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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Third International Business Process Intelligence Challenge (BPIC'13): Volvo IT Belgium VINST</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Seppe K.L.M. vanden Broucke</string-name>
          <email>seppe.vandenbroucke@kuleuven.be</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jan Vanthienen</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Bart Baesens</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Decision Sciences and Information Management, KU Leuven Naamsestraat 69</institution>
          ,
          <addr-line>B-3000 Leuven</addr-line>
          ,
          <country country="BE">Belgium</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Management, University of Southampton Higheld Southampton</institution>
          ,
          <addr-line>SO17 1BJ</addr-line>
          ,
          <country country="UK">United Kingdom</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2013</year>
      </pub-date>
      <abstract>
        <p>For the Third International Business Process Intelligence Challenge (BPIC'13), a collection of real-life event logs from Volvo IT Belgium is analyzed. The provided logs contain events from an incident and problem handling system which is called VINST. This report presents results related to the following investigations. First, an openminded exploratory analysis of the given event logs and second, answering the four specic questions posed by the process owner. To do so, we utilize both already existing as well as dedicated developed tools, and heavily combine traditional data analysis tools and process-oriented techniques; we indicate the existence of a gap between these two categories of tools and as such emphasize the importance of a hybrid approach in a process intelligence context throughout the report.</p>
      </abstract>
      <kwd-group>
        <kwd>process mining</kwd>
        <kwd>process analysis</kwd>
        <kwd>data analysis</kwd>
        <kwd>process intelligence</kwd>
        <kwd>challenge</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>1.1 Overview
This report presents the results we have uncovered related to the analysis of the
Volvo IT data set in the context of the Third International Business Process
Intelligence Challenge (BPIC’13). The data set consists of three real-life event
logs from an incident and problem handling system called VINST.</p>
      <p>
        The report is structured as follows. First, a high level overview of the data set
and the VINST system is provided in Section 2, to familiarize readers with the
provided material. Next, in Section 3, we perform an open-minded exploratory
analysis using ProM1 [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] and Disco2 in order to get an initial idea about the event
1 ProM is an extensible process mining framework for the discovery and analysis of
process models and event logs. See http://www.processmining.org for more
information.
2 Disco is a commercial process discovery tool developed by Fluxicon and
provides an easy-to-use interface together with extensive ltering capabilities. See
http://uxicon.com/disco/ for more information.
logs’ composition and the VINST processes before moving on to answering the
questions posed by the process owner in Section 4. The report is concluded in
Section 5.
1.2 Methodology
We will make heavy use of both traditional data analysis tools and
processoriented techniques. We believe there to be a gap between these two categories
of tools, causing diculties when ltering, exploring and analyzing event based
data sets. Reports submitted to previous BPI challenges, for instance, illustrate
that practitioners and academics alike frequently perform initial ltering steps
using spreadsheet or OLAP-based tools. Oftentimes, the same tools are used to
derive descriptive statistics, before moving on to a more process-oriented view
(e.g. process discovery or performance analysis), which these traditional data
analysis tools lack. Since event logs are often handled as a large at table (i.e.
a listing of events), it is dicult to derive statistical information at the trace
level (i.e. a grouping of events) rather than at the event level. Filtering out
events based on complex control-ow based criteria is even more challenging.
Consider for example the user trying to lter out all events belonging to a trace
where two activities occur in parallel.
      </p>
      <p>Vice versa, tools which are specically geared towards the analysis of process
based data are often lacking in terms of ltering or descriptive statistics. Consider
ProM, for example, which contains a plethora of plugins for the discovery of
process models alone, but does not provide strong methods to lter or explore
the data set at hand. In ProM 6, only two helpful ltering plugins are provided
by default:
Filter Log using Simple Heuristics, which allows to discard events based on
their classication and traces based on their start/ending/contained events;
Filter Log by Attributes, which is able to lter on traces containing events
with a specic attribute-value pair. Advanced ltering options (e.g. value
greater than x) are not provided.</p>
      <p>The same can be said for plugins providing descriptive statics. Information about
events per case, number of cases and events and other simple counts are easily
retrieved, but no robust options are provided to derive other, more complex
event data.</p>
      <p>
        Due to the mismatch described above, practitioners and researchers currently
often nd themselves using an abundance of tools to perform their analysis tasks.
While this is not an insurmountable problem, of course, the fact remains that
available tooling towards the analysis of event logs can be improved. In fact,
this is one of the challenges also listed in the process mining manifesto [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Disco
stands out as a great contender, however, which has enabled practitioners and
researcher to quickly lter and inspect event logs, but as we will indicate later
on is not completely up to par with traditional data analysis tools when it
comes to inspecting particular attribute distributions or correlations. Therefore,
we will apply a hybrid approach in this report, switching back-and-forth between
(mainly) R and Disco to perform the desired tasks and combine statistical data
analysis with process mining insights.
