Schuck-Paim Cynthia, Pompilio Lorena, Kacelnik Alex
Zoology Department University of Oxford United Kingdom.
PLoS Biol. 2004 Dec;2(12):e402. doi: 10.1371/journal.pbio.0020402. Epub 2004 Nov 23.
Normative models of choice in economics and biology usually expect preferences to be consistent across contexts, or "rational" in economic language. Following a large body of literature reporting economically irrational behaviour in humans, breaches of rationality by animals have also been recently described. If proven systematic, these findings would challenge long-standing biological approaches to behavioural theorising, and suggest that cognitive processes similar to those claimed to cause irrationality in humans can also hinder optimality approaches to modelling animal preferences. Critical differences between human and animal experiments have not, however, been sufficiently acknowledged. While humans can be instructed conceptually about the choice problem, animals need to be trained by repeated exposure to all contingencies. This exposure often leads to differences in state between treatments, hence changing choices while preserving rationality. We report experiments with European starlings demonstrating that apparent breaches of rationality can result from state-dependence. We show that adding an inferior alternative to a choice set (a "decoy") affects choices, an effect previously interpreted as indicating irrationality. However, these effects appear and disappear depending on whether state differences between choice contexts are present or not. These results open the possibility that some expressions of maladaptive behaviour are due to oversights in the migration of ideas between economics and biology, and suggest that key differences between human and nonhuman research must be recognised if ideas are to safely travel between these fields.
经济学和生物学中的规范性选择模型通常期望偏好能在不同情境下保持一致，用经济学的语言来说就是“理性的”。在大量文献报道了人类存在经济上的非理性行为之后，动物的非理性行为最近也被描述了出来。如果这些发现被证明是系统性的，那么它们将挑战长期以来生物学中关于行为理论化的方法，并表明与那些被认为会导致人类非理性行为的认知过程类似的过程，也可能阻碍对动物偏好进行建模的最优方法。然而，人类和动物实验之间的关键差异尚未得到充分认识。虽然可以从概念上指导人类理解选择问题，但动物需要通过反复接触所有可能情况来进行训练。这种接触往往会导致不同处理之间的状态差异，从而在保持理性的同时改变选择。我们报告了对欧洲椋鸟的实验，结果表明明显的非理性行为可能源于状态依赖性。我们发现，在一个选择集中添加一个较差的选项（一个“诱饵”）会影响选择，这种效应以前被解释为非理性的表现。然而，这些效应会根据选择情境之间是否存在状态差异而出现或消失。这些结果表明，某些适应不良行为的表现可能是由于经济学和生物学之间思想迁移时的疏忽所致，并且表明，如果要使思想在这些领域之间安全传播，就必须认识到人类和非人类研究之间的关键差异。
