Assessing the Expressivity of Formal Specification Languages

Formal modelling languages are powerful tools to systematically represent and analyze the properties of systems. A myriad of new modelling languages, as well as extensions of existing ones, are proposed every year. We may consider that a modelling language is useful if it allows to represent the critical aspects of systems in an expressive way. In particular, we require that the modelling language allows to accurately discriminate between correct and incorrect behaviors concerning critical aspects of the model. In this paper we present a method to assess the suitability of a modelling language to define systems belonging to a specific domain. Basically, given a system, we consider alternative correct/incorrect systems and we study whether the representations provided by the studied modelling language keep the distinction between correct and incorrect as each alternative system does.