      </p>
      <p>As a summary, Table 1 provides an overview of the dierences between
traditional data analysis tools and process oriented techniques. The main dierences
arise due to a dierent starting viewpoint on the data at hand. Traditional tools
work with at data tables containing record lines, whereas process oriented
techniques are aware of the hierarchical nature between cases and events.</p>
      <p>
        Other than the plethora of tools already available for (statistical) data
analysis and process mining, it should be mentioned that some work has also been
undertaken in order to add some process awareness or, more precisely, sequence
awareness to data analysis tools. TraMineR, for instance, is an R package [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]
for mining, describing and visualizing sequences of states, but contains support
for event (i.e. transition) based data sets as well, such as found in business
process event logs. The package oers a robust toolkit, but requires a relatively
large amount of user expertise to use correctly. Furthermore, ltering data sets
is somewhat dicult and the provided visualization options do not aim to
discover a summarized process map from the given sequences. Many authors have
also emphasized the need for sequential data support in traditional data base
management systems [46]. One particular example of interest is SQL-TS [79],
an extension for SQL which provides a simple extension for SQL to work with
sequential patterns, using proposed CLUSTER BY and SEQUENCY BY
clauses. This would provide a good starting point towards analyzing event based
data sets. I.e. the CLUSTER BY clause indicates the eld specifying the case
identier (e.g. SR Number), while the SEQUENCE BY clause indicates the
ordering of events. Sadly, two drawbacks exists which makes this approach not
yet fully suited for analyzing business processes. First, higher level structural
behavior, such as loops and parallelism, is not discovered and can thus not be
taken into account when constructing queries, or must be specied manually by
the user (i.e. explicitly take into account all parallel orderings possible). Second,
the language is not available for public use. Finally, we are also reminded of
regular expressions [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] (or regular languages) and other expressive grammar
languages such as linear temporal logic [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] (LTL) which are converted to
automatons to support the querying of sequence based data. Again, these tools
oer theoretically sound solutions to search sequence based data sets, but also
require some more advanced user expertise and or not able to deal with higher
level control-ow abstractions, so that they are quite far distanced from the
easy-to-use traditional and common tools oer.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2 Data Set Overview</title>
      <p>The BPIC’13 data set is obtained from Volvo IT Belgium and contains events
pertaining to an internally developed Siebel-based incident and problem
management system called VINST. Three log les are provided: one for incidents,
one for open problems and one for closed problems 3.</p>
      <p>The incident management process aims to restore normal service operations
after the occurrence of a specic incident within SLA dened boundaries.
Incident cases are rst handled by a rst line desk (the service desk and help
desks) and escalated to second line and third line teams when the rst line
workers are not able to resolve the incident. Incident cases are assigned a
priority level, which is calculated based on the impact (major, high, medium or low)
and urgency (high, medium, low) of the issue, see Table 2.
3 DOI identiers for the data sets are:
doi:10.4121/500573e6-accc-4b0c9576-aa5468b10cee, doi:10.4121/3537c19d-6c64-4b1d-815d-915ab0e479da and
doi:10.4121/c2c3b154-ab26-4b31-a0e8-8f2350ddac11.</p>
      <p>The problem management process tries to uncover the root causes behind
incidents and implement xes to prevent the occurrence of further incidents
in IT-services operated by Volvo IT and includes activities to update internal
knowledge bases with discovered ndings. This process is primarily handled by
second and third line teams. Contrary to the incident management process, there
is no push to front system implemented for the problem management process
which escalates cases among dierent service lines. The problem management
and incident management processes thus work in parallel, where incidents are
resolved as quickly as possibly in a reactive manner while the underlying root
cause is xed by a problem management case. These two workows are
supported by the Volvo IT VINST tool. The tool also supports other workow
processes such as handle questions and major incident procedure , but these are
not incorporated in the BPI challenge data set.</p>
      <p>The data set lists the following attributes for each logged event line:
Next section describes an exploratory analysis of the three event logs.</p>
    </sec>
    <sec id="sec-3">
      <title>3 Exploratory Analysis</title>
      <p>3.1 Descriptive Statistics
Using ProM and Disco, we perform some initial analysis on the given three event
logs. Some rudimentary, process based descriptive statistics are listed in Table
3. We use the default classier as stored in the event logs to classify events to a
set of activities, namely the combination of Status and Sub Status attribute
elds. For each event log, the total number of cases and events is listed, together
with the number of distinct cases (the dierent variants). Next, the total number
of event classes found in the event log, together with how many of these appear
as the rst or last activity in the traces contained in the event log is shown.
