=Paper=
{{Paper
|id=Vol-2420/paperDA5
|storemode=property
|title=Improving Comprehension of Process Diagrams with Graphical Highlights
|pdfUrl=https://ceur-ws.org/Vol-2420/paperDA5.pdf
|volume=Vol-2420
|authors=Gregor Jošt
|dblpUrl=https://dblp.org/rec/conf/bpm/Jost19
}}
==Improving Comprehension of Process Diagrams with Graphical Highlights==
https://ceur-ws.org/Vol-2420/paperDA5.pdf
Improving Comprehension of Process Diagrams
with Graphical Highlights
Gregor Jošt
The Faculty of Electrical Engineering and Computer Science at the University of
Maribor, 2000 Maribor, Slovenia
gregor.jost@um.si
https://feri.um.si/en/about-us/
Business processes are core assets of organizations, and they reflect what
companies do when they deliver services or products to customers. As such, an
organization can outperform its competitors if it has more effective processes and
executes them more efficiently [5, 10]. This is reasonable, since process-oriented
structures help organizations to adapt to the increasingly changing environment
[20].
Business processes can be represented in the form of business process mod-
els, which capture both how the business works, and how the value is created
for various stakeholders [20]. In this regard, business process models aid in the
communication between the stakeholders, thus, they must be easy to understand
[9]. While business process models can be represented by means of textual de-
scription, it is a common practice to depict them graphically [3] with business
process diagrams [5].
There are many visual languages for representing business processes diagram-
matically. However, choosing the most appropriate visual language for diagram-
matic modeling is not a guarantee for a more effective communication between
the stakeholders. The effectiveness of such communication is influenced mainly
by how the intended message (i.e., how the modeler understands a diagram)
matches the received message (i.e., how the reader understands the same dia-
gram) [15]. This can become challenging to achieve, as business process diagrams
can easily become large and difficult to understand [19]. This is often due to the
complexity of the nature of the problem, which is reflected directly in the busi-
ness process diagrams. On the other hand, they can also become unnecessarily
complex, since one behavior can be modeled in different ways [11]. Indeed, one of
the most common mistakes when modeling diagrams is to display too much infor-
mation on a single diagram, which increases the diagram’s complexity needlessly
[14]. Incorrect understanding of business process diagrams can cause a variety of
issues [1], e.g., inadequate implementation of the corresponding supporting sys-
tems and other design flaws [11]. Complex business process diagrams can also
become a barrier rather than an aid to communication with stakeholders [14],
and can make it harder to determine if they capture the business practices cor-
rectly [18]. Considering this, we can conclude that the complexity of a diagram
directly affects its comprehensibility [11, 13] (sometimes used as a synonym for
understandability [4]), since there are limits in human cognitive capabilities to
make sense of complex diagrams [19].
2 G. Jošt
In this light, cognitive effectiveness of diagrams was defined as the speed,
ease, and accuracy with which a model representation can be processed by the
human mind [14]. However, cognitive effectiveness is not an inherent property
of diagrams, but it must be designed into them. To this end, nine principles for
creating cognitively effective diagrams were proposed, namely [14]:
1. Discriminability,
2. Manageable complexity,
3. Emphasis,
4. Cognitive integration,
5. Perceptual directness,
6. Structure,
7. Identification,
8. Visual expressiveness, and
9. Graphic simplicity.
Some of these principles are already integrated in the diagramming notations,
e.g., Business Process Model and Notation (BPMN) has built-in mechanisms for
managing complexity in the form of Link Events for achieving modularization
and Sub-Processes for hierarchic structuring [8]. Regardless of these built-in
mechanisms, managing complex business process diagrams is a task that is still
fraught with challenges [18]. This might also be because, according to Moody
[14], the design of diagramming notations is mostly unscientific and based on
personal taste or intuition. Indeed, some of the most predominant diagramming
notations that enable modeling of business process diagrams are perceived as
being complex and not easy to learn, even for business analysts [6]. Similarly,
modelers are typically not instructed on how to create cognitively effective dia-
grams, hence, they rely on their intuition and experience. As such, the resulting
diagrams might distort the information, or even convey unintentional messages
[14]. Hence, it is reasonable that there is a considerable body of literature re-
garding the cognitive effectiveness of business process diagrams. These studies
commonly apply the aforementioned principles for creating cognitively effective
diagrams by leveraging the extensibility of the elements’ non-standardized vi-
sual variables for displaying different kinds of information. This is also known
as secondary notation [15], which can improve the comprehension of diagrams
(e.g., associating a specific color with an organization’s role [17]). Other stud-
ies propose extensions of the existing diagramming notations [21], which do not
violate the specification, but they change the corresponding metamodel (e.g.,
simplifying temporal constructs in order to increase readability [7]).
