On the Semantic Transparency of Declarative Process Models: The Case of Constraints

Abstract

Process modeling notations are essential for analyzing, designing, improving, and digitalizing business processes in organizations. In particular, for knowledge-intensive processes, notations that allow flexible orchestration of activities are crucial for supporting discretionary work. Declarative Process Modeling notations allow describing the interplay between the process activities with constraints that need to be met, without specifying how to meet them. Despite being well-suited for modeling flexible processes, declarative notations are not as widely adopted as imperative notations where the process is usually depicted using a flow-based approach. This paper focuses on investigating the semantic transparency of declarative notations, specifically how the visual representation of constraints aligns with the underlying formal concepts used in Declarative Process Models (DPMs). The study concentrates on Dynamic Condition Response (DCR) Graphs, a representative notation of DPMs extensively used in industry and academia. The research employs semi-structured interviews with experts in DCR Graphs, as well as an analysis of semantic transparency based on theoretical models of understandability. The findings indicate that generally colors contribute to the understanding of relations in DPMs, while the shapes used to describe constraints do not accurately convey their semantics. Based on these results, the study proposes an alternative representation of constraints, paving the road for an enhanced representation of DPMs.