View article

The usage of process diagrams to visualize dynamic aspects (eg work practices or business processes) of an organization can be considered a common practice in modern organizations Nolte et al.[2011]. Process diagrams can have different flavors reaching from simple hand drawn flow charts to fully fledged process models that were created by means of a software environment and adhere to a modeling standard like BPMN 1, IDEF 2, EPCs 3. Process diagrams as the visual representation of process models (or an actual process) serve as mediating artifacts and communication aids for process (re-) design activities that involve a large community of stakeholders but may as well be simply used to graphically enrich textual process documentation. Moreover, process diagrams are often used to visualize the result of process mining van der Aalst and Weijters [2004]. Process diagrams consist of graphical elements that are used to denote the various types of entities involved in a business process, eg events and activities to model the activity flow of a process and entities that are closely related to activities (eg data objects, human actors, software systems). For an exemplary process diagram see figure 1.

In the light of Bertin’s renowned Semiology of GraphicsBertin [2010] a process diagram can be seen as a graphic system consisting of a set of graphical components. Visual perception of each of these components is influenced through visual variables like size, value, texture, color, orientation, shape. While shape and orientation of graphical elements in process diagrams are largely prescribed by the modeling notation (and the implementation of this …