To summarize the above, the main purpose of business process diagrams is
to facilitate the communication between the process-related stakeholders, which
directly affects the decision-making. For this reason, they must be easy to un-
derstand. However, this is often challenging to achieve, since business process
diagrams can become large and complex. In this light, the low level of modeling
competence in a casual modeler has been recognized as one of the main causes
that process diagrams lack in quality [12]. The common modeling mistakes can
make diagrams a barrier instead of an aid to communication [14], and poorly
Improving Comprehension of Process Diagrams with Graphical Highlights 3
designed diagrams may be even less effective than text [16]. To this end, many
frameworks, principles and guidelines for modeling were proposed. While they
commonly lack a sound research foundation, or are too abstract [12], several
attempts were made to provide empirically-based and operational guidance for
both designers and users of diagrams, e.g.: [14, 12, 2]. However, the majority of
these approaches intervene in the diagramming notations’ specifications or the
business process diagrams’ definition. As such, they require that the informa-
tion of applied principle is stored either in the process diagram’s model or the
diagramming notation’s metamodel. This can cause several issues, e.g., inter-
operability and compatibility between the diagrammatic tools is hindered [17].
Furthermore, overuse of specific approaches (e.g., Graphical Highlight pattern
[18]) may lead to potentially unreadable process diagrams [18].
Based on these challenges, the goal of this doctoral thesis was to propose
and investigate a non-intrusive approach that makes business process diagrams
appear less complex, without changing the corresponding diagrammatic notation
or the business process diagrams themselves. This was done by manipulating
the opacity of graphical elements in order to emphasize the important parts
of a business process diagram by lowlighting the irrelevant ones. The proposed
solution, named Emphasis, implemented with opacity-based Graphical Highlight
pattern, abbreviated as simply Graphical highlights, introduces six Structural
and seven Behavioral Graphical highlights.
Graphical highlights were firstly applied to a sample business process dia-
gram, modeled in Business Process Model and Notation (BPMN). The analysis
addressed the real-world procedure, and based on the survey of the process, we
applied one representative of Structural and one representative of Behavioral
Graphical highlight, respectively, to the conventional process diagram. After-
wards, the complexity analysis of all three process diagrams was performed.
Based on the results of the analysis, we can conclude that the application of
either Structural or Behavioral Graphical highlights decreased the complexity of
the highlighted part of the process diagram in almost all of the observed mea-
sures. In several cases this meant that understandability of the process diagram
increased.
Afterwards, a Web application prototype was implemented, which supports
the proposed set of Graphical highlights. The prototype can render the business
process diagrams and provide the support for both categories of the aforemen-
tioned Graphical highlights. The back end of the prototype was implemented
in PHP: Hypertext Preprocessor programming language, while the front end is
served using the AngularJS, a JavaScript open-source web application frame-
work, and Bootstrap, a framework for developing responsive and mobile-friendly
Graphical User Interfaces (GUIs).
Furthermore, we empirically validated whether Graphical highlights posi-
tively impact cognitive effectiveness of business process diagrams, and if the
users will find the prototype implementation useful. To this end, an experimen-
tal research, which included 85 participants, was conducted. The participants
were randomly assigned in either the treatment group (Graphical highlights di-
4 G. Jošt
agram representation approach), or the control group (conventional diagram
representation approach). In accordance with the definition of cognitive effec-
tiveness, speed, ease, and accuracy of answering 26 comprehension questions
were observed, along with the perceived usefulness of the prototype. The results
of the analysis demonstrated that participants who used Graphical highlights
significantly outperformed those that used the conventional approach in all ex-
periment’s observations.