Finally, Table 3 also lists the minimum, average and maximum case length (i.e.
number of events).</p>
      <p>Especially for the incidents event log, the numbers indicate a large amount
of variability. As shown by Fig. 1, a large number of trace variants exist which
occur only once in the event log, leading to a skewed distribution in the number of
cases for each variant. Next, table 4 shows an overview of the dierent attributes
(described above) with their number of values and mean of frequencies of the
values for the three event logs.</p>
      <p>Let us now take a look at some performance related characteristics for the
given event logs. When we plot the mean duration for the cases represented by
a variant against the number of cases itself, a relation can be observed between
the rarity of a trace variant and its running time, as depicted by Fig. 2a. One is
free to remove these peculiar traces from the data set before continuing on with
further analysis, we but choose to leave these exceptional cases alone for now. A
similar observation can be made when plotting the case duration for all cases,
for example as shown in Fig. 2b for the incidents log. Observe that a small
number of cases exists which run for a high amount of time, with the longest
trace taking 2.11 years.</p>
      <p>Variants</p>
      <p>Next, Fig. 3 inspects the relationship between a case’s duration and the
involved product or impact level of the case. We observe that there exists a
strong correlation between the product a case relates to and the required running
time for that case. Indeed, this is to be expected, as is seems reasonable to
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Nr. of Cases</p>
      <p>1500
(a) Scatter plot showing the mean
duration in days for each variant against its
number of occurrences. Many exceptional
variants also exhibit a long duration.</p>
      <p>Variants
(b) Case durations (shown in days) for all
cases included in the event log.
assume that some products (such as PROD507, PROD34 and PROD681
highlighted in Fig. 3) lead to incidents which are harder to resolve, due for
example to the complexity of the product. Concerning impact levels, the box
plots shown in Fig. 3 do not immediately reveal a great dierence in duration
medians, although there does exist a signicant dierence between the mean
durations over the impact levels (which are 9.7, 13.7. 16.2 and 8.3 days for
Low, Medium, High and Major impact respectively).</p>
      <p>We can also derive performance related statistics for the support team
member (Owner First Name) and countries (Owner Country). However, contrary
to products, support teams and member are event-attributes, and can thus vary
within a case. When we would group traces as done above (e.g. a trace belongs
to the group associated to Sam when one of its events was executed by Sam),
this would lead to a skewed distribution as perhaps only one event in a long
trace was executed by a certain support team member. We are thus interested
in knowing the duration of certain tasks executed by the various support team
members, rather than the duration of the whole case.</p>
      <p>Sadly, the provided event logs do not contain starting and stopping times for
each activity. Instead, activities are logged as atomic events, i.e. only with a single
time stamp, and are assumed to have a duration of zero (instant completion).
Still, when relating task durations to support team members, we nevertheless
would like to have some idea about how long the case was being handled by a
certain person before moving on to the next activity (and, perhaps, some other
support team member). Therefore, we apply a simple pre-processing step where
we assign a completion time to each event equal to the (starting) time stamp
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      <sec id="sec-3-1">
        <title>PROD507</title>
      </sec>
      <sec id="sec-3-2">
        <title>PROD34 PROD681</title>
        <p>(b) Box plots depicting case duration
statistics per impact level. Although no
strong dierence among the medians
(shown by the box plots) becomes
apparent, the variance decreases for higher
impact levels. The means of the dierent
impact levels also signicantly dier at the
95% condence level.
of the event following directly after in the same trace. If there is no such event,
we just set the completion time equal to the starting time and assume this nal
event was instantly completed. This allows us to derive how long a particular
case stayed with a particular activity, and hence, support team member 4. Once
done, we can easily extract various sorts of information for the support team
members and countries. Table 5 provides an overview of mean activity durations
for activities, support team members and support team countries, as well as a
task-originator matrix for the support team members.</p>
        <p>As always, these initial exploratory results must be carefully interpreted to
avoid reaching to erroneous conclusions. The common warning given when
dealing with performance-originator oriented statistics indeed states that the fact
that someone is taking longer to do their job might simply be because this
worker commonly deals with harder jobs which take longer to resolve.
Additionally, using the mean duration may lead to misleading results under skewed
distributions; for example, the median duration for Anne Claire’s activities is
a just a few seconds. The standard deviation for the workers with high mean
4 Note that we assume the time stamp present in the logs to denote the starting time
of a particular activity. Only when this activity is completed does the next event
start.
