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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Evaluation of an Approach for Teaching Formal Concept Analysis</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Martin Watmough</string-name>
          <email>martin.watmough@ciber.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Conceptual Structures Research Group, Communication and Computing Research Centre / Department of Computing, She eld Hallam University</institution>
          ,
          <country country="UK">UK</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper describes the evaluation of coursework set for nal year degree students designed to teach Formal Concept Analysis (FCA). The usefulness of this approach is discussed with respect to its application in future iterations of the coursework. The source data was the result of a simulation between competing student teams undertaken on a mainstream ERP system provided by the business software vendor SAP A.G. and using the ERPsim software provided by ERPsim Lab at HEC Montreal. The simulation generated data on which Business Intelligence (BI) is typically based and is representative of business activity. The data generated by the simulation exercise was not speci cally for FCA, thus it provides a meaningful test of FCA in BI.</p>
      </abstract>
      <kwd-group>
        <kwd>Formal Concept Analysis</kwd>
        <kwd>FCA</kwd>
        <kwd>Enterprise Resource Planning</kwd>
        <kwd>ERP</kwd>
        <kwd>Business Intelligence</kwd>
        <kwd>ERPSim</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>This paper describes the evaluation of coursework set for nal year degree
students designed to teach Formal Concept Analysis (FCA). The assessment applied
a set of FCA tools and conventional Business Intelligence (BI) using graphical
or statistical methods in Microsoft O ce Software. There were to distinct
objectives to this activity, rstly to ful l the students learning objectives and secondly
to support an action research project about the application of FCA within
Enterprise Resource Planning (ERP) systems. The ful lment of the learning activity
was assessed in two ways, rstly as a comparison between the use of
conventional BI analysis and FCA tools and secondly as a comparison of FCA against
established theory. Topics for the action research project are highlighted in the
conclusions and further work sections, however, this is not the primary focus of
this paper.</p>
      <p>
        FCA is mathematical theory of data analysis using formal contents and
concept lattices [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] and has the potential to compliment and advance
current forms of analysis.
      </p>
      <p>
        The rationale for selecting this research is due to the demands being placed
on BI systems to improve and the di culties in identifying semantic data. A
simple de nition is "semantics = data + behaviour" [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. This suggests that
if the semantic content can be identi ed it may be possible to understand or
determine behaviour.
      </p>
      <p>
        The coursework is described in more detail later, however the principle is
to introduce frameworks and techniques for representing and reasoning with
knowledge for smart applications [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. The principle of the coursework is to
compare how analysis using tools such as Microsoft Excel compares to a FCA
tool set using data generated through the realistic use of an ERP system. The
students entered into the analysis with a practical knowledge of the processes
that generated the data set but having performed no analysis or re ection on
the impact of decisions made during the simulation.
      </p>
      <p>
        The need for analysis and decision making within enterprises is not new but
competition and complexity do combine to make the task vast and di cult to
execute e ciently or accurately. Business Intelligence (BI) is frequently used to
support analysis and decision making and can be traced back at least as far as
1958 [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], however, it remains a eld that is subject to much ongoing research
and development. Gartner [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] predicts that business units will control at least
40 per cent of the total budget for BI, a reason cited for this is that a signi cant
percentage of companies regularly fail to makie insightful decisions about their
business and markets. This implies that tools must be suitable for non technical
users while encompassing the reliability and exibility for application in modern
environments.
      </p>
      <p>ERP systems are essentially transactional systems that support a vast
array of business functions within the majority of organisations that exist today.
They are designed to be explicit and accurate in terms of control and data but
often lack the analysis tools and communication methods to support all of an
organisation's functions. This is where complimentary tools have a role to play.</p>
      <p>
        ERP systems support integration and control across various functional areas
of a company, therefore supporting the achievement of the company's plans [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
This makes them an excellent source of raw data in a relatively well de ned
format and structure, however the volume and granularity of the data make
analysis ine cient or inadequate without the application of BI tools.
      </p>
      <p>
        CUBIST [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] argues that the complexity of BI tools is the biggest barrier to
successful analysis, particularly because they do not work with the meaning of
data (semantics) and are not capable of e ectively handling unstructured and
structured data.
      </p>
      <p>
        In this speci c example the source data was the result of a game between
competing student teams undertaken on a mainstream ERP system provided
by the business software vendor SAP A.G. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] and using the ERPsim software
provided by ERPsim Lab at HEC Montreal [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. The simulation generated data on
which Business Intelligence was performed. The data generated by the simulation
exercise represents typical business activity and is not speci cally for FCA, thus
it provides a meaningful test of FCA in BI from ERP data.