We can conclude that using Graphical highlights increases the cognitive ef-
fectiveness of business process diagrams, while the corresponding prototype im-
plementation is perceived as being useful by the experiment’s participants. The
results supplement the related work, which demonstrated that the color-based
Graphical Highlight pattern is perceived as useful and increases the ease of use.
However, conversely from the related work, Graphical highlights do not interfere
with either the diagramming notations or with the process diagrams. Since pro-
cess diagrams are valuable organizational assets that facilitate decision-making
activities and communication, we consider Graphical highlights as a cognitive
effective mechanism that simplifies those activities further.
References
1. Cardoso, J., Mendling, J., Neumann, G., Reijers, H.A.: A Discourse on Com-
plexity of Process Models. In: Proceedings of the 2006 International Conference
on Business Process Management Workshops. pp. 117–128. BPM’06, Springer-
Verlag, Berlin, Heidelberg (2006). https://doi.org/10.1007/11837862 13, http:
//dx.doi.org/10.1007/11837862{\_}13
2. Corradini, F., Ferrari, A., Fornari, F., Gnesi, S., Polini, A., Re, B.,
Spagnolo, G.O.: A Guidelines framework for understandable BPMN
models. Data & Knowledge Engineering 113, 129 – 154 (2018).
https://doi.org/https://doi.org/10.1016/j.datak.2017.11.003, http://www.
sciencedirect.com/science/article/pii/S0169023X1630341X
3. DaSilva, C.M., Trkman, P.: Business Model: What It Is and
What It Is Not. Long Range Planning 47(6), 379 – 389 (2014).
https://doi.org/https://doi.org/10.1016/j.lrp.2013.08.004, http://www.
sciencedirect.com/science/article/pii/S0024630113000502
4. Dikici, A., Turetken, O., Demirors, O.: Factors influencing the
understandability of process models: A systematic literature re-
view. Information and Software Technology 93, 112 – 129 (2018).
https://doi.org/https://doi.org/10.1016/j.infsof.2017.09.001, http://www.
sciencedirect.com/science/article/pii/S0950584916302889
5. Dumas, M., Rosa, M.L., Mendling, J., Reijers, H.A.: Fundamentals of Business
Process Management. Springer Publishing Company, Incorporated (2013)
6. Fernández, H.F., Palacios-González, E., Garcı́a-Dı́az, V., Pelayo G-Bustelo, B.C.,
Sanjuán Martı́nez, O., Cueva Lovelle, J.M.: SBPMN - An Easier Business Process
Modeling Notation for Business Users. Comput. Stand. Interfaces 32(1-2), 18–
28 (Jan 2010). https://doi.org/10.1016/j.csi.2009.04.006, http://dx.doi.org/10.
1016/j.csi.2009.04.006
7. Gagne, D., Trudel, A.: Time-BPMN. In: Proceedings of the 2009 IEEE Conference
on Commerce and Enterprise Computing. pp. 361–367. CEC ’09, IEEE Computer
Improving Comprehension of Process Diagrams with Graphical Highlights 5
Society, Washington, DC, USA (2009). https://doi.org/10.1109/CEC.2009.71,
http://dx.doi.org/10.1109/CEC.2009.71
8. Genon, N., Heymans, P., Amyot, D.: Analysing the Cognitive Effectiveness of the
BPMN 2.0 Visual Notation. In: Proceedings of the Third International Conference
on Software Language Engineering. pp. 377–396. SLE’10, Springer-Verlag, Berlin,
Heidelberg (2011), http://dl.acm.org/citation.cfm?id=1964571.1964605
9. Gruhn, V., Laue, R.: Complexity metrics for business process models. In: 9th inter-
national conference on business information systems (BIS 2006). vol. 85, pp. 1–12
(2006)
10. Kunze, M., Luebbe, A., Weidlich, M., Weske, M.: Towards Understanding Pro-
cess Modeling – The Case of the BPM Academic Initiative. In: Dijkman, R.,
Hofstetter, J., Koehler, J. (eds.) Business Process Model and Notation: Third
International Workshop, BPMN 2011, Lucerne, Switzerland, November 21-22,
2011. Proceedings, pp. 44–58. Springer Berlin Heidelberg, Berlin, Heidelberg
(2011). https://doi.org/10.1007/978-3-642-25160-3 4, https://doi.org/10.1007/
978-3-642-25160-3{\_}4
11. Lassen, K.B., van der Aalst, W.M.P.: Complexity Metrics for
Workflow Nets. Inf. Softw. Technol. 51(3), 610–626 (Mar 2009).