shown.</p>
        <sec id="sec-3-2-1">
          <title>Anne Claire</title>
        </sec>
        <sec id="sec-3-2-2">
          <title>Earl</title>
        </sec>
        <sec id="sec-3-2-3">
          <title>Mica</title>
        </sec>
        <sec id="sec-3-2-4">
          <title>Elaine Ray</title>
        </sec>
        <sec id="sec-3-2-5">
          <title>Cincellia</title>
        </sec>
        <sec id="sec-3-2-6">
          <title>Bozidar</title>
        </sec>
        <sec id="sec-3-2-7">
          <title>Lucas</title>
        </sec>
        <sec id="sec-3-2-8">
          <title>Brice</title>
        </sec>
        <sec id="sec-3-2-9">
          <title>Minkyu</title>
          <p>activities for the incidents event log.</p>
          <p>(a) Mean activity durations for all activities based on
derived completion times. Again, Status plus Sub
Status is used as a classier to construct activities.</p>
          <p>Activity
Accepted/Wait - Vendor
Accepted/Wait - Implementation
Accepted/Wait - Customer
Completed/Resolved
Accepted/Wait - User
Accepted/Wait
Accepted/Assigned
Queued/Awaiting Assignment
Accepted/In Progress
Completed/In Call
Completed/Closed
Unmatched/Unmatched
Completed/Cancelled</p>
          <p>Mean
Duration
(Hours)
members are shown, sorted by the number of activities executed (summed last row).
Queued/Awaiting Assignment
Accepted/Assigned
Accepted/In Progress
Accepted/Wait
Accepted/Wait - Implementation
Accepted/Wait - User
Accepted/Wait - Vendor
Accepted/Wait - Customer
Completed/Cancelled
Completed/Resolved
Completed/In Call
Completed/Closed
Unmatched/Unmatched
Sum
durations is high, caused by a few (or even just one) activities taking a long time
to be passed forward. This is evidenced by Fig. 4, which shows a small number
of activities with a very high duration (i.e. more than one year). The process
owner can inspect these activities and the cases they belong to in order to verify
if further action should be undertaken. Furthermore, keep in mind that we have
derived activity durations based on a single time stamp present in the log les,
which might dier from the actual work time.</p>
          <p>Activities</p>
          <p>
            We limit the statistical description to the overview provided above, as not
to consume too much space. Nevertheless, this section illustrates the power of
using simple, at data oriented tools already widely available to get a rst,
solid introspection in the performance and characteristics of running processes.
However, since these tools lack a process oriented perspective, it is dicult to
derive statistical information at the trace level (a grouping of events) rather
than at the event level, as was already encountered in this section. This already
emphasizes the need for a hybrid approach. Therefore, we also briey explore
the data set using process specic tools, namely ProM and Disco.
3.2 Process Mining
Mining the incidents event log using HeuristicsMiner [
            <xref ref-type="bibr" rid="ref12">12</xref>
            ] in ProM yields a
result as depicted in Fig. 5, i.e. a spaghetti like model where all activities
appear to be connected with one another. Using Disco with all activities and
paths visible gives a similar (albeit prettier) outcome.
vanden
          </p>
          <p>Broucke
et</p>
          <p>al.
(a)
use
the</p>
          <p>Mo del mined with HeuristicsMiner in
a custom created plugin which allows
graph annotations).</p>
          <p>ProM (we
to provide
12
2
120
3
1 90
5704</p>
          <p>Complet d/Closed
5716</p>
          <p>5 Unmatched5/Unmatched
(c) The same mo del mined with a custom built pro cess discovery
to ol, which runs on top of Pandas (another statistical data
analysis to ol; see http://pandas.pydata.org) and extracts pro cess ows
together with summarizing metrics from a at event table. This
is then exp orted to a pro cess graph (using Graphviz). This
illustrates that the integration of pro cess-oriented p ersp ectives within
traditional statistical to ols is indeed p ossible.</p>
          <p>Let us see whether we can derive a straight-through process, a simple
process map explaining the multitude of behavior found in the event log. Filtering
on the frequent variants provides a solid means to do so. Fig. 6 shows the
process map derived from the ve most frequent variants, accounting for 41% of all
traces in the incident log.</p>
          <p>300
2828
Accepted/In Progress</p>
          <p>6511
555
855</p>
          <p>203
Queued/Awaiting Assignment
855</p>
          <p>Accepted/Wait - User
203
2828
1176
203</p>
          <p>When we just use the Status attribute as a classier, the resulting
process model becomes even simpler, and just shows all transitions between the
Accepted, Queued, Completed and Unmatched statuses, see Fig. 7.</p>
          <p>Since the process described a ticket based issue handling system, and since the
event logs do not contain start and ending times by itself (unless approximated
with a pre-processing step as done above), we can assume that the process does
not contain any parallel behavior, i.e. process case is passed on from one activity
to the next, without an activity create two or more concurrent ows of work.
