<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Python Tool for Object-Centric Process Mining Comparison (Extended Abstract)</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Anahita Farhang Ghahfarokhi</string-name>
          <email>farhang@pads.rwth-aachen.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Wil M.P. van der Aalst</string-name>
          <email>wvdaalst@rwth-aachen.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Process and Data Science (Informatik 9), RWTH Aachen University</institution>
          ,
          <addr-line>Aachen</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2021</year>
      </pub-date>
      <abstract>
        <p>-Object-centric process mining provides a more holistic view of processes where we analyze processes with multiple case notions. However, most object-centric process mining techniques consider the whole event log rather than the comparison of existing behaviors in the log. In this paper, we introduce a stand-alone object-centric process cube tool built on the PM4PYMDL process mining framework. Our infrastructure uses both object and event attributes to build the process cube which leads to different types of materialization. Furthermore, our tool is equipped with the state of the art object-centric process mining techniques. Through our tool the user can visualize the extracted object-centric event log from process cube operations, export the object-centric event log, discover the state-of-the-art objectcentric process model for the extracted log, and compare the process models side-by-side. Index Terms-Object-Centric Process Mining, Object-Centric Event Logs, Process Comparison, Process Cubes</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>
        Process mining is a field of data science that aims to
bridge the gap between business process model-based
analysis and data-oriented analysis. Process mining techniques
include process discovery, conformance checking, and process
enhancement methods [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>
        Event logs are the starting point to apply process mining
techniques. Event logs consist of events where each event
refers to one case notion, activity, timestamp, and some
additional attributes such as resource. Common process mining
techniques are based on event logs with one case notion,
however, in reality, several case notions are involved in one
process, e.g., a simple Order-to-Cash (O2C) process where
orders, offers, and invoices are involved. Object-centric
process mining is a novel branch of process mining that aims
to develop process mining techniques on top of
ObjectCentric Event Logs (OCELs) [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Initial approaches have been
developed to extract OCEL logs from information systems [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ],
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] and discover process models from OCEL logs [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
However, there may exist a variety in object-centric processes
that requires the separation of different processes from each
other [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Therefore, process cubes are introduced that are
inspired by the notion of OLAP and are developed to compare
processes with each other through process cube operations
such as slice and dice [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Several implementations of process
cubes are developed [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. However, they cannot support
event logs with multiple objects, i.e., OCEL logs.
      </p>
      <p>
        In this demo paper, we present an interactive tool that
permits the user to compare object-centric processes with each
other through process cube operations. Furthermore, it permits
to discover object-centric process models (object-centric
Directly Follows Graphs [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], Object-Centric Petri Nets [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]) and
compare the process models side-by-side.
      </p>
      <p>The remainder of this paper is organized as follows. In
Section II, we describe the main functionalities of the tool
that are provided. In Section III, we evaluate the scalability of
the tool. Finally, Section IV concludes the paper and presents
some future work for the extension of our work.</p>
    </sec>
    <sec id="sec-2">
      <title>II. OBJECT-CENTRIC PROCESS CUBES</title>
      <p>In our open-source tool1, called OCPC (Object-Centric
Process Cube), we have used Tk GUI toolkit as the user
interface which is one of the popular standard Python
interfaces. A snapshot of the tool is shown in Figure 1 where three
sub windows are highlighted:</p>
      <p>Input: the input is JSON-OCEL/XML-OCEL. In OCEL,
an event is related to event attributes and some possible
objects related to that event. Furthermore, each object
can have its own properties in another table. Therefore, as
shown in Figure 1, in the first highlighted sub window, we
have shown events with event attributes and their objects
in one table, whereas, objects within their attributes
are shown in separate tables. The user can select event
attributes and object attributes as the dimensions of the
process cube and build the cube.</p>
      <p>Wizard: After creating the cube, we see overviews of the
cube in the second sub window. It is possible to select
dimensions of the cube as rows and columns and see the
number of events in the selected slices/dices.</p>
      <p>The combo box ”Materialization” is related to design
choices that we have in this tool for materializing that did
not exist in the previous process cubes. In the ”Existence”
option for materialization, there should exist an object
in that event that satisfies the property. For example, in
the left-view in Figure 1, the option is ”Existence” and
the highlighted green dice in this view shows in 557
events Echo show 8 was involved. In the ”All” option
1https://github.com/AnahitaFarhang/object-centric-process-cube
for materialization, all the objects, in the event, should
satisfy that property. An example is shown in right-view
where this option is ”All”. The highlighted green cell
in this view shows that in 8 events all the items were
Echo show 8.</p>
      <p>Output: In the third sub window, we have compared
the process models of the selected cells shown in the
second sub window. As we see, there are differences in
the duration of activities for the selected cells.
