We examine the role of reciprocity enabled by digital social platforms for offline healthy behavior. Although reciprocity is a fundamental aspect of human psychology, its application in promoting healthy behavior has been limited. We conduct a randomized field experiment with over 1,700 pairs of users on a mobile social network platform. Individuals in the reciprocity treatment group receive a gift from their friends and are asked to return this favor by participating in a running challenge. Their performance is compared to the self-interest incentives widely used in practice. Building on social exchange theory, we argue that reciprocity-based incentives will outperform self-interest incentives with modest reward for motivating behavior change. We find that, on average, reciprocity is stronger than self-interest in inducing exercise behavior by a substantial amount. Furthermore, our results reveal that the magnitude of the reciprocity effect is contingent on the social closeness between senders and receivers. Interestingly, social closeness has an inverted U-shaped influence on the reciprocity effect. The effect is strongest when closeness is moderate, and wanes when closeness is either too strong or too weak. Compared to commonly used self-interest based financial incentives, our findings offer a potentially more powerful avenue for mechanism design in promoting healthy behavior.

中文翻译：

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互惠还是自利？利用数字社交联系促进健康行为

我们研究了数字社交平台对离线健康行为的互惠作用。尽管互惠是人类心理学的一个基本方面，但它在促进健康行为方面的应用受到限制。我们在移动社交网络平台上对超过 1,700 对用户进行了随机现场实验。互惠治疗组的个人收到朋友的礼物，并被要求通过参加跑步挑战来回报这份恩惠。他们的表现与实践中广泛使用的自利激励进行了比较。基于社会交换理论，我们认为基于互惠的激励将优于自我利益激励，而激励行为改变的奖励适度。我们发现，平均而言，在大量诱导运动行为方面，互惠比自身利益强。此外，我们的结果表明，互惠效应的大小取决于发送者和接收者之间的社会亲密度。有趣的是，社会亲密度对互惠效应具有倒 U 型影响。当接近度适中时，效果最强，而当接近度太强或太弱时，效果就会减弱。与常用的基于自身利益的财务激励措施相比，我们的研究结果为促进健康行为的机制设计提供了一种潜在的更强大的途径。社会亲密度对互惠效应有倒U型影响。当接近度适中时，效果最强，而当接近度太强或太弱时，效果就会减弱。与常用的基于自身利益的财务激励措施相比，我们的研究结果为促进健康行为的机制设计提供了一种潜在的更强大的途径。社会亲密度对互惠效应有倒U型影响。当接近度适中时，效果最强，而当接近度太强或太弱时，效果就会减弱。与常用的基于自身利益的财务激励措施相比，我们的研究结果为促进健康行为的机制设计提供了一种潜在的更强大的途径。