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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Australian Bureau of Statistics Implementation of Semantic Web Technology</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Arupa Sarkar</string-name>
          <email>arupa.sakar@abs.gov.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michael Mecham</string-name>
          <email>michael.mecham@abs.gov.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Peter Meadows</string-name>
          <email>peter.meadows@abs.gov.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Australian Bureau of Statistics</institution>
          ,
          <country country="AU">Australia</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The ABS is Australia's official national statistical agency. The requirements for a Web Ontology tool were built from a wide consultation with stakeholders, internal communication experts, technical experts and external clients. The interest was driven from a desire to avoid the rapid decay of explanatory material as statistics and methods updated regularly. The primary focus of this project became a cost effective tool that could deliver a flexible product which could be updated regularly by operational staff. This meant something that could be derived from a complex statistical conceptual metadata such as the 2008 System of National Accounts and be progressively updated.</p>
      </abstract>
      <kwd-group>
        <kwd />
        <kwd>Semantic</kwd>
        <kwd>ontology</kwd>
        <kwd>official statistics</kwd>
        <kwd>documentation</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>This paper outlines the Australian Bureau of Statistics interest in harnessing the
data aggregation and organizational features offered by ontology technologies. ABS
business, goals, practical application and technical implementation are discussed.
ABS understands an ontology to be a formal, explicit specification of a shared
conceptualisation[1] for a domain of interest. An ontology provides a shared vocabulary,
which can be used to model a domain, that is, the type of objects and/or concepts that
exist, and their properties and relations</p>
    </sec>
    <sec id="sec-2">
      <title>Discussion of the Business Requirement and Ontological</title>
    </sec>
    <sec id="sec-3">
      <title>Benefits</title>
      <sec id="sec-3-1">
        <title>Business of the Australian Bureau of Statistics</title>
        <p>The ABS is Australia’s official national statistical agency. It was established over
100 years ago as the Commonwealth Bureau of Census and Statistics, following
enactment of the Census and Statistics Act 1905. The agency became the Australian
Bureau of Statistics in 1975 with the passing of the Australian Bureau of Statistics
Act 1975. This Act also established the role of the Australian Statistician and defined
the functions of the ABS.</p>
        <p>The ABS provides statistics on a wide range of economic, social, population and
environmental matters, covering government, business and the community. It also has
an important coordination function with respect to the statistical activities of other
official bodies, both in Australia and overseas.</p>
        <p>Economic statistics are produced predominantly from the ABS business survey
program. They include an extensive range of statistical outputs relating to the
structure and performance of the Australian economy. Population and social statistics are
produced mainly through the ABS household survey program. They include statistical
information relating to the Australian population, including census and demographic
statistics, as well as information relating to the social and economic wellbeing of the
population.</p>
        <p>The ABS develops national statistical standards, frameworks and methodologies,
which are applied, as appropriate, to all ABS statistical collections, including business
and household surveys. The ABS takes a leading role by encouraging other Australian
state and territory government agencies to adopt these standards, frameworks and
methodologies in their statistical activities. The ABS also works closely with other
agencies involved in the development of standards and frameworks. These standards
are developed and implemented on the basis of consultation and input from a range of
stakeholders and interest groups in the statistical and user community.</p>
        <p>One of the key methods for communicating with the user community is through the
use of Concepts, Sources and Methods (CSM) documentation. These documents,
usually large complex pieces of work, are produced irregularly and are intensive to
write and re-write. In 2008, the economic statistics part of the organisation decided on
the need for an improved means of creating these documents, plus open up the ability
for users to comment or discuss methods.
2.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>International conceptual frameworks</title>
        <p>An important consideration when preparing CSM documentation is that in order to
support comparability and assure quality of statistics internationally there are a range
of conceptual frameworks and standards which have been agreed globally and which
are updated over time as information needs evolve. Frameworks and standards for
various statistical domains (eg Labour, Economic Accounts) are registered in the
Global Inventory of Statistical Standards which is maintained by the UN[2]. The
System of National Accounts 2008 (2008 SNA)[3] is one example.</p>
        <p>Each nation needs to make decisions when implementing the global framework.
