{"pk":29825,"title":"Configurative Weighting as a Two-Plane Approximation of Bayesian Estimates","subtitle":null,"abstract":"Configurative weighting and adding can be a surprisingly effective approximation of multiplicative functions. In thecontext of joint probability judgment, Nilsson et al. (2009) has shown that, when marginal probabilities are only approxi-mately known, the configurative weighted average (CWA) of two probabilities not only predicts a high level of conjunctionfallacies, as observed in data, but also correlates higher with the true joint probability than if the two probabilities are mul-tiplied. Here we show that [1] the surface representing the optimal Bayesian estimate of a joint probability can be closelyapproximated by two planes, [2] configurative weighting and adding, such as the CWA model, constitutes such a two-planeapproximation, and [3] a bias-variance tradeoff is not sufficient to explain the accuracy of the CWA. More generally, thissuggests that the efficiency of heuristics might be due to suitable weighting operations rather than less-is-more effects.","language":"eng","license":{"name":"","short_name":"","text":null,"url":""},"keywords":[],"section":"Poster Session 2","is_remote":true,"remote_url":"https://escholarship.org/uc/item/8tr4d934","frozenauthors":[{"first_name":"Joakim","middle_name":"","last_name":"Sundh","name_suffix":"","institution":"University of Warwick","department":""},{"first_name":"Jerker","middle_name":"","last_name":"Denrell","name_suffix":"","institution":"University of Warwick","department":""}],"date_submitted":null,"date_accepted":null,"date_published":"2020-01-01T10:00:00-08:00","render_galley":null,"galleys":[{"label":"PDF","type":"pdf","path":"https://journalpub.escholarship.org/cognitivesciencesociety/article/29825/galley/19679/download/"}]}