Exploring the Effectiveness of Normative i* Modelling: Results from a Case Study on Food Chain Traceability

This paper evaluates the effectiveness of an extension to i* modelling – normative i* modelling – during the requirements analysis for new sociotechnical systems for food traceability. The i* focus on modelling systems as networks of heterogeneous, inter-dependent actors provides limited support for modelling system-wide properties and norms, such as laws and regulations, that also influence the specification of socio-technical systems. In this paper we introduce an extension to i* to model and analyse norms, then apply it to model laws and regulations applicable to European food traceability systems. We report an analysis of the relative strengths and weaknesses of this extended form of i* with its traditional forms, and use results to answer two research questions about the usefulness and usability of the i* modelling extension.