Furthermore, depending on the operation selection in the second
sub window, it is possible to compare the extracted event
logs, and Object-Centric Petri nets of the selected cells.</p>
    </sec>
    <sec id="sec-3">
      <title>III. SCALABILITY</title>
      <p>The scalability of the tool in terms of number of events,
event attributes, and object attributes are shown in Tables I, II,
and III, respectively2. The result of the analysis with different
settings shows the time required for creating the cube increases
linearly, linearly, and non-linearly when increasing the number
of events, event attributes, and object attributes, respectively.
These relationships are justifiable by the nature of OCELs
where an event can contain multiple objects and there is a
oneto-many relationship between an event and its objects which
results in a non-linear relationship shown in Table III.</p>
    </sec>
    <sec id="sec-4">
      <title>IV. CONCLUSION</title>
      <p>Here, we present an interactive object-centric process cube
tool that enables the exploration, discovery of object-centric
2All the above experiments were performed on a laptop with the
specifications: PC Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz.
process models along with side-by-side model comparison.
Using the tool that is implemented in PM4PY-MDL, users
explore object-centric event logs using process cube operations,
export the partitioned OCEL, and discover the object-centric
process models, annotated with frequency and performance,
which helps in understanding processes better. A video
displaying the functionalities of our tool is available at the address
https://youtu.be/zenHt3wdZP4. We aim in the future to extend
this tool with an automatic method to choose interesting slices
and dices to explore the cube.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>A.</given-names>
            <surname>Berti</surname>
          </string-name>
          and
          <string-name>
            <surname>W.M.P. van der Aalst.</surname>
          </string-name>
          <article-title>Extracting multiple viewpoint models from relational databases</article-title>
          .
          <source>In SIMPDA</source>
          , volume
          <volume>379</volume>
          , pages
          <fpage>24</fpage>
          -
          <lpage>51</lpage>
          ,
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>A.</given-names>
            <surname>Bolt</surname>
          </string-name>
          and
          <string-name>
            <given-names>W.M.P. van der</given-names>
            <surname>Aalst</surname>
          </string-name>
          .
          <article-title>Multidimensional process mining using process cubes</article-title>
          .
          <source>In BPMDS</source>
          , volume
          <volume>214</volume>
          , pages
          <fpage>102</fpage>
          -
          <lpage>116</lpage>
          ,
          <year>2015</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>D.</given-names>
            <surname>Cohn</surname>
          </string-name>
          and
          <string-name>
            <given-names>R.</given-names>
            <surname>Hull</surname>
          </string-name>
          .
          <article-title>Business artifacts: A data-centric approach to modeling business operations and processes</article-title>
          .
          <source>IEEE Data Eng. Bull.</source>
          ,
          <volume>32</volume>
          :
          <fpage>47</fpage>
          -
          <lpage>59</lpage>
          ,
          <year>2009</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <given-names>E.</given-names>
            <surname>G.L de Murillas</surname>
          </string-name>
          .
          <article-title>Process mining on databases: Extracting event data from real-life data sources</article-title>
          .