There exists, an Australian System of National Accounts (ASNA)[4] which is based
on SNA. ASNA identifies, for example, cases where Australian Accounting
Standards make it impractical to collect data for a concept on exactly the same basis as
defined in SNA. Instead data is compiled for a closely related concept as defined in
ASNA.</p>
        <p>The European system of national and regional accounts (ESA95) provides an
example of a transnational framework which is also consistent with (an earlier version
of) SNA[5].
2.3</p>
      </sec>
      <sec id="sec-3-3">
        <title>Rationale for a web ontology tool</title>
        <p>The rationale or requirements for a tool were built from a wide consultation
process. The main area of interest was driven from a desire to avoid the rapid decay of
explanatory material as statistics and methods are updated regularly. The primary
focus of the project became a cost effective tool that could deliver a flexible product
which could be updated regularly by operational staff. This meant something that
could be derived from a complex statistical conceptual metadata such as the 2008
System of National Accounts and be progressively updated as methods and data
changed.</p>
        <p>Some other external demands placed on a documentation tool included the ability
to browse, search and discover concepts. As the 2008 SNA is a linked set of economic
accounts, then the conceptual metadata needed to manage overlapping concepts and
should only be defined once and linked into the explanation of the account with the
ability to see where the concept was used in other parts of the National Accounts.</p>
        <p>A pragmatic decision was made in the early stages of developing requirements
around release of new material. It was considered not feasible to quality control new
explanatory information in each quarter so an annual process was suggested. This
added further requirements to have a staging and sign off environment prior to release
to the web.</p>
        <p>Internal demands for a systematic documentation tool added some requirements
such as the ability to have a corporate approach to a tool and looking for ways to link
the documentation in the future so there could be further sharing of metadata between
reporting areas. There was emphasis on a tool being compatible with the future
enterprise architecture of the ABS to avoid re-engineering in a future environment.
Another requirement was to increase usability by staff who would be responsible for
maintaining and updating documentation. Documentation is considered to be a burden
under current Notes/Office[6] product based environments. The Notes/Office
environment is considered to be poorly structured despite the versatility of Notes for
controlling documents.</p>
        <p>The impact of social media and web 2.0 was seen as a new playing field for the
recording of explanatory material. This generated an expectation of being able to hold
discussions and add comments to entries, though resources need for moderation were
of concern. A need to maintain a history of discussion and methods changes was
considered to be a part of the requirements, noting the need for transparency and the risk
of duplicating discussion or methods if not recorded.</p>
        <p>The ABS works with a secure environment policy for documentation that is
released to the web. There was a need for a secure environment to host, stage and to edit
documentation. There is also a need to have some governance arrangements over the
quality control and final sign off on components. It was recognised at the initial stages
that the first set of documentation would mean intensive sign off, but would be
minimal for updates once the tool was up and running.
3</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Objectives</title>
      <p>The primary objective was to allow complete traversal of a networked node
structure of Concepts, Sources and Methods for ABS purposes. This would permit a more
open and transparent view of ABS statistical techniques. From a technical
perspective, a semantic wiki would deliver numerous benefits and the potential for
extensibility. Secondary to this, was the need for pragmatic re-use of ABS metadata. Namely,
the underlying CSM ontological linkages underpinning the ASNA or economic
model. Achieving this would allow for smarter extensibility across numerous ABS
systems and their conceptual models. An example of extending systems reach driven by
CSM ontology reuse would be opening ABS documentation to public comment
through dynamic content driven web forums.
