Code repository for 'Clarifying the role of an unavailable distractor in human multiattribute choice' (eLife)

Yinan Cao¹ & Konstantinos Tsetsos^1,2
[1] Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
[2] School of Psychological Science, University of Bristol, Bristol, United Kingdom

Abstract

Decisions between two economic goods can be swayed by a third unavailable 'decoy' alternative, which does not compete for choice, notoriously violating the principles of rational choice theory. Although decoy effects typically depend on the decoy's position in a multiattribute choice space, recent studies using risky prospects (i.e., varying in reward and probability) reported a novel 'positive' decoy effect operating on a single 'value' dimension: the higher the 'expected value' of an unavailable (distractor) prospect was, the easier the discrimination between two available target prospects became, especially when their expected-value difference was small. Here we show that this unidimensional distractor effect affords alternative interpretations: it occurred because the distractor's expected value covaried positively with the subjective utility difference between the two targets. Looking beyond this covariation, we report a modest 'negative' distractor effect operating on subjective utility, as well as classic multiattribute decoy effects. A normatively meaningful model (selective integration), in which subjective utilities are shaped by 'intra-attribute' information distortion, reproduces the multiattribute decoy effects, and as an epiphenomenon, the negative unidimensional distractor effect. These findings clarify the modulatory role of an unavailable distracting option, shedding fresh light on the mechanisms that govern multiattribute decisions.

Notes

• To run model fitting or comparison, unzip "VBA-toolbox-master.zip" in ./functions/
• Or install the VBAtoolbox yourself: https://github.com/MBB-team/VBA-toolbox

Preprint

https://www.biorxiv.org/content/10.1101/2022.08.03.502693v3

eLife paper

https://elifesciences.org/articles/83316

• This manuscript underwent the review process prior to the implementation of eLife's updated evaluation model.

How to cite this work

APA:
Cao, Y., & Tsetsos, K. (2022). Clarifying the role of an unavailable distractor in human multiattribute choice. eLife, 11, e83316.
BibTeX: https://github.com/YinanCao/multiattribute-distractor/blob/main/83316.bib

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License

https://github.com/YinanCao/multiattribute-distractor/blob/main/LICENSE.md