Heterogeneity and complexity in collaborative biosecurity schemes

植物病害威胁着生态系统和景观的健康。当新的疾病威胁出现时，它们可能需要花费数百万英镑来控制和根除，而其更广泛的社会成本可能要高出数倍。积极主动的生物安保行动，包括例如加强卫生和监测，可以减少这一威胁，但这样做也会产生新的问题：政府如何激励这种行动，如何防止一些行为体从其他行为体加强生物安保中获得全球利益而不产生额外费用的搭便车行为？简单的数学模型提供了有用的见解。通过建立适当的方程来管理已知的成本和随机收益，并优化政府和每个个体代理人的策略，可以显示公私合作伙伴关系（PPP），即政府投资于生物安全并向同样这样做的代理人提供疫情补偿，可以成为一种有效的管理选择。然而，目前的模型是理想化的，考虑相同的代理和平均的相互作用，不反映代理和网络的不同景观。通过与利益相关者的接触，并应用一系列数值模拟和统计分析，这项研究计划将弥合这一差距，并帮助优先考虑干预措施。我们的目标是通过将现有理论扩展到以不同和现实的方式相互作用的异质代理，在一系列潜在疾病情景和利益相关者群体中测试PPP的实用性。我们将通过实现四个相互关联的目标来做到这一点：（1）评估公私伙伴关系中异质性和景观复杂性的影响，（2）确定面对公私伙伴关系中信息不对称的有效管理政策，（3）评估生物安全投资的持久影响如何影响预测的最佳管理战略，（4）了解生物安全联盟如何形成，以及如何以及何时可以维护它们以提供有效的全球利益。除了对寻求理解和最小化受不确定输入影响的复杂系统中的风险的社区具有学术兴趣外，我们还将与一系列利益相关者合作，将我们的数学和数值结果转化为实际结果。自然受益者包括公共机构（如Defra，环境署，自然英格兰及其下放的对等机构），但也将包括私营行业团体（如作物生产者，树木和园艺种植者以及进口商）。此外，一般的数学框架是灵活的，将探索更广泛的机会（例如，海洋疾病和入侵物种）。

Plant diseases threaten ecosystem and landscape health. When new disease threats emerge they can cost millions of pounds to contain and eradicate, and their wider social costs can be several times higher. Proactive biosecurity actions, including increased hygiene and monitoring for example, can reduce this threat, but in doing so they give rise to new problems: how can a government incentivise such actions, and how can it prevent free-riding where some agents reap the global benefits of others' increased biosecurity without incurring the additional cost? Simple mathematical models offer useful insights. By setting up appropriate equations governing known costs and random benefits, and optimising strategies for both the government and for each individual agent, it is possible to show how Private-Public Partnerships (PPPs), where governments both invest in biosecurity and offer outbreak compensation to agents who do likewise, can be an effective management option. However, current models are idealised, considering identical agents and averaged interactions which do not reflect the diverse landscape of agents and networks. By engaging with stakeholders and applying a range of numerical simulations and statistical analyses, this research programme will bridge that gap and help prioritise interventions.Our aim is to test the practicality of PPPs across a range of potential disease scenarios and stakeholder groups, by extending the existing theory to heterogeneous agents interacting in diverse and realistic ways. We will do this by addressing four linked objectives: (1) evaluate the effects of heterogeneity and landscape complexity in PPPs, (2) identify effective management policies in the face of asymmetric information in PPPs, (3) evaluate how the lasting impacts of biosecurity investments may influence the predicted best management strategies, and (4) understand how biosecurity coalitions form, and how and when they might be maintained to provide efficient global benefits.As well as being of academic interest to the communities seeking to understand and minimise risk in complex systems subject to uncertain inputs, we will work with a range of stakeholders to translate our mathematical and numerical results into practical outcomes. Natural beneficiaries include public bodies (such as Defra, Environment Agency, Natural England and its devolved equivalents) but will also include private industry groupings (such as crop producers, arbori- and horti-culturalists, and importers). Furthermore, the general mathematical framework is flexible and wider opportunities (for example, in marine diseases and invasive species) will be explored.