4</p>
    </sec>
    <sec id="sec-5">
      <title>Overview of business requirement</title>
      <p>The purpose of this project was to formulate, detail and define the process of
producing a new Australian System of National Accounts: Concepts, Sources and
Methods (CSM) to replace the current CSM published in 2000 by the Australian Bureau of
Statistics. The final output of this project was a new and improved CSM. Additionally
a new CSM was needed because the existing CSM was out-dated and needed to
comply with a new set of international standards released in 2008. In summary, a new
CSM was needed due to address a number of factors.</p>
      <p>The factors are:



changes to the system of national accounts and balance of payments;
user demand for a more interactive CSM; and
desire for new technology being available to maintain contemporary CSM
documentation by contributors;</p>
      <p>This project also sought to create a new CSM with richer feature set offering
improvements over the existing CSM. Initial analysis of client requirements was
followed by an Agile approach to object modeling of CSM, ensuring all-way linkages
were maintainable and traversable. OWL fitted this requirement and offered the
ability to be extended or modified. Semantic Works Media Wiki plugin was chosen and
integrated well with pre-existing wiki templates and again offered a reasonably simple
upgrade path for future needs.
5</p>
    </sec>
    <sec id="sec-6">
      <title>Establishing the project team</title>
      <p>In addressing the business objective “to allow complete traversal of a networked
node structure of Concepts, Sources and Methods”, use of ontologies, and related
tooling, appeared logical as the cornerstone for the solution. Suggested re-write: The
key business objective was to produce the publication “Australian National Accounts:
Concepts, Sources and Methods” (ABS cat. no. 5216.0). The logical solution was in
the use of ontologies and related tooling.</p>
      <p>ABS understands an ontology to be a formal, explicit specification of a shared
conceptualization[7] for a domain of interest. An ontology provides a shared
vocabulary, which can be used to model a domain, that is, the type of objects and/or concepts
that exist, and their properties and relations.</p>
      <p>The project, therefore, included a major component of R&amp;D (research and
development). As well as needing to address a specific set of business needs, the project
was seen as a potential forerunner to wider use of ontologies and related technologies
within the ABS. The project team consisted of a number of developers working
closely with subject matter experts in regard to economic statistics. ABS experts in R&amp;D
worked closely with the project team.The team undertook a range of research and
consultation in regard to product suites and international practices before
commencing their main development work.It worked to clarify and formalise the business
requirements. It then commenced cycles of object modeling followed by testing,
including business review.
6</p>
    </sec>
    <sec id="sec-7">
      <title>Technical constraints</title>
      <p>The original vision for the project, based on the business requirements, was that
Subject matter experts would be able to draft content within the ABS environment,
including relationships and versioning control.</p>
      <p>Appropriate content testing, review and approval processes would then occur
within the ABS with authorized processes.</p>
      <p>Content would then be released to the website in accordance with ABS
dissemination processes, standards and protocols.</p>
      <p>The aim, therefore, was a technical solution that integrated well with workflow
processes and common desktop applications within the ABS[8]. IBM Notes[9]
(Client) and IBM Domino[10] (Server) is used as groupware within the ABS. This
includes corporate content management roles fulfilled by products such as Microsoft
SharePoint in other organisations. IBM Connections[11] is used to support wikis and
related collaboration spaces within the ABS. In 2010, this suite of products from IBM
did not include plug-ins for defining, managing, publishing and using ontologies.1
The aim, therefore, became to establish a solution that would interoperate effectively
with the ABS groupware environment rather than being able to develop a solution that
was “native” to that environment. In regard to the architecture of the solution, there
would need to be an interface for definition and maintenance of ontologies; selection,
browsing and exporting features; and a canonical store for ontology and versions.
7
7.1</p>
    </sec>
    <sec id="sec-8">
      <title>Technical evaluations and selections</title>
      <sec id="sec-8-1">
        <title>Ontology plugins</title>
        <p>A range of ontology plugins, beyond the specific wiki functionality associated with
IBM Connections, were evaluated. These included Onto Wiki, Media Wiki and
Semantic MediaWiki.</p>
        <p>These plugins were found to perform adequately in their own right but did not
integrate in a viable manner with ABS’ internal authoring, approval and web publishing
environments.</p>
        <p>After initial evaluations, Semantic MediaWiki was chosen by the project team. This
selection followed several attempts at integrating semantic plugins within the ABS IT
environment, pragmatically Semantic MediaWiki was the easiest to configure. Factors
influencing this choice included: useability; search pattern result sets being better than
others; and, availability of expert resources.
