Maximising stakeholder learning by looping again through the simulation life-cycle: A case study in public transport

Building a simulation model of a complex system requires significant investment of expertise, time, and expense. In order for an organisation to realise the greatest return on this investment, it is advantageous to re-use a model or extend the simulation model's life-cycle to maximise learning generated from it. Existing studies typically end after a 'single loop' of the simulation life-cycle, with the computer model produced at the end of it suitable for addressing the initial requirements of stakeholders. Here we explore how to further extend the modelling life-cycle by adding a 'second loop' in which an existing simulation model is introduced to a new group of stakeholders and then enhanced to capture additional features of the system that are of interest to this new group, but were not identified as requirements by the first group. Developed from real-world experience working with the large train operator Eurostar International Limited, we present details of our proposed methodological framework and highlight the tangible benefits of adding a second loop to the simulation life-cycle. We discuss the roles of modellers and stakeholders in the two loops of the life-cycle and compare and contrast the relationship between the two parties in each.