The Influence of Notational Deficiencies on Process Model Comprehension

Visual process models are helpful when analyzing and improving complex organizational processes. However, the symbol sets used in different modeling notations vary in perceptual discriminability, visual expressiveness, and semantic transparency; such factors are likely to influence a notation’s perception and cognitive effectiveness. In this paper, we investigate whether the basic symbol sets in visual process modeling languages influence comprehension and cognitive load of process models. For this purpose, we analyze four different symbol sets in an experiment with model comprehension tasks carried out by 136 participants. Our results indicate that notational deficiencies concerning perceptual discriminability and semiotic clarity have measurable effects on comprehension, cognitive load, and the time needed to understand the models.