      </p>
      <p>ERPsim is based on SAP ECC 6.0 which is an ERP system capable of
supporting in this example logistics and nancial activities for a number of
competing companies. All sales, procurement, master data, inventory, marketing and
nancial transactions are captured real time in additional to a limited number
of reports to show sales, inventory, balance sheet and pro t and loss. These are
transaction based reports and o er no analysis without the application of further
tools.</p>
      <p>As an ERP system is e ectively a relational database with data held in
joined tables it is possible to extract data that contributed towards a goal via
a query. Therefore a query using the table relationships was able to extract
all the transactional data available that contributed towards the outcome. For
example all sales transactions within the time period could be found via the
connection from billing through the outbound shipments to the sales orders.
Correspondingly individual sales order pro t based on the materials cost price
could also be extracted.</p>
      <p>The chart in gure 1 provides an example of the input and output variables
plotted to highlight the relationships that can exist in the simulation game.
On the right hand side cumulative pro t and percentage pro t above cost per
sale are shown. Cost is indexed at 100%, therefore 105 equates to 5% pro t over
cost. On the left hand side days inventory cover and the percentage of sales price
attributable to marketing spend is shown. In summary the data could represent
a number of relationships including:
{ Increasing cumulative pro t has an inverse relationship with decreasing days
of inventory cover (how many days the stock will last given the sales forecast).
[Holding less stock will result in more pro t]
{ Increasing pro t has a direct relationship with increasing marketing spend.</p>
      <p>[Spending on marketing leads to more sales, therefore more pro t]
{ Increasing pro t has a direct relationship with increasing pro t per sale.</p>
      <p>[More pro table individual sales leads to higher overall pro t]
2</p>
    </sec>
    <sec id="sec-2">
      <title>Method</title>
      <p>
        The primary problem is how to analyse data and identify semantic data or
relationships from a generic transactional data set. The coursework addressed
three of the learning outcomes from the course [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]:
1. Describe the notion of representing and reasoning with knowledge for smart
applications.
2. Draw on one or more frameworks and techniques for representing and
reasoning with knowledge for smart applications.
3. Identify the practical use of software tools for developing smart applications.
      </p>
      <p>The scenario presented to the students was:</p>
      <p>Day</p>
      <p>Cost %
Profit
Days_cover
Marketing
Spend %</p>
      <p>You are performing the role of a business analyst who has been tasked with
analysing the performance of your ERP Water Company by understanding how
a) your decision-making and that of others has impacted the organisation and
b) identifying rules that could be used to help this decision making in the future.
You are also evaluating the method of analysis in order to re ne the approach
employed for future iterations of this process. It is therefore less the intention to
learn ERP; rather through this experience you will explore business intelligence
and the role that Formal Concept Analysis (FCA) might play in this context.</p>
      <p>The coursework had three main sections consisting of conventional BI, FCA
and Evaluation / Conclusions. The BI analysis would use MS Access and Excel in
order to familiarise the students with the data using tools that would already be
familiar and o er graphical analysis techniques that are common and taught at a
school level of mathematics. Secondly FCA tools are applied based on essentially
the same data with any calculated values added to support the analysis. This is
expected to be an iterative process in order to produce the best results possible
but the core section of the data extract should be stable and reusable. The nal
section is an evaluation of the two approaches and conclusions.</p>
      <p>It is acknowledged that the goal of both the BI and FCA approach is to
identify potentially the same relationships, this is deliberate in order to encourage
an understanding of the data using tools and techniques in applications such as
Line chart (2 variables) 100
Graph on graph comparisons 69
Cumulative and actual data charts 62
Detailed Focus with annotation. 46
Line chart (3 variables) 23
Pie chart 23
Data table 15
Pivot table 15
Summary table (annotated) 8
Use of trend lines 0</p>
      <p>Table 1. Methods Applied under BI
Excel that will be familiar and well supported with documentation and guides.