1 The authors are unaware of ontology plugins having been added in the past three years but
have not undertaken detailed product research to confirm this remains the case.
7.2</p>
      </sec>
      <sec id="sec-8-2">
        <title>Conceptual Modelling</title>
        <p>Both Protégé and Altova SemanticWorks were used by the Project Team. Some
“hand editing” of RDF was also required at times.</p>
        <p>Protégé is a free, open source ontology editor and knowledge-base framework.
The platform supports modelling ontologies via a web client or a desktop client.
Protégé ontologies can be developed in a variety of formats including OWL, RDF(S), and
XML Schema.</p>
        <p>The project team used Protégé via desktop client to develop the ontology in OWL
format.</p>
        <p>SemanticWorks is the visual RDF/OWL editor from the creators of XMLSpy.
(The latter is used widely in the ABS for working with XML). It allows you to
graphically create and edit RDF instance documents, RDFS vocabularies, and OWL
ontologies with full syntax checking.</p>
        <sec id="sec-8-2-1">
          <title>SemanticWorks provided powerful, easy-to-use functionality for:</title>
          <p> Visual creation and editing of RDF, RDF Schema (RDFS), OWL Lite, OWL DL,
and OWL Full documents using an intuitive, visual interface and drag-and-drop
functionality
 Syntax checking to ensure conformance with the RDF/XML specifications
 Auto-generation and editing of RDF/XML or N-triples formats based on visual</p>
          <p>RDF/OWL design
 Printing the graphical RDF and OWL representations to create documentation</p>
          <p>SemanticWorks was found to be a relatively user friendly tool for working with
ontologies. It tended to be preferred to Protégé by subject matter experts but Protégé
was, in general, preferred by developers.</p>
          <p>Using OWL as the common representation, it proved viable to move content
between SemanticWorks and Protégé in both directions.</p>
          <p>Overall Protégé was used more widely by the project team. If ontologies were to
be developed and maintained more broadly by subject matter experts from across the
ABS in future, however, many of the more advanced capabilities of Protégé may not
be required (or understood) by many of the users. For such users they would
represent added complexity rather than added capabilities.</p>
          <p>No overall decision was made in regard to ongoing use of Protégé, SemanticWorks
or a third alternative for future work on developing ontologies within the ABS. The
longer term choice of tool would depend somewhat on
 who was responsible for developing ontologies (subject matter experts, or
developers advised by subject matter experts)
 requirements for content approval processes
 requirements for integration with other tools in the ABS desktop environment
7.3</p>
        </sec>
      </sec>
      <sec id="sec-8-3">
        <title>Infrastructure</title>
        <p>The tools being used by the project team could not be supported quickly and easily
within mainstream ABS development environments[13] in regard to repositories (eg
Oracle RDBMS, SQLServer) and coding (eg Java).</p>
        <p>Ultimately, a MySQL database was used to store the content and PHP was used for
scripting. This allowed a flexible approach to defining a large number (10,000’s) of
classes and their properties. It also allowed for better parent – child linkages and the
ability to deal with circular references.</p>
        <p>While the pressure to maintain momentum required that the team work outside the
mainstream development environment, this added to the challenges in than having the
content disseminated to the ABS web environment.
