This paper presents an agent-based model that explores the conditions for ongoing participation in community gardening projects. We test the e ects of Ostrom’s well-known Design Principles for collective action anduse an extensive database collected in 123 cases inGermany and two case studies in theNetherlands to validate it. Themodel uses the Institutional Analysis andDevelopment (IAD) framework and integrates decision mechanisms derived from the Theory of Reasoned Action (TRA). This allows the analysis of volunteer participation in urban community gardens over time, based on the garden’s institutions (Design Principles) and the volunteer’s intention to join gardening. This intention is influenced by the volunteer’s expectations and past experiences in the garden (TRA). We find that not all Design Principles lead to higher levels of participation but rather, participation depends on specific combinations of the Design Principles. We highlight the need to update the assumption about sanctioning in such systems: sanctioning is not always beneficial, and may be counter-productive in certain contexts.

中文翻译：

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维持城市社区花园的集体行动

本文提出了一个基于代理的模型，该模型探讨了持续参与社区园艺项目的条件。我们测试了 Ostrom 著名的集体行动设计原则的效果，并使用在德国的 123 个案例和荷兰的两个案例研究中收集的广泛数据库来验证它。该模型使用制度分析与发展 (IAD) 框架，并整合源自理性行动理论 (TRA) 的决策机制。这允许根据花园的机构（设计原则）和志愿者加入园艺的意图，对志愿者参与城市社区花园的时间进行分析。这一意图受到志愿者的期望和过去在花园 (TRA) 中的经历的影响。我们发现并非所有设计原则都会导致更高水平的参与，而是参与取决于设计原则的特定组合。我们强调需要更新关于此类系统中制裁的假设：制裁并不总是有益的，在某些情况下可能会适得其反。