An understanding of the data and relationships was deemed necessary given the
students had no prior knowledge of ERP systems or an understanding of the
processes in operation.</p>
      <p>
        The tools set consists of ve key software packages: MS Access as a
mechanism for extracting data from the ERPSim SAP system and creating the initial
data le (CSV) for analysis, MS Excel and FCA tools including: FcaBedrock [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ],
In-close [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] and Concept Explorer [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
      </p>
      <p>The method selected was generally an experimental and iterative approach in
order to extract and analyse key data, gradually re ning the method to explore
the anticipated relationships and evaluate the capabilities of the tool set. The
aim was to supply a consistent set of data to the FCA tool set making it a
repeatable process.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Student Results</title>
      <p>The basic analysis methods applied across all the course work are shown in
Table 1 and 2 with a percentage occurrences. It is noted that the marking of the
coursework did take into account more than the range of techniques applied.</p>
      <p>A minority of students also attempted to identify rules that explicitly stated
relationships and could be reused in future iterations of the simulation.</p>
      <p>The average mark achieved was 57 % with a standard deviation of 15.3.</p>
      <p>Tables 3 and 4 contains a summary list of points made within the Evaluations
and Conclusions section of the coursework for BI and FCA respectively.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Discussion</title>
      <p>The initial reaction of the students was one of confusion in how to tackle the
coursework, this is re ected to a degree in Tables 1 and 2, these show that less
complex forms of analysis were prevalent in all work, for example line charts
with two variables, but relatively few progressed onto considering more complex
selections such as line charts with three variables. A little trial and error
coupled with con dence could have eliminated most problems, this could also be
supported better with guided examples attempting the coursework.</p>
      <p>The marking of the coursework produced a normal distribution of marks with
an unexpected enthusiasm for FCA although this was tempered by the di culties
in using the tool set. It is not surprising that they experienced di culties given
the di erence between the development e ort behind the FCA tool set and BI
tools from providers such as Microsoft. It could be surmised that the students
understood the advantages of analysing large and relatively unstructured data
without expert knowledge or time consuming analysis. It would have been nice
to see the students experimenting more with the data and discovering or at least
looking for less obvious relationships.</p>
      <p>A consistent criticism of the FCA tool set, see table 4, was the di culty level
involved in data preparation and use of the tools. It would have been nice to
eliminate some of the repetitive tasks required by the exercise as the students
struggled to grasp and achieve a reusable data extraction mechanism, therefore
consuming time that could have been spent more productively on the analysis.
A problem that is not uncommon in real life applications.</p>
      <p>The presentations produced for assessment made it relatively easy to mark
however it was sometimes di cult to understand what was trying to be
communicated especially where annotations or additional notes were not present
or of low quality. The graphical nature of the presentation medium did form a
good basis for presenting the analysis and forced a summary rather than lengthy
descriptions of the process and mechanisms involved.</p>
      <p>It was clear from the conclusions in Tables 3 and 4 that an appreciation about
the di culties involved in delivering BI was achieved even from this relatively
small data set.</p>
      <p>The students really failed to identify data or relationships outside of the key
parameters, this is partially due to the data available as it was only a partial
extract of ERP systems. Even so there are many factors that could have been
o ered for consideration even if they could not directly be included in the
analysis. Examples of this could include the team structure or the decision making
of certain individuals being categorically better or worse in outcome to others.</p>
      <p>Graph on graph comparisons featured highly in the BI analysis, essentially
this included graphical comparisons that were either overlaid or annotated to
illustrate an event or relationship. Considering the frequency of this type of
analysis when it came down to the FCA tools set it was hardly applied, even
though the concept lattices are primarily a visual tool. The reasons for this were
not clear and possibly related to the di culty experienced in using the tool
set. This feature was not supported in the tool set but it was easily possible to
capture and present images side by side within the presentation.</p>
      <p>Discrete values proved much easier to understand than ranges, in order for
ranges to be understood manual input is required in order to create meaningful
sub ranges. Progressive scaling was applied but the de nition of the discrete
values was not appropriate to take advantage of this. With this in mind a
biordinal scale would be more useful when representing such values but this will
require a di erent approach when extracting the data or within FCA.</p>
      <p>As soon as the analysis required calculations to be performed it started to
face many of the challenges also faced by BI. Firstly there may be di erences in
the calculations between analysts, regions or indeed of interpretation. Secondly,
calculated gures and performance measures can lack scale. The analysis was
more successful when focus was given to a speci c attribute, this was achieved
by restricting the data being analysed. The down side of this was that it was a
manual process with relatively long iterations even though the source data set
did not alter. This limits the scope of data available and potentially the results
obtained which could be a signi cant disadvantage.</p>
      <p>
        It was clearly di cult to analyse the lattices unless a speci c feature was
chosen as the focus for the analysis, primarily due to their size and complexity.
A possible side e ect of focussing would be the accidental exclusion of data that
could highlight unknown or unexpected relationships which should have been
a major bene t for this type of analysis. The whole problem of visualising and
exploring or "concept exploration" as termed by Stumme [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] is proving to limit
the usefulness of this approach graphically at this time but alternative methods
of applying the results may be possible that either solve this issue or do not
require graphical representation.