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>A.</given-names>
            <surname>Farhang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Berti</surname>
          </string-name>
          , and
          <string-name>
            <surname>W.M.P. van der Aalst.</surname>
          </string-name>
          <article-title>Process comparison using object-centric process cubes</article-title>
          .
          <source>arXiv:2103.07184</source>
          ,
          <year>2021</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <given-names>A.</given-names>
            <surname>Farhang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>G.</given-names>
            <surname>Park</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Berti</surname>
          </string-name>
          , and
          <string-name>
            <surname>W.M.P. van der Aalst. OCEL:</surname>
          </string-name>
          <article-title>A standard for object-centric event logs</article-title>
          .
          <source>In SIMPDA</source>
          , pages
          <fpage>169</fpage>
          -
          <lpage>175</lpage>
          . Springer,
          <year>2021</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>E.H.J.</given-names>
            <surname>Nooijen</surname>
          </string-name>
          ,
          <string-name>
            <surname>B.F. van Dongen</surname>
          </string-name>
          ,
          <string-name>
            <given-names>and D.</given-names>
            <surname>Fahland</surname>
          </string-name>
          .
          <article-title>Automatic discovery of data-centric and artifact-centric processes</article-title>
          .
          <source>In BPM Workshops</source>
          , volume
          <volume>132</volume>
          , pages
          <fpage>316</fpage>
          -
          <lpage>327</lpage>
          ,
          <year>2012</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <given-names>J.T.S.</given-names>
            <surname>Ribeiro</surname>
          </string-name>
          and
          <string-name>
            <surname>A.J.M.M. Weijters</surname>
          </string-name>
          .
          <article-title>Event cube: Another perspective on business processes</article-title>
          .
          <source>In OTM</source>
          , volume
          <volume>7044</volume>
          , pages
          <fpage>274</fpage>
          -
          <lpage>283</lpage>
          ,
          <year>2011</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <surname>A.P Simovic</surname>
          </string-name>
          ´, S. Babarogic´, and
          <string-name>
            <given-names>O.</given-names>
            <surname>Pantelic</surname>
          </string-name>
          <article-title>´. A domain-specific language for supporting event log extraction from ERP systems</article-title>
          . In ICCCC,
          <year>2018</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <given-names>M.S.</given-names>
            <surname>Uysal</surname>
          </string-name>
          ,
          <string-name>
            <surname>S.J. van Zelst</surname>
          </string-name>
          ,
          <string-name>
            <given-names>T.</given-names>
            <surname>Brockhoff</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Farhang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Pourbafrani</surname>
          </string-name>
          ,
          <string-name>
            <given-names>R.</given-names>
            <surname>Schumacher</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Junglas</surname>
          </string-name>
          , G. Schuh, and
          <string-name>
            <surname>W.M.P. van der Aalst.</surname>
          </string-name>
          <article-title>Process mining for production processes in the automotive industry</article-title>
          .
          <source>In Industry Forum at BPM</source>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <surname>W.M.P. van der Aalst</surname>
            and
            <given-names>A.</given-names>
          </string-name>
          <string-name>
            <surname>Berti</surname>
          </string-name>
          .
          <article-title>Discovering object-centric petri nets</article-title>
          .
          <source>Fundamenta Informaticae</source>
          ,
          <volume>175</volume>
          :
          <fpage>1</fpage>
          -
          <lpage>40</lpage>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          [12]
          <string-name>
            <given-names>T.</given-names>
            <surname>Vogelgesang</surname>
          </string-name>
          and
          <string-name>
            <given-names>H.J.</given-names>
            <surname>Appelrath</surname>
          </string-name>
          .
          <article-title>Multidimensional process mining: A flexible analysis approach for health services research</article-title>
          .
          <source>In EDBT/ICDT</source>
          , pages
          <fpage>17</fpage>
          -
          <lpage>22</lpage>
          ,
          <year>2013</year>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>