From a system dynamics causal loop diagram to an object-role model: A stepwise approach

Two diagrams are most commonly used in System Dynamics (SD); Causal Loop Diagrams (CLDs) and Stock and Flow Diagrams (SFDs). CLDs are qualitative in nature while SFDs are quantitative. In this paper we draw our attention to CLDs. CLDs are visual representation of dynamic influences with inter-relationships amongst a collection of SD variables. They are used to qualitatively capture structures and interactions of feedback loops. CLDs however, have been found to be ambiguous, lack detail and not easy to conceptualize. In this paper therefore, we come up with steps on how to transfer information from a CLD into an Object Role Modeling (ORM) model. We carry out this study to improve CLD model conceptualization, make CLD variables explicit and to reduce on CLD model ambiguity. To achieve this we use ORM, a fact oriented method whose focus is on domain conceptualization through data modeling because of its conceptual focus and roots in verbalization, graphical expressiveness and well defined semantics. To apply and validate these steps, we use a case as an example in focus session setting. From these focus sessions, evaluations and discussion of results are made and finally conclusions are drawn.