School of Psychology, Georgia Institute of Technology.
Psychol Sci. 2021 Jul;32(7):1157-1168. doi: 10.1177/0956797621994214. Epub 2021 Jul 1.
Humans exhibit substantial biases in their decision making even in simple two-choice tasks, but the origin of these biases remains unclear. I hypothesized that one source of bias could be individual differences in sensory encoding. Specifically, if one stimulus category gives rise to an internal-evidence distribution with higher variability, then responses should optimally be biased against that stimulus category. Therefore, response bias may reflect a previously unappreciated subject-to-subject difference in the variance of the internal-evidence distributions. I tested this possibility by analyzing data from three different two-choice tasks (s = 443, 443, and 498). For all three tasks, response bias moved in the direction of the optimal criterion determined by each subject's idiosyncratic internal-evidence variability. These results demonstrate that seemingly random variations in response bias can be driven by individual differences in sensory encoding and are thus partly explained by normative strategies.
人类在进行简单的二选一任务时，决策会出现明显的偏差，但这些偏差的来源尚不清楚。我假设，造成偏差的一个原因可能是感官编码上的个体差异。具体来说，如果一个刺激类别产生的内部证据分布具有更高的可变性，那么针对该刺激类别的反应应该会出现最优偏差。因此，反应偏差可能反映了内部证据分布方差上以前未被重视的个体间差异。我通过分析三个不同的二选一任务（s = 443、443 和 498）的数据来检验这一可能性。对于所有三个任务，反应偏差都朝着由每个被试特有的内部证据可变性决定的最优标准移动。这些结果表明，反应偏差中看似随机的变化可以由感官编码上的个体差异驱动，因此部分可以用规范性策略来解释。