https://doi.org/10.1016/j.infsof.2008.08.005, http://dx.doi.org/10.1016/j.
infsof.2008.08.005
12. Mendling, J., Reijers, H., van der Aalst, W.: Seven process modeling
guidelines (7PMG). Information and Software Technology 52(2), 127 – 136
(2010). https://doi.org/https://doi.org/10.1016/j.infsof.2009.08.004, http://www.
sciencedirect.com/science/article/pii/S0950584909001268
13. Mendling, J., Reijers, H.A., Cardoso, J.: What Makes Process Models Under-
standable? In: Proceedings of the 5th International Conference on Business Pro-
cess Management. pp. 48–63. BPM’07, Springer-Verlag, Berlin, Heidelberg (2007),
http://dl.acm.org/citation.cfm?id=1793114.1793120
14. Moody, D.: What Makes a Good Diagram? Improving the Cognitive Effectiveness
of Diagrams in IS Development. In: Wojtkowski, W., Wojtkowski, W.G., Zupancic,
J., Magyar, G., Knapp, G. (eds.) Advances in Information Systems Development:
New Methods and Practice for the Networked Society. pp. 481–492. Springer US,
Boston, MA (2007). https://doi.org/10.1007/978-0-387-70802-7 40, https://doi.
org/10.1007/978-0-387-70802-7{\_}40
15. Moody, D.: The “Physics” of Notations: Toward a Scientific Basis for Constructing
Visual Notations in Software Engineering. IEEE Transactions on Software Engi-
neering 35(6), 756–779 (Nov 2009). https://doi.org/10.1109/TSE.2009.67
16. Moody, D., van Hillegersberg, J.: Evaluating the Visual Syntax of UML: An Anal-
ysis of the Cognitive Effectiveness of the UML Family of Diagrams. In: Gašević,
D., Lämmel, R., Van Wyk, E. (eds.) Software Language Engineering. pp. 16–34.
Springer Berlin Heidelberg, Berlin, Heidelberg (2009)
17. Müller, R., Rogge-Solti, A.: BPMN for healthcare processes. In: Proceedings of the
3rd Central-European Workshop on Services and their Composition (ZEUS 2011),
Karlsruhe, Germany (2011)
18. Rosa, M.L., ter Hofstede, A.H.M., Wohed, P., Reijers, H.A., Mendling, J., van der
Aalst, W.M.P.: Managing Process Model Complexity via Concrete Syntax Modi-
fications. IEEE Transactions on Industrial Informatics 7(2), 255–265 (May 2011).
https://doi.org/10.1109/TII.2011.2124467
19. Smirnov, S., Reijers, H.A., Weske, M.: A Semantic Approach for Business Pro-
cess Model Abstraction. In: Mouratidis, H., Rolland, C. (eds.) Advanced Infor-
6 G. Jošt
mation Systems Engineering: 23rd International Conference, CAiSE 2011, Lon-
don, UK, June 20-24, 2011. Proceedings. pp. 497–511. Springer Berlin Heidelberg,
Berlin, Heidelberg (2011). https://doi.org/10.1007/978-3-642-21640-4 37, https:
//doi.org/10.1007/978-3-642-21640-4{\_}37
20. Trkman, M., Mendling, J., Krisper, M.: Using Business Process Models to Better
Understand the Dependencies Among User Stories. Inf. Softw. Technol. 71(C), 58–
76 (Mar 2016). https://doi.org/10.1016/j.infsof.2015.10.006, http://dx.doi.org/
10.1016/j.infsof.2015.10.006
21. Yousfi, A., Bauer, C., Saidi, R., Dey, A.K.: uBPMN: A BPMN
extension for modeling ubiquitous business processes. Informa-
tion and Software Technology 74(Supplement C), 55 – 68 (2016).
https://doi.org/https://doi.org/10.1016/j.infsof.2016.02.002, http://www.
sciencedirect.com/science/article/pii/S0950584916300209