Methodologies and Tools for Integrated Systems Modelling

OECD and IIASA’s modelling tools are presented and the needs of a new generation of tools are outlined. Next-generation systems analysis models have to better integrate real-world dynamics such as social and behavioural heterogeneity. This will help to represent social dynamics and complex collective decision-making and facilitate the evaluation of the effectiveness of policies and their systemic impacts. A promising approach is to integrate existing modelling tools from different fields, for example linking environmental models with economic growth and trade models. This extends the boundaries of what is modelled and allows for broader ranges of interactions to assess policy interventions. Going beyond the integration of existing tools may involve pioneering applications and innovative methodologies and tools in several areas, including explicit accounting for uncertainty; multiple agents with strategic interactions; bounded rationality, including consumption preferences and consumer choices; and network effects linked to complex interconnectedness and systemic risks.