Product-service system (PSS) business models appraise the relationship between different stakeholders and focus on a partnership based on profit. Existing literature discusses servitization and the associated cost-benefit analysis (CBA) models mostly from the perspective of original equipment manufacturers. Additionally, CBA is typically conducted using top-down approaches and standard activity-based costing, with limited available data and without considering uncertainty. As a result, inadequate and under-priced contract decisions may be made. To address the problem, this paper extends the current literature by proposing a novel framework for quantifying uncertainty in cost and benefit estimates of PSS contracts. The framework offers a bottom-up costing approach using the agent-based simulation technique. The framework comprises a stochastic CBA model for PSS. It is developed by considering through-life cost and benefit of products and services with aggregate uncertainty in terms of service costs, service lead-times, and their occurrences. The framework has been tested successfully on a real-world case study with a bespoke service provider in the machine tool industry. The model is applied to include spare-parts and availability-based servitization contracts. The simulation results are validated by real-world measurements and expert knowledge. The results involve a comprehensive stochastic analyses of a through-life CBA under probabilistic uncertainty and provide the opportunity to quantify the uncertainty in PSS contract decisions. Moreover, the results highlight that servitization is more beneficial for bespoke service providers in long-term contracts, and for relatively new or retrofitted products. Further research works are required to apply the model on capability-based contracts.

产品服务系统（PSS）业务模型评估不同利益相关者之间的关系，并专注于基于利润的合作伙伴关系。现有文献主要从原始设备制造商的角度讨论服务化和相关的成本效益分析（CBA）模型。此外，CBA通常使用自上而下的方法和基于活动的标准成本法进行，可提供的数据有限且不考虑不确定性。结果，可能会做出不充分且价格过低的合同决策。为了解决这个问题，本文通过提出一种用于量化PSS合同成本和收益估算不确定性的新颖框架，扩展了现有文献。该框架使用基于代理的模拟技术提供了一种自下而上的成本核算方法。该框架包括用于PSS的随机CBA模型。它是通过考虑产品和服务的整个生命周期成本和收益而在服务成本，服务提前期及其发生方面存在总体不确定性的。该框架已在机床行业的定制服务提供商的真实案例研究中成功测试。该模型适用于包括备件和基于可用性的服务合同。仿真结果通过实际测量和专家知识进行验证。结果涉及在概率不确定性下对整个生命周期CBA的全面随机分析，并为量化PSS合同决策中的不确定性提供了机会。此外，结果表明，对于长期合同中的定制服务提供商以及相对较新的或翻新的产品，服务化更有利。需要进一步的研究工作以将该模型应用于基于能力的合同。