That said, it is thus possible to view the process as a Markov chain, i.e. as
shown in Fig. 8 (once more using both Status and Sub Status elds), similar
Accepted
40117</p>
          <p>21713
to the process maps obtained by Disco, the depicted graph is also able to quickly
highlight the most important ows from one activity to the next.</p>
          <p>We can also easily show some initial performance focused process maps. Fig. 9
depicts the maximum and mean waiting times between activity occurrences. Note
the discrepancy between the mean duration and the maximum duration, also
indicating the presence of low-frequent exceptional cases which run far longer.</p>
          <p>Queued/Awaiting Assignment
instant</p>
          <p>Queued/Awaiting Assignment</p>
          <p>instant
8.3 hrs 67.7 mins</p>
          <p>One can continue to apply various other lters and views in order to extract
additional process maps. Fig. 10, for instance, shows the process map obtained
for the incidents log after ltering on performance (keep only quickest 95% of
cases, i.e. taking less than about one month), endpoints (cases should start with
either a Accepted or Queued activity and end with Completed), time frame
(rst of January 2012 onwards), and variation (use only cases whose sequence
of activities is shared by at least two cases). The process map is quite readable
and easy to interpret, but does not help further towards gaining more insights,
which requires rst stating the goals and questions one wants to investigate. We
will do so in the following section.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4 Answering the Process Owner’s Questions</title>
      <p>This section explores the questions posed by the process owner in the context of
the BPI challenge. Four broad questions were outlined, which will be dealt with
accordingly in the following subsections.
4.1 Question 1: Push to Front
This question only applies to the incidents event log. In this process, a strategy
is put in place which states that most of the incidents should be resolved by the
rst line support teams. The process owner is interested in knowing how many
(and which) cases escalate to a second or third team.</p>
      <p>The provided case description is somewhat ambiguous concerning which
criteria exactly determine whether an event was executed by a rst line team. It
is stated that The second line could be a support team within Org line C or a
support team working with Org line A2. This might lead one to believe that
all teams not belonging to either Org line C or Org line A2 are the rst
line teams. However, inspecting the Involved ST eld in the data set includes
names such as V5 3rd and V13 2nd 3rd, which leads us to believe that the
level assignment is included in this moniker. Therefore, we will add an extra
eld to the data set. Support team names including the strings 2nd or 3rd
will be regarded as an above rst level team (second, third or both). Names not
including such string shall be regarded as rst level teams.</p>
      <p>Next, we import the data set in Disco, but specify the Involved ST as the
activity and derive the following case counts:
7554 cases in total, creating an unstructured model.
4782 cases exist (63%) which did not require intervention from a second or
third line support team. This is obtained by applying an attribute lter.
2772 cases (the others) did pass through a higher level team.
704 of these cases even immediately start in a higher level.
556 cases start and stay within higher level teams during their complete life
cycle. This is a peculiar result. Fig. 11 shows the three most involved support
teams (all paths shown) where this happens.</p>
      <p>For what products is the push to front mechanism most used? We
export the cases found with Disco and turn to R to answer the posed
subquestions. After some straightforward operations, we derive for each product
the number of times the product got involved in a case passing through a higher
level support team. Fig. 12 shows a scatter plot showing the number of cases
each product was involved in for which the case did not go through second or
third level support teams (blue color) or did escalate to second or third level
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frame, performance and variants. Activities with an absolute frequency less than
a thousand are ltered out as well. All paths are retained.
support teams (red color). We can indeed notice some products being escalated
frequently to higher levels. Table 6 shows the twenty products with the highest
number of cases with second or third level support team involvement, together
with the number of cases without escalation.</p>
      <p>What is the impact of incident escalation on performance? We did
not nd a clear relationship between mean duration for all cases relating to a
certain product and the number of times the product was involved in a case
escalated to second or third level support teams (or not involved). However,
there is a signicant dierence in means of case durations for products which
were never involved in an escalated case and product which were (8.6 versus 16.5
days). There also exists a signicant dierence in means of case durations for
cases pushed to second/third level teams and cases that did not, i.e.: an average
case duration of 20.5 days versus 7.2 days. Avoiding higher level escalation is
thus indeed an important goal to be maintained.</p>
      <p>We have also inspected the impact of escalated incident cases on the duration
of problem handling cases, as the case states that cases ending up in second or
third line support teams disturbs them from doing their core activity (which
is generally not support) and that handling problem cases are primarily the
responsibility of 2nd and 3rd line support teams. It might thus be interesting
to see if we can nd a correlation between the performance of second and third
line teams in the problem handling process (one of their main tasks) and the
number of active escalated incident cases (which disturb them). Fig. 13 shows
the resulting outcome. The thick lines represent the number of cases over time
(all incident cases, escalated incident cases and problem cases both open and
closes), whereas the dotted lines show the mean and median duration of problem
cases active in the same time window. No signicant correlation can be derived.
