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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Understanding and Improving Process Analysts' Comprehension of Process Mining Visualizations</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Femke Pieters</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>UHasselt, Digital Future Lab</institution>
          ,
          <addr-line>Agoralaan Building D, 3590 Diepenbeek</addr-line>
          ,
          <country country="BE">Belgium</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Process mining (PM) has become fundamental for data-driven process analysis. It enables organizations to identify ineficiencies and areas for improvement. Central to the efectiveness of PM is the use of visualizations and the ability of process analysts to comprehend the visualizations generated by PM algorithms. This doctoral research aims to address the challenge of enhancing the comprehensibility of PM visualizations for process analysts. The study has two key objectives: (1) to establish an improved understanding of how process analysts interpret PM visualizations and (2) to design and evaluate novel visualizations that improve comprehensibility. Through a combination of theoretical frameworks and empirical studies, this research develops an assessment framework to evaluate the comprehensibility of PM visualizations. Additionally, the research proposes novel visualization designs, which are assessed through a series of experiments to determine their impact on analysts' performance. The findings contribute to the field of PM by providing insights that can guide the design of more user-friendly visualizations, which facilitates better decision-making and process improvement within organizations.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Process Mining</kwd>
        <kwd>Comprehensibility</kwd>
        <kwd>Visualization</kwd>
        <kwd>Visual Analytics</kwd>
        <kwd>Process Analyst</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Organizations commonly conduct process analysis to pinpoint operational problems and areas for
improvement [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. These analyses are increasingly being performed in a data-driven way given the
widespread presence of process execution data captured by information systems, i.e. fine-grained data
reflecting how a process is being performed in reality. Process mining (PM) enables such data-driven
process analyses that use process execution data to, e.g., discover the activity order in a process or
expose bottlenecks [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        The great majority of PM algorithms provide a visual representation as an output such as a process
model showing the activity order [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. To actually contribute to organisational value creation by, e.g.,
identifying root causes of operational problems or process improvement opportunities, process analysts
who use PM in their profession need to make sense of the provided PM output [
        <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
        ]. Hence, it is
crucial that PM visualizations are comprehensible for process analysts such that the visualization can
efectively and eficiently satisfy their information needs [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The incomprehensibility of current PM
visualizations has emerged as an important challenge for the use of PM in organizations [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Strikingly,
there is hardly any understanding on how process analysts comprehend PM visualizations [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], even
though this is critical to guide the (re)design of PM visualizations.
      </p>
      <p>In this doctoral research, we aim to gather an in-depth understanding of process analysts’
comprehension of PM visualizations to create novel PM visualizations with improved comprehensibility.
Besides providing a highly relevant knowledge contribution, the novel visualizations enable process
analysts to better comprehend the provided output, turning PM into a more powerful instrument to
support data-driven process improvement. The two research objectives are (RO1) establish an in-depth
understanding of process analysts’ comprehension of PM visualizations and, (RO2) create and evaluate
novel PM visualizations, designed to improve comprehensibility for process analysts.</p>
      <p>The remainder of this extended abstract is structured as follows. In Section II, we describe our
research methodology. An overview of related work is given in Section III. Finally, we conclude our
research intents in Section IV.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Methodology</title>
      <p>This research will take both a theoretical and empirical perspective. The proposed research objectives
will be achieved following five iterative steps.</p>
      <p>(1) Identify common PM visualizations and related process analysis tasks (preparatory to RO1 and
RO2). To inform the selection of PM visualizations in subsequent research steps, the most common
process analysis tasks and associated PM visualizations are identified. Published PM case studies will
be collected from various sources. For each collected case study, the process analysis tasks that are
conducted are recorded, together with the PM visualizations that have been used. This step results in a
structured overview of common process analysis tasks and the associated PM visualizations used for
this task. We will validate the overview by (a) consulting the main commercial tools and (b) conducting
semi-structured interviews with academics and process analysts from industry.</p>
      <p>
        (2) Create an assessment framework to assess the comprehensibility of PM visualizations, based on theory
(RO1). A rapid review will be conducted to identify theories, guidelines and principles on (process)
visualizations and comprehensibility. As relevant literature is scattered over various fields such as
process modeling, information visualizations, visual analytics and human-computer interaction, a
systematic literature review is infeasible here. Before conducting the rapid review, we will develop an
appropriate protocol building upon Klerings et al. [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The data will be coded using the Gioia method
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], using Atlas.ti as a tool [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Drawing upon the results of the rapid review, an assessment framework
for the assessment of the comprehensibility of PM visualizations (from a theoretical perspective) will
be composed. An example theory that could be part of the assessment framework is the cognitive load
theory. This states that a visualizations should help analysts process information without overloading
their working memory. The cognitive load can be reduced by, for example, using color codes or showing
the right amount of details [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. The goal of our assessment framework is to be able to assess from a
theoretical perspective (the components of) a visualization based on its comprehensibility.
      </p>
      <p>(3) Exploratory study on process analysts’ comprehension of PM visualizations (RO1). To understand
how process analysts comprehend PM visualizations, an exploratory study, in which process analysts
will perform certain tasks to locate particular information in the visualization, will be designed and
conducted. While performing these tasks, data is collected using three complementary data collection
methods: (a) clickstream traces, (b) eye-tracking and (c) concurrent think-aloud. Using these rich
datasets, we will identify action patterns and intents of process analysts and relate this to their task
performance. The assessment framework marking the output of the previous step will be refined with
the outcomes of step 3.</p>
      <p>(4) Assess the comprehensibility of current PM visualizations (RO2). The comprehensibility of the most
common PM visualizations identified in step 1 will be assessed using the assessment framework created
in step 2 and 3. To limit the impact of personal bias, dual data extraction will be used. Based on the
assessment, various areas to improve PM visualizations to enhance their comprehensibility will emerge.
