Data from: Are capuchin monkeys (Sapajus spp.) sensitive to lost opportunities? The role of opportunity costs in intertemporal choice

Principles of economics predict that the costs associated with obtaining rewards can influence choice. When individuals face choices between a smaller, immediate option and a larger, later option, they often experience opportunity costs associated with waiting for delayed rewards because they must forego the opportunity to make other choices. We evaluated how reducing opportunity costs affects delay tolerance in capuchin monkeys. After choosing the larger option, in the High cost condition subjects had to wait for the delay to expire, whereas in the Low cost different condition they could perform a new choice during the delay. To assess the effect of intake rate on choices, the Low cost same condition had the same intake rate ratio as the High cost condition. We found that capuchins attended both to intake rates and to opportunity costs. They chose the larger option more often in the Low cost different and Low cost same conditions than in the High cost condition, and more often in the Low cost different condition than in the Low cost same condition. Understanding how non-human primates represent and use costs in making decisions not only helps to develop theoretical frameworks to explain their choices but also addresses similarities with and differences from human decision making. These outcomes provide insights into the origins of human economic behaviour.

经济学原理表明，获取奖励所需承担的相关成本会对决策选择产生影响。当个体在即时可得的小额奖励与延时的大额奖励之间进行抉择时，往往会因等待延迟奖励而面临机会成本——因为他们不得不放弃做出其他选择的机会。本研究评估了机会成本的降低如何影响卷尾猴的延迟满足容忍度。在选择大额奖励选项后，高成本条件（High cost condition）下的被试需等待延迟时长结束方可获得奖励；而在不同低代价条件（Low cost different condition）中，被试可在延迟时段内发起新的选择任务。为评估摄入速率对决策的影响，同型低代价条件（Low cost same condition）与高成本条件的摄入速率比值保持一致。研究结果显示，卷尾猴的决策同时兼顾了摄入速率与机会成本：相较于高成本条件，卷尾猴在不同低代价条件与同型低代价条件中选择大额奖励选项的频率更高；且在不同低代价条件下的选择频率高于同型低代价条件。阐明非人类灵长类动物如何表征并运用成本进行决策，不仅有助于构建解释其选择行为的理论框架，还能为揭示人类决策的异同提供参考。本研究结果可为人类经济行为的起源研究提供新的视角。