This might be due to the data set (incident cases arrive neatly over time but
s
se 0
a 0
fC 3
o
r
eb 00
m 2
u
N
0
0
5
0
0
4
0
0
1
0
Product</p>
      <p>Products
almost always keep running until the middle of 2012). Also, in our analysis, cases
are seen as escalated even when they are not yet escalated at a specic point
in time (note however that this does not impact the median duration of problem
cases, which stays stable over time anyway). More data is needed to perform
a more rigorous analysis, or it might simply be that there exists no correlation
between these two specic properties.</p>
      <p>)sed )sy
rd a
un (D</p>
      <p>n
(H io
s t</p>
      <p>a
sea ru
0
6
0
5
0
4
0
3
0
1
0</p>
      <p>Active Incidents over Time
Active Excalated Incidents over Time
Active Problems over Time (Open and Closed)
Mean Duration of Problem Cases (Open and Closed)
Median Duration of Problem Cases (Open and Closed)
2010
2011
Time
2012
Fig. 13: Impact on number of escalated incident cases on duration of problem
cases over time.</p>
      <p>Where in the organization is the push to front process most
implemented, specically if we compare the Org line A2 with the Org line
C? What functions are most in line with the push to front process?
Finding out which organizational lines (or support teams or functional divisions)
were best able to deal with incidents without escalating them is non-trivial, as
these are event-related attributes and do not necessarily remain constant over
a complete case, so that deriving event based counts (e.g. with Disco) leads to
skewed distributions when cases contain varying number of events.</p>
      <p>For the organization lines A2 and C, we can apply an attribute lter to
retrieve the number of cases. Of the 2772 cases which were escalated to higher
level teams, 1298 of them were handled by Org line A2 at some point, whereas
1950 cases were handled by Org line C.</p>
      <p>For the involved support teams (and functional divisions), it is bothersome
to re-apply a lter for each dierent support team. Hence, we switch once more
to R. We aggregate all escalated and non-escalated cases by support team and
use the length of the unique list of Case IDs (SR Number) as the aggregation
function to get, for each support team, the number of cases the team was involved
in (for at least one activity) (only taking cases into account which escalated or
did not escalate to a higher level team). We then order the teams based on
their relative frequency dierence between escalated and non escalated cases to
account for the dierent number of cases. Table 7 shows the resulting overviews.
An overview for organization lines was included once more. Note the absence
of Org line C is this listing: although this line handled 1950 cases which were
escalated, the organization also handled 4176 cases which were not escalated, so
that this organization is dropped after deriving the relative frequency dierence.
4.2 Question 2: Ping Pong Behavior
The case description states: It occurs that support teams start to send incidents
to each other again and again (ping pong) which of course is an unwanted
situation. The business owner is interested in nding out about such cases. First,
we have to be clear about what exactly is meant with ping pong behavior:
The attribute of interest is the involved support team;
Ping pong is dened as a case starting with support team A, moving then to
another support team B (ping) and nally coming back to A later on (pong).
For example, we will consider the following support team trajectory as being
acceptable: hA; B; C; Di, although many support teams are involved, while the
following is not: hA; B; C; A; Di.</p>
      <p>No information about status requirements are given. Note that it is
however possible to perform an additional check here, e.g. also require that the
Queued/Awaiting Assignment status is revisited again when switching
support teams.</p>
      <p>Let us start with investigating the incidents log. We rst lter out all cases
which stay with the same activity (here: the involved support team), by using
a Follower lter in Disco which allows any activity succession but requires
dierent values for each matched pair. This leaves us with 50% of the ping
cases (3820 cases). Next, we want to get the pong behavior (returning to a
previous support team). This is less easy to retrieve with Disco, as the follower
lter cannot be applied here. As such, we search for tandem repeats using R and
the following aggregation. We aggregate by Case ID (SR Number) and apply
a custom function to signpost cases containing tandem repeats. The method we
apply is a bit involved and further detailed in Listing 1. We nd 1258 cases with
ping pong behavior.</p>
      <p>We can then export these cases to Disco again for visual validation and
analysis. Fig. 14 shows a simplied process map containing the ping pong cases
with some support teams hidden but all paths shown. Back-and-forth ping pong
behavior is indeed clearly visible.</p>
      <p>(a) Organization lines.</p>
      <sec id="sec-4-1">
        <title>Nr. of Cases with</title>
        <p>Second or Third (%)
Level Involvement
1298 46.83%
408 14.72%
318 11.47%
85 3.07%
50 1.80%
37 1.33%
23 0.83%
13 0.47%
15 0.54%
5 0.18%</p>
      </sec>
      <sec id="sec-4-2">
        <title>Nr. of Cases with</title>
        <p>First Level (%)
Involvement Only
501 10.48%
219 4.58%
242 5.06%
41 0.86%
4 0.08%
32 0.67%
14 0.29%
4 0.08%
16 0.33%
4 0.08%
(b) Involved support team.</p>
        <p>
          Listing 1: Finding ping pong behavior.
