As humans, we are unique with respect to the flexibility and scope of our cooperative behavior. In recent years, considerable research has been devoted to investigating the psychological mechanisms which support this. One key finding is that people frequently calibrate their effort level to match a cooperation partner's effort costs - although little is known about exactly why they do so. We hypothesized that people calibrate with the ultimate goal of attracting and keeping good collaboration partners, with the proximal psychological motive being a preference for fairness. Across four lab-based, pre-registered experiments ( = 142), we found support for these hypotheses, and distinguished them from plausible alternative explanations, such as the conjecture that people may use their partner's effort costs as information to infer the value of opportunities afforded by their environment, and the conjecture that people may calibrate their effort investment in order to appear competent. As humans, we have unique skills and motivations for acting together. Crucially, acting together requires effort and a growing body of empirical work on cooperation and joint action suggests that people calibrate their effort level to match that of a partner's effort costs - although little is known about the mechanisms leading them to do so. Our findings show that people calibrate their effort investment in joint action with the ultimate goal of attracting and keeping good collaboration partners and that the psychological mechanism that drives them to do so is a preference for fairness. These findings provide a valuable addition to existing research on the sense of fairness, providing evidence that the sense of fairness leads people not only to distribute resources according to individual effort costs but to distribute effort costs according to the expected reward distribution as well.

中文翻译：

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联合行动中基于努力的决策：公平感的证据

作为人类，我们在合作行为的灵活性和范围方面是独一无二的。近年来，大量研究致力于调查支持这一点的心理机制。一个重要的发现是，人们经常调整自己的努力水平，以匹配合作伙伴的努力成本——尽管很少有人知道他们这样做的确切原因。我们假设，人们的最终目标是吸引和留住良好的合作伙伴，最接近的心理动机是对公平的偏好。在四个基于实验室的预先注册的实验 (= 142) 中，我们发现了对这些假设的支持，并将它们与看似合理的替代解释区分开来，例如人们可能使用其合作伙伴的努力成本作为信息来推断机会价值的猜想他们的环境所提供的，以及人们可能会调整他们的努力投入以显得有能力的推测。作为人类，我们拥有共同行动的独特技能和动机。至关重要的是，共同行动需要付出努力，越来越多的关于合作和联合行动的实证研究表明，人们会调整自己的努力水平，以匹配合作伙伴的努力成本——尽管人们对导致他们这样做的机制知之甚少。我们的研究结果表明，人们调整他们在联合行动中的努力投入，最终目标是吸引和留住良好的合作伙伴，而驱使他们这样做的心理机制是对公平的偏好。这些发现为现有关于公平感的研究提供了有价值的补充，提供了证据表明公平感不仅导致人们根据个人努力成本分配资源，而且还根据预期奖励分配来分配努力成本。