Aiding the development of the conceptual model for hybrid simulation: Representing the modelling frame

Hybrid simulation has emerged as a popular method of modelling complex systems and addressing real-world problems. However, in the existing literature, there is no clear method for documenting the approach of a hybrid simulation study. We aim to address this problem by presenting a method for general representation of the modelling frame, i.e. the choice and combination of modelling approaches, in hybrid modelling studies. To demonstrate the use of the representation method, we retrospectively compare and contrast two real-world examples of hybrid simulation undertaken to support the rail operations of Eurostar International Limited. We discuss the advantages of our proposed representation method in distilling the key features and aims of a hybrid simulation study and show how our representation method can be used as a tool for communicating to other modellers and stakeholders the value added from hybridisation. We further discuss, how our representation method can be used at any stage throughout the model development process including to support the conceptual modelling activity when undertaking a hybrid simulation study.