John Krogstie: Quality of models and modeling languages

Over the years, we have developed a generic framework for understanding quality of model called SEQUAL. SEQUAL has the following properties: 

• It distinguishes between goals and means by separating what you are trying to achieve (quality of models) from how to achieve it.
• It can be used for evaluation of models and modelling languages in general, but can also be extended for the evaluation of particular types of models also on the instance level.
• It is closely linked to linguistic and semiotic concepts. In particular, the core of the framework including the discussion on syntax, semantics, and pragmatics is related to the use of these notions in the semiotic theory of Morris.
• It is based on a constructivistic world-view, recognizing that models are usually created as part of a dialogue between the participants involved in modelling, whose knowledge of the modelling domain and potentially the domain itself changes as modelling takes place.

The framework has been used for evaluation of modelling and modelling languages of a large number of perspectives, including data, object, process, enterprise, and goal-oriented modelling.