社会与工程心理学研究室知识库

趋利避害是生物的本能。《管子·禁藏》云:夫凡人之情,见利莫能勿就,见害莫能勿避。"两利相权取其重,两害相权取其轻"是规范性决策理论的一基本原则。本研究以金钱作为奖赏或惩罚刺激,检验人们能否理性地遵循"价值最大化"原则。在实验中,主试以检查硬币生产年代的数目为由,让被试逐枚地感受两个金钱序列:10元硬币序列(由20枚五角硬币组成)和10.3元硬币序列(由20枚五角硬币和3枚一角硬币组成),随后评定获得(或损失)各金钱序列的高兴(或不高兴)程度,并从中选择一金钱序列(与硬币等值的金钱)作为其奖赏(或惩罚)。实验为2(3枚一角硬币在序列首vs.3枚一角硬币在序列尾)×2(先检查10元硬币序列vs.先检查10.3元硬币序列)×2(损失vs.获得)三因素设计,每种条件随机分配15名商学院学生被试。结果表明,被试倾向选择获益少(10元)和损失多(-10.3元)的金钱序列;且获益大(10.3元)时高兴程度小,损失小(-10元)时不高兴程度大。这一结果意味着:"聊"并不胜于"无",反而是"无"胜于"聊"。其中,伴随着违背价值最大化原则所产生的情感亦有悖逻辑。负性情感的引发一般有其"逻辑正确"的原因(如,无惠而不乐);而引发本研究负性情感的原因实属"逻辑错误"(如,惠多而不乐)。这种不曾被定义而类似于"冤"的情感不仅见于个人,也见于民族、国家间的持续交往,值得进一步研究。

Triggered by an observation that adding an additional small gain/loss can devalue an overall positive/negative evaluation,this research explores whether a monotonically increasing relationship between utility and value could be robust enough to survive a retrospective evaluation of monetary stimuli. Participants reviewed pairs of options that included one option that was a total of $10（20 × 50￠ coins） and another that was a total of $10.3（20 × 50￠ plus an additional 3 × 10￠） ,and then were asked to rate how pleasant if receiving an option＇s equivalent reward and how unpleasant if receiving the same amount of fine. A significant majority of participants preferred the smaller/larger option and rated it more pleasant/less unpleasant. This implies that ‘a little is not better than nothing’,but rather that ‘nothing can be better than a little’. A resentment-like feeling as a cause of the observed violation of a monotonically increasing relationship between monetary value and utility is also discussed.