      </p>
      <p>The analysis was limited as it only included attributes that could be
attributed to a strategic goal within the ERP system. Making the link within
relational database is relatively straight forwards however a far greater
challenge would be including data from sources with less well de ned relationships.
This maybe possible using tentative links such as times and dates but further
work is required. This could be achieved within the data extract query as applied
in MS Access for this approach.</p>
    </sec>
    <sec id="sec-5">
      <title>Review of Learning Outcomes</title>
      <p>Learning objective 1 - Describe the notion of representing and reasoning with
knowledge for smart applications. This was visible in the coursework by the use
of techniques such as performance measures / key performance indicators (KPI)
within the data extraction on graphical interrogation of the outcome.</p>
      <p>Learning objective 2 - Draw on one or more frameworks and techniques for
representing and reasoning with knowledge for smart applications. This was
visible in the coursework by the application of the tools and presentation of the
analysis in the form of the coursework. The range of techniques applied further
demonstrated the depth of analysis. There are a wide range techniques available
and a reasonable range have been applied but only the minority of students have
applied them.</p>
      <p>Learning objective 3 - Identify the practical use of software tools for
developing smart applications. This was visible in the coursework clearly by the
conclusions where the ability to interact with the analysis and discover relationships
was a clear advantage for FCA tools.</p>
      <p>An emergent learning outcome was with regard to a developed appreciation of
how the application of relatively simple analysis can highlight major aws in the
decision making processes employed during the game therefore resulting in poor
performance. A number of teams indicated this and identi ed where mistakes
had been made due to a lack of analysis or assumptions based on incomplete
knowledge.
6</p>
    </sec>
    <sec id="sec-6">
      <title>Conclusion</title>
      <p>The learning outcomes have been achieved with all students appreciating the
value and di culties associated with analysing ERP data. The results did re ect
a reasonable range of marks being awarded with all students able to perform both
BI and FCA over the data set provided.</p>
      <p>The di culty involved in data preparation had a signi cant impact on the
analysis performed, particularly with respect to the application of more
complex analysis techniques and semantic discovery. This was the main factor that
detracted from the learning outcomes.</p>
      <p>The coursework would bene t from more focus on the analysis and less e ort
required for the preparation of data. It is expected that signi cant manual input
will still be required in terms of de ning any calculations and manipulation of
graphical outputs.</p>
      <p>A structured criteria for the analysis techniques expected could lead to an
improvement in the marks awarded. This could include a pre-con gured solution
containing the basic forms of analysis, therefore forcing the use of more advanced
analysis methods as a minimum criteria for the coursework. This could be
achievable by reducing in the amount of data preparation activity required, however
this must not place a constraint on the experimental aspect of this coursework
and the ability to perform an open analysis.</p>
      <p>There is a continued value in applying two methods of analysis, the BI
approach is already familiar to the audience and clearly help understanding of the
data set. Applying purely an FCA approach would be very challenging at this
point in time.</p>
      <p>As part of the action research aspect a number of factors should be changed
for the next deployment of this coursework in order to permit the students to
progress towards more advanced use of FCA, this is detailed in Further Work.</p>
      <p>
        It was clear from the conclusions that the notion of applying BI and FCA was
understood and the value it has in real life applications. The value of good
analysis and the ability to evaluation unknown relationships was imparted. Equally
the potential for error, misunderstanding and potential lack of uptake because
of the complexity was clear and echoed the comments from Gartner in the
introduction with respect to what how analysis will be controlled by business units
and not technical experts [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
6.1
      </p>
      <p>Further Work
The further work section will contribute towards the action research agenda
and includes ideas or approaches to be included in the next iteration of the
coursework.</p>
      <p>A solution to reduce the amount of data preparation is required in order
to support a focus of more advanced FCA. The rst area for consideration is
providing a starting point that already supports the simpler forms of analysis.</p>
      <p>
        More advanced forms of analysis should be directly supported, this includes
utilising qualitative data, better visualisations such as lattice on lattice
comparisons and concept clustering with iceberg lattices [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] and di erent scaling
methods such as bi-ordinal. This is likely to impact the choice of tools selected.
      </p>
      <p>Utilising a solution that integrates directly to the data instead of the
restricted data set contained in the MS Access extract is de nitely a requirement
in order to support the forms of analysis highlighted above while providing a
mechanism for an iterative and experimental approach to nding relationships
within the data.</p>
    </sec>
  </body>
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