ABSTRACT

Choices in value-based decision making are affected by the magnitude of the alternatives (i.e. the summed values of the options). Magnitude sensitivity has been instrumental in discriminating between computational models of choice. Smith and Krajbich [(2019a). Gaze amplifies value in decision making. Psychological Science, 30(1), 116–128. https://doi.org/10.1177/0956797618810521] have shown that the attentional drift-diffusion model (aDDM) can account for magnitude sensitivity. This is because the discount parameter on the value of the nonfixated alternative ensures faster choices for high-magnitude alternatives, even in the case of high-magnitude equal alternatives compared to low-magnitude equal alternatives. Their result highlights the importance of visual fixations as a mechanism for magnitude sensitivity. This rationale relies on the untested assumption that the discount parameter is constant across magnitude levels. However, the discount parameter could vary as a function of the magnitude of the alternatives in unpredicted ways; this would suggest that the ability of the aDDM to account for magnitude sensitivity has been misinterpreted by previous research. Here, we reanalyse previous datasets and we directly test whether attentional discounting scales with the magnitude of the alternatives. Our analyses show that attentional discounting does not vary with magnitude. This result further strengthens the aDDM and the role that visual fixations could play as an explanation of magnitude sensitivity.

摘要

基于价值的决策中的选择会受到备选方案的大小（即，期权总和）的影响。幅值灵敏度有助于区分选择的计算模型。Smith and Krajbich [（2019a）。凝视会放大决策制定的价值。心理科学，30（1），116-128。https://doi.org/10.1177/0956797618810521]已显示注意漂移扩散模型（aDDM）可以说明幅度敏感度。这是因为相对于低幅值等价替代品，非固定替代品价值的折扣参数确保了对高幅值替代品的更快选择，即使在高幅值等价替代品的情况下也是如此。他们的结果突出了视觉注视作为幅度敏感度机制的重要性。该原理基于未经检验的假设，即折扣参数在幅度级别上是恒定的。但是，折扣参数可能会以不可预测的方式随选择项的大小而变化；这表明以前的研究已经误解了aDDM解决幅度敏感度的能力。在这里，我们重新分析先前的数据集，然后直接测试注意折现量是否随替代方案的规模而定。我们的分析表明，注意力折扣不会随幅度的变化而变化。该结果进一步增强了aDDM以及视觉注视可以作为幅度敏感度解释的作用。