# Assume the following trace with ping pong behavior
# ( return to b):
&gt; trace &lt;- c(’a ’, ’a ’, ’b ’, ’c ’, ’b ’, ’d ’)
# " Match " all elements equaling b:
&gt; match (c( trace ) , ’b ’, nomatch =0)
[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] 0 0 1 0 1 0
# Take the difference between elements :
&gt; diff ( match (c( trace ) , ’b ’, nomatch =0) )
[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] 0 1 -1 1 -1
# 0: stays at ’b ’, -1: leaves from ’b ’, 1: enters ’b ’
# We thus check if ’b ’ is ’entered ’ multiple times by finding
# elements equaling 1:
&gt; match ( diff ( match (c( trace ) , ’b ’, nomatch =0) ) ,
+ 1, nomatch =0)
[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] 0 1 0 1 0
# And summing :
&gt; sum ( match ( diff ( match (c( trace ) , ’b ’, nomatch =0) ) , 1,
+ nomatch =0) ) &gt; 1
[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] TRUE
# However , it could be that our trace starts with the element
# we ’ re finding a tandem repeat for , we thus create an
# artificial start event :
&gt; sum ( match ( diff ( match (c(’ __START__ ’, trace ) , ’b ’, nomatch =0)
) , 1, nomatch =0) ) &gt; 1
[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] TRUE
# We ’ ve only tested for ’b ’, but need to do
# so for each element :
&gt; lapply ( unique ( trace ) ,
+ function ( el ) {
+ sum ( match ( diff ( match (c(’ __START__ ’, trace ) , el ,
+ nomatch =0) ) , 1, nomatch =0) ) &gt; 1
+ }
+ )
[[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ]] [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] FALSE
[[
          <xref ref-type="bibr" rid="ref2">2</xref>
          ]] [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] TRUE
[[
          <xref ref-type="bibr" rid="ref3">3</xref>
          ]] [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] FALSE
[[
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]] [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] FALSE
# Summing : is there an element which is tandem repeating ?
&gt; sum ( unlist ( lapply ( unique ( trace ) ,
+ function ( el ) {
+ sum ( match ( diff ( match (c(’ __START__ ’, trace ) , el , nomatch
=0) ) , 1, nomatch =0) ) &gt; 1
+ }
+ ))) &gt; 0
&gt; [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] TRUE
1
89
85
1
122
2506
        </p>
        <p>226
16
58
G96
817
14
61
V51972nd
D4
1100
47
653
57</p>
        <p>572
92
96
123
D5
1408</p>
        <p>Is there a correlation between the ping pong behavior and the total
life time of an incident? Fig. 15 shows a scatter plot with case durations
separated by cases with (colored red) and without ping pong behavior (colored
blue). Contrary to the statement made in the case description, no signicant
correlation becomes apparent. A Welch Two Sample t-test conrms that the
means of 1.47 (ping pong) days and 1.35 days (no ping pong) are not signicantly
dierent at the 95% condence level.</p>
        <p>Table 8 summarizes the ndings of ping pong behavior for the three event
logs. Since the problem processes do not contain separate elds for the involved
support team and support team functional division, we have only used the latter
for these logs. We note that the relation between duration and ping pong
behavior is not so clear as it may appear at rst sight. For instance, we nd that closed
problems which do exhibit ping pong behavior are closed faster than those which
do not. One might suggest to inspect the correlation between case duration and
the number of ping pongs performed, but we did not nd any particular pattern
when doing so for the incidents log (using the number of support teams which
ping ponged out of the total support teams involved in the case).
What are the functions, organizations, support teams responsible for
most of the ping pong? What products are most aected by it? Due
to space limitations, we only include the results for the incidents log. The same
approach can be applied to the other logs. Again, we aggregate at the trace level,
rather than the event level to account for skewed results. Table 9 lists the ten
highest products, support teams, functional divisions and organization lines for
the cases containing ping pong behavior.</p>
        <p>)
s
y
a
D
(
n
o
i
t
a
r
u
D
0
0
5
0
0
4
0
0
3
0
0
2
0
0
1
0</p>
      </sec>
      <sec id="sec-4-3">
        <title>Nr. of Cases Nr. of Cases</title>
        <p>with with</p>
      </sec>
      <sec id="sec-4-4">
        <title>Ping Ping Pong</title>
      </sec>
      <sec id="sec-4-5">
        <title>Behavior Behavior 1258 1159 21</title>
        <p>Cases</p>
      </sec>
      <sec id="sec-4-6">
        <title>Signicant</title>
      </sec>
      <sec id="sec-4-7">
        <title>Mean Duration</title>
      </sec>
      <sec id="sec-4-8">
        <title>Dierence</title>
        <p>No (p-value: 0.10)
No (p-value: 0.31)
Yes (p-value: 0.00),
22 versus 3 days
4.3 Question 3: Wait User Abuse
The challenge case states: People try to nd workarounds that stop the clock
from ticking. One way of doing this is manually giving an incident the sub status
’wait user’. Although there are guidelines not to use this sub status, some people
are breaking this guideline.</p>
        <p>We again use the incidents log to inspect this behavior. We’re interested in
the Sub Status Wait - User, which only occurs together with the Accepted
main status. We can thus lter on this activity which results in 33% of the cases
containing the Accepted/Wait - User activity.</p>
        <p>Who is making most use of this sub status (action owner)? What is
the behavior per support team, function, organization etc? To delve
deeper into this behavior, we inspect how long cases stay within the
Accepted/Wait - User state before another state becomes active, and will correlate
this with other properties. Table 11 provides an overview of the ten support
team members having spent most time in the Wait - User state, ranked by
the median to account for exceptional outliers. Again, one should take care not
to derive conclusions too quickly. We could, for example, lter out owners such
as Susanne whose minimum duration does not exceed a certain threshold.
