This paper presents the results of a threshold public goods game experiment with heterogeneous players. The experiment is designed in close collaboration with the Dutch association of agri-environmental farmer collectives. Subjects are recruited at a university (study 1) and a farm management training centre (study 2), the subjects of the second study most resembling the subjects in the field. The experiment consists of several treatments and each treatment has two different distribution rules, which are varied in a within-subjects manner. After subjects have experienced both, they can vote for one of the two rules: either a differentiated bonus that results in equal payoff for all, or an undifferentiated, equal share of the group bonus. In a between-subjects manner, subjects can vote for a (minimum or average) threshold or are faced with an exogenous threshold. The results indicate that exogenous thresholds perform better, possibly because the focal point they provide facilitates coordination. With regard to the two distribution rules, the results are mixed: in study 1, average contributions and payoffs are higher under the 'equal-payoff' rule, but there is no significant difference between the two in study 2. Overall, our results suggest that environmental payment schemes should consider cost heterogeneity in the design of group contracts, and pay explicit attention to coordination problems too.

中文翻译：

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使用阈值公共物品实验分析群体契约设计

本文介绍了异质玩家的阈值公共产品博弈实验结果。该实验是与荷兰农业环境农民集体协会密切合作设计的。在大学（研究 1）和农场管理培训中心（研究 2）招募受试者，第二项研究的受试者与该领域的受试者最相似。实验由几个处理组成，每个处理有两个不同的分布规则，它们以受试者内的方式变化。受试者都经历过这两种情况后，他们可以投票支持两种规则中的一种：要么是导致所有人平等回报的差异化奖金，要么是无差异的、平等份额的团体奖金。以被试间的方式，受试者可以投票支持（最小或平均）阈值或面临外生阈值。结果表明外生阈值表现更好，可能是因为它们提供的焦点促进了协调。关于这两种分配规则，结果好坏参半：在研究 1 中，平均贡献和回报在“等回报”规则下更高，但在研究 2 中两者之间没有显着差异。 总的来说，我们的结果表明环境支付方案在设计团体合同时应考虑成本异质性，并明确关注协调问题。