8</p>
      </sec>
    </sec>
    <sec id="sec-9">
      <title>The dissemination challenge</title>
      <p>Section 6 refers to approval processes for releasing content to the web, together
with standardisation of web architecture and of processes for transferring content
from internal repositories to the web.</p>
      <p>These processes and protocols are important elements in guaranteeing the
statistical quality, reliability and consistency of statistical products and services made
available to users by the ABS.</p>
      <p>These processes and protocols are, however, under increasing pressure to evolve
more quickly as dissemination needs, expectations and opportunities change. For
example, less than 20 years ago printed publications were the main focus for ABS
dissemination processes, now they are a negligible element of our output.</p>
      <p>While there are increasingly extensive user driven data services available from the
ABS currently, the majority of content on the ABS website in 2013 consists of
“static” products such as PDFs, Spreadsheets, Data Cubes and authored (rather than
dynamically generated) HTML pages.</p>
      <p>A major update to the dissemination strategy released in 2013 aims for a major
change in the balance between static products and data services in the next few years.
More extensive metadata services (eg to help external users code/define their own
data based on standard classifications/vocabularies published by the ABS) are also
expected.</p>
      <p>In 2013, the project might have been selected as an “early adopter” for the updated
dissemination strategy.</p>
      <p>In 2010 the fact that the architecture used for working with ontologies did not (and
could not) align with preferred ABS web architecture at that time proved to be a
critical barrier to the project becoming a model for further development, and
dissemination, of ontologies by the ABS.
9</p>
    </sec>
    <sec id="sec-10">
      <title>The outcomes</title>
      <p>This project confirmed that there are significant benefits from investing in an
inhouse semantic authoring tool for explanatory documentation that have a statistical
framework. The ability to transverse the linkages in the environment mean
improvements in access, development and sharing by staff. One of the barriers that still needs
to be reconciled and is worth considering for any National Statistical Office is the
existing process and maturity of web publishing systems. This is especially true in the
case of strict branding and desire for control of content.</p>
      <p>The project succeeded in a proof of concept for managing complex relationships
and was a start in the long journey of a consolidated metadata store for concepts. The
benefits of using an ontology demonstrate the ease in which a network of
relationships could be developed and overlain with significant amounts of documentation.
Staff satisfaction with the authoring tool was quite high, with some reservations about
security and the ability to migrate from an authoring to a web environment.</p>
      <p>The inability to readily integrate the content and the workflows with ABS
internally used groupware and with web architecture proved insurmountable barriers to
quickly and extensively “productionising” the outputs from the project.</p>
      <p>Some of the content developed during the project has been released to the web. For
example, the updated Concepts, Sources and Methods for Australian System of
National Accounts (ASNA) was released last year as a PDF[14] which comprises 722
pages. Content for the PDF was not extracted automatically from the ontology but
migrated manually.</p>
      <p>One of the key objectives of stakeholder interaction was not met due to the barrier
to publish in a semantic web format. The project may be renewed as the ABS reviews
its operational environment and develops new pathways for publishing information.</p>
    </sec>
    <sec id="sec-11">
      <title>Future Directions</title>
      <p>10.1</p>
      <sec id="sec-11-1">
        <title>Vision for expanding the original specifications</title>
        <p>As the project developed, there was wider recognition of the potential that the
solution based on Semantic MediaWiki and the ontology toolset could provide to clients.</p>
        <p>The business customer developed the following scenario as the project was being
completed:</p>
        <p>Imagine an operator on the economic accounts that could have a button to the
conceptual framework in which they were responsible for. Imagine that they could
examine the concept they were working on, any internal or external discussion or
unforeseen complexity they may not have been aware and the ability to see what
impacts will occur from changes they intend to make on their component as well as
recognising the changes that others will make on their source information. Now imagine
if they could seamlessly move into the detailed documentation need to exactly operate
the economic accounts system. Once finished with their component, then seamlessly
move onto reading intelligence reports on that component based on machine to
machine process, RSS feeds, newspaper feeds or reports back from the providers of the
original data. In this way we can see a fully integrated operational environment for
complex economic (or any other statistics) information.</p>
        <p>They envisaged options for extending the environment to have parallel structures
for operational documentation, and setting up mash-up environments that can mine
for information from various database and web resources.</p>
        <p>While integration issues meant it was not feasible to move forward and realise the
wider vision at that time, strong support from the subject matter experts for
continuing this direction as soon as it is feasible continues remains a strong business driver
for ABS interest in pursuing practical application of semantic technologies.</p>
        <p>The vision from the business customer extended well beyond ASNA to a linked
network of CSMs for related fields of statistics.</p>
        <p>A network could (with less intense connections) then be extended to encompass
CSM information for all of the subject matter domains for which the ABS produces
statistics. For example, within economic and social statistics there are overlapping
concepts that are slightly different but should be by definition the same. One of the
main challenges is around the definition of income for households. In the social
framework, income for households is defined as the inflow of cash and benefits; in the
economic frameworks it is defined as an expenditure of business and government.