This constitutes the basis for a research agenda containing a structured overview of areas for future
research. This research agenda will not only inform step 5, but will also be highly relevant for the
research community at large. While the importance of devoting more attention to the visualization
of PM output is widely recognised at a conceptual level, this research agenda will provide specific
directions to move forward. In this way, it has the potential to generate significant impact on the future
development of the research field.</p>
      <p>
        (5) Create and evaluate novel PM visualizations (RO2). Open challenges regarding the comprehensibility
of current PM visualizations emerging from step 4 will be selected and tackled. In particular, the two
visualizations that are commonly used and show the largest potential to enhance their comprehensibility
will be selected. To create the novel PM visualizations, the procedure to design cognitively eficient
visualizations by Ware [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] will be used. An intermediate evaluation with a convenience sample of
master students will be performed. Concurrent think-aloud will be used, i.e. studentds and academics
are requested to perform the PM task using the created prototype while talking aloud. This intermediate
evaluation can provide areas to further refine the visualizations to obtain a mature prototype. Afterwards,
a between-subjects experimental design is set up, in which we evaluate the impact of the novel PM
visualizations on their comprehensibility for process analysts. Participating analysts will be randomly
assigned to one of two groups: the experimental or the control group. The visualization is the treatment
variable, but both groups will first undergo a baseline assessment to measure their initial level of PM
visualization comprehension. Following this baseline assessment, the control group will perform the
experimental tasks using the original PM visualizations and the experimental group will perform the
same tasks using the novel visualizations. Similar to step 3, the tasks will take the form of search
and recognition tasks. Task performance metrics such as accuracy, speed, and subjective ratings
of comprehension will be recorded or calculated. Clickstream traces and eye-tracking data will be
collected to contextualise the analysis. A statistical analysis (ANOVA) will be performed to compare the
performance of the experimental and control group on the collected task performance metrics, thereby
evaluating the impact of the novel PM visualizations on their comprehensibility for process analysts.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Related work</title>
      <p>
        Until now, only a limited number of works in PM literature have considered the perspective of the user
of PM algorithms. For instance, Zerbato et al. [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] identify behavioral patterns of PM users (amongst
which one process analyst from industry) that emerge during the early stages of a PM analysis. While
this paper takes the perspective of PM users, it does not provide specific insights into how process
analysts comprehend PM visualizations.
      </p>
      <p>
        Prior research from the process modeling domain has shown that a variety of factors have an impact
on process model comprehension, such as the modeling language used, the visual layout and the size of
the model [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] However, it is not clear to which extent these findings can be transferred to PM as PM
visualizations difer from traditional process models. For example, PM visualizations are embedded in
interfaces that ofer interaction functionalities. Traditional process models are less dynamic [
        <xref ref-type="bibr" rid="ref15 ref2">2, 15</xref>
        ].
      </p>
      <p>
        In more recent years, synergies between PM and the research fields of visual analytics and information
visualization have been explored. For example: Rehse et al. [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] use a visual analytics framework to
assess how current PM tools visualize the output of conformance checking, which is a very common
class of PM. This assessment highlights the need to develop and evaluate novel PM visualization idioms
(i.e. forms or types of visualizations) for conformance checking output [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. Another recent paper in
this stream of literature is Yeshchenko and Mendling [17], which reviews literature to map contributions
on the visualization of event sequences from information visualization and PM [17]. Future research can
build upon their initial observations to create novel PM visualizations. Additionally, in one systematic
study of work practices in PM, the focus lies on both visualizations and tasks. The researchers identified
that problems beyond the control-flow perspective, particularly from the case perspective, are often
analyzed using general-purpose visualization techniques. These techniques may lack the sophistication
needed to support deeper analytical insights [18].
      </p>
      <p>As mentioned in previous studies, there is a cognitive challenge faced by analysts in interpreting PM
outputs. In this context, the work from Sorokina et al. [19] contributes by proposing the PEM4PPM
model, a theoretical foundation that explains the cognitive processes of individual analysts during
the process of process mining (PPM). Cognitive steps such as task understanding, goal refinement,
data exploration and hypothesis testing play important roles in shaping how analysts approach PM
tasks. As PM visualizations are central to this process, there is a growing recognition that improving
their comprehensibility can significantly enhance analysts’ performance and efectiveness PM tools in
organizational settings [19].</p>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusion</title>
      <p>In this doctoral research, we aim to understand and improve the comprehensibility of PM visualizations.
First, we provide a highly relevant knowledge contribution by proposing an assessment framework to
assess the comprehensibility of PM visualizations. Having a better understanding of PM visualization
comprehension allows for furthering the impact of PM in organizations as process analysts can make
more sense of the output of PM algorithms. Second, we design novel visualizations and we empirically
research if the comprehensibility of these visualizations is improved.
of conformance checking, Proceedings of the 56th Hawaii International Conference on System
Sciences (2022). doi:10.48550/arXiv.2209.09712.
[17] A. Yeshchenko, J. Mendling, A survey of approaches for event sequence analysis and visualization,</p>
      <p>Information Systems 120 (2023) 102283.
[18] C. Klinkmüller, R. Müller, I. Weber, Mining process mining practices: An exploratory
characterization of information needs in process analytics, Lecture Notes in Computer Science (2019)
322–337.
[19] E. Sorokina, P. Sofer, I. Hadar, U. Leron, F. Zerbato, B. Weber, Pem4ppm: A cognitive perspective
on the process of process mining, Lecture Notes in Computer Science (2023) 465–481. doi:10.
1007/978-3-031-41620-0_27.</p>
    </sec>
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