Alternatively and perhaps a better approach since we do not possess starting
and completions times of activities, we could also check for the absolute number
of times someone activated the Wait - User state, instead of inspecting the
duration. This provides the following list: Siebel, Pawel, Muthu, Brecht, Marcin,
Fredrik, Andreas, Katia, Krzysztof, Emil. Just as for the previous questions,
this count can also be aggregated at the case level. Follow-up questions by the
process owner can thus quickly result in more ne-tuned analysis.</p>
        <p>We close this question with Table 11, which provides an overview of the ten
highest support teams, functional divisions, organization lines, countries and
owners making most use of the Wait - User status, ordered by the number of
times the associated actor executed a Wait - User status transition.
4.4 Question 4: Process Conformity per Organization
This question pertains to Org line A2 and Org line C: In general the Volvo
IT organization is spread in two organizations: Org line A2 and Org line C. It
would be interesting to see how conform or how much in line every organization
is with the incident and problem management processes.</p>
        <p>This is an open-ended question for which more domain knowledge must be
gathered before it can be answered in a satisfactory way. The main question
is what is meant with in line. One particular perspective was already focused
upon when dealing with the rst question: which of these two organization lines
perform most case escalations to higher level support teams?</p>
        <p>When being in line is related to case duration, we can derive the mean case
durations for Org line A2 and Org line C respectively: 21 days versus 10 days
(for the incidents log). When SLA’s are set on total running time of case, the
outcome might, however, be dierent. Consider for example an SLA determining
that incident handling cases may take at most 7 days (one week). Now Org line
A2 violates this 1494 while Org line C performs worse: 3529.</p>
        <p>Finally, it is also possible to view in line conformance in terms of a
prescriptive process already in place. Ticketing based systems such as this one, however,
are not often subjected to such designed processes, as is also evidenced by the
unstructured nature of the full process map with no ltering applied. As a proof
of concept, however, let us assume a designed process as shown in Fig. 16. We
will only make use of Status transitions to allow for enough freedom for the
sake of this example. We assume that cases must start with an Accepted or
Queued status. Both these statuses can repeat, and it is possible to go from
one state to another as well. Finally, cases must be ended with a Completed
state following Accepted.</p>
        <p>Completed
Accepted</p>
        <p>Queued</p>
        <p>Fig. 16: An example designed prescriptive to-be process model.</p>
        <p>We load this model into ProM in order to perform control-ow based
conformance analysis. We use the alignment based conformance checking plugin by
Adriansyah et al. [1315]. Fig. 17 shows the results of the conformance analysis.
Inspecting the trace tness distributions (a measure of being in line with the
prescribed process), we can derive that Org line A2 is less conform (relatively)
than Org line C. Keep in mind, of course, that we have used an example model.
By comparing the as-is situation with the to-be model, it becomes possible
to implement changes in order to try to x problem areas.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5 Conclusions</title>
      <p>This report presented the results we uncovered related to the analysis of the
Volvo IT data set for the Third International Business Process Intelligence
Challenge (BPIC’13). An open-minded exploratory surveyance of the data set was
performed, followed with a deeper analysis towards answering the specic
questions posed by the process owner.</p>
      <p>
        To do so, we have applied both traditional data analysis tools and
processoriented techniques. As evidenced by this report, there exists a gap between
these two categories of tools, causing diculties when ltering, querying,
exploring and analyzing event based data sets, as is also put forward as one of the
challenges listed in the process mining manifesto [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Therefore, we have utilized
a hybrid approach, combining and switching back-and-forth between (mainly)
R and Disco.
(a) Trace tness distribution: Org
line A2.
(b) Trace tness distribution: Org
line C.
      </p>
      <p>(c) Aggregated overview highlighting conformance issues.</p>
      <p>Fig. 17: Conformance analysis results for Org line A2 on example process
model.</p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgment</title>
      <p>We would like to thank the KU Leuven research council for nancial support
under grand OT/10/010 and the Flemish Research Council for nancial support
under Odysseus grant B.0915.09. We thank VØronique Van Vlasselaer for her
insights regarding R.</p>
    </sec>
  </body>
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