Department of Psychology, Southampton University, UK.
School of Psychology, Victoria University of Wellington, New Zealand.
Exp Psychol. 2022 Jan;69(1):46-59. doi: 10.1027/1618-3169/a000542.
A preference reversal is observed when a preference for a larger-later reward over a smaller-sooner reward reverses as both rewards come closer in time. Preference reversals are common in everyday life and in the laboratory and are often claimed to support hyperbolic delay-discounting models which, in their simplest form, can model reversals with only one free parameter. However, it is not clear if the temporal location of preference reversals can be predicted a priori. Studies testing model predictions have not found support for them, but they overlooked the well-documented effect of reinforcer magnitude on discounting rate. Therefore, we directly tested hyperbolic and exponential model predictions in a pre-registered study by assessing individual discount rates for two reinforcer magnitudes. We then made individualized predictions about pairs of choices between which preference reversals should occur. With 107 participants, we found (1) little evidence that hyperbolic and exponential models could predict the temporal location of preference reversals, (2) some evidence that hyperbolic models had better predictive performance than exponential models, and (3) in contrast to many previous studies, that exponential models generally produced superior fits to the observed data than hyperbolic models.
当对较大的延迟奖励的偏好相对于较小的即时奖励发生逆转时，就会观察到偏好逆转，因为两个奖励在时间上越来越接近。偏好逆转在日常生活和实验室中很常见，经常被认为支持双曲线延迟折扣模型，在最简单的形式下，该模型仅用一个自由参数就能模拟逆转。然而，目前还不清楚偏好逆转的时间位置是否可以事先预测。测试模型预测的研究没有发现对它们的支持，但它们忽略了强化物大小对折扣率的影响。因此，我们通过评估两种强化物大小的个体折扣率，在一项预先注册的研究中直接测试了双曲线和指数模型的预测。然后，我们对应该发生偏好逆转的两个选择对进行了个性化预测。通过对 107 名参与者的研究，我们发现：（1）双曲线和指数模型几乎无法预测偏好逆转的时间位置；（2）一些证据表明双曲线模型比指数模型具有更好的预测性能；（3）与许多先前的研究相反，指数模型通常比双曲线模型更能拟合观察到的数据。
