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Title: A Pragmatic Account of the Weak Evidence Effect
Abstract

Language is not only used to transmit neutral information; we often seek to persuade by arguing in favor of a particular view. Persuasion raises a number of challenges for classical accounts of belief updating, as information cannot be taken at face value. How should listeners account for a speaker’s “hidden agenda” when incorporating new information? Here, we extend recent probabilistic models of recursive social reasoning to allow for persuasive goals and show that our model provides a pragmatic account for why weakly favorable arguments may backfire, a phenomenon known as the weak evidence effect. Critically, this model predicts a systematic relationship between belief updates and expectations about the information source: weak evidence should only backfire when speakers are expected to act under persuasive goals and prefer the strongest evidence. We introduce a simple experimental paradigm called the Stick Contest to measure the extent to which the weak evidence effect depends on speaker expectations, and show that a pragmatic listener model accounts for the empirical data better than alternative models. Our findings suggest further avenues for rational models of social reasoning to illuminate classical decision-making phenomena.

 
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NSF-PAR ID:
10372508
Author(s) / Creator(s):
; ;
Publisher / Repository:
DOI PREFIX: 10.1162
Date Published:
Journal Name:
Open Mind
Volume:
6
ISSN:
2470-2986
Page Range / eLocation ID:
p. 169-182
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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