: 10.1371/journal.pone.0045975
Popis: Many theorists argue that the probabilities of unique events, even real possibilities such as President Obama's re-election, are meaningless. As a consequence, psychologists have seldom investigated them. We propose a new theory (implemented in a computer program) in which such estimates depend on an intuitive non-numerical system capable only of simple procedures, and a deliberative system that maps intuitions into numbers. The theory predicts that estimates of the probabilities of conjunctions should often tend to split the difference between the probabilities of the two conjuncts. We report two experiments showing that individuals commit such violations of the probability calculus, and corroborating other predictions of the theory, e.g., individuals err in the same way even when they make non-numerical verbal estimates, such as that an event is highly improbable.
Databáze: Directory of Open Access Journals