Once these are reconciled, metadata linkages will be much easier to manage.</p>
      </sec>
      <sec id="sec-11-2">
        <title>International Connections do we need this section?</title>
        <p>Since 2010 there has emerged a much stronger and more active focus among
National Statistical Institutes (NSIs) and international agencies on working together in
practice to achieve standards based modernisation based on collaboration, sharing and
reuse. Much of the leadership has been provided by the High Level Group for the
Modernisation of Statistical Production and Services (HLG) which comprises ten
heads of national and international statistical organisations, including the head of the
ABS.</p>
        <p>The strategy to implement the vision of the HLG includes positioning the “official
statistics industry” within the wider information industry and recognising a very
prominent connection with Open Data.</p>
        <p>This prominent connection is, in part, symptomatic of increasing interest over the
past three years among producers of official statistics in the opportunities that
ontologies and related semantic technologies offer.</p>
        <p>For example, NSIs have been active in initiatives such as “Open Government
Vocabulary” (US) and “Controlled Vocabulary Service” (Australia). They have also
been active in facilitating various “data.gov” initiatives around the world (eg UK,
New Zealand) including links to conceptual metadata structured on a semantic basis.</p>
        <p>The ABS is actively liaising with a number of NSIs who are currently undertaking
planning and development of “Conceptual Content Management Systems” that are
characterised by use of ontologies and related technologies.</p>
        <p>While the possibility remains under active consideration, a decision has not yet
been made by the ABS to seek to engage more closely with one of these projects as a
formal international collaboration.</p>
        <p>It appears certain in any case, however, that standards based, potentially sharable,
developments for managing statistical frameworks as ontologies will emerge within
the next few years. This includes the possibility of HLG focusing the attention of the
“official statistics industry” on this topic during 2014 or 2015.
11</p>
        <sec id="sec-11-2-1">
          <title>3. 2008 System of National Accounts,</title>
          <p>http://unstats.un.org/unsd/nationalaccount/sna2008.asp
4. Australian National Accounts: Concepts, Sources and Methods, ABS
Cat.no.5216.0, 2012,
http://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/5216.0Main+Features1
Edition%203?OpenDocument
5. Glossary from European System of national and regional accounts 1995,
http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Glossary:ESA9
5
6. IBM Notes/Microsoft Office
7. Gruber, T: A Translation Approach to Portable Ontology Specifications.</p>
          <p>Knowledge Acquisition, 5(2),199-220, (1993)
http://tomgruber.org/writing/ontolingua-kaj-1993.pdf
8. IBM Product Guide
http://www</p>
          <p>03.ibm.com/software/products/us/en/ibmnotes/
9. IBM Product Guide
http://www</p>
          <p>03.ibm.com/software/products/us/en/ibmdomino/
10. IBM Product Guide http://www-03.ibm.com/software/products/us/en/conn/
11. ABS IT environment
http://www.abs.gov.au/websitedbs/d3310114.nsf/0/b9043642361d7a66ca256b
59007bdae7/$FILE/Introduction%20to%20the%20ABS%20ICT%20Environ
ment.pdf
12. Australian National Accounts: Concepts, Sources and Methods, ABS
Cat.no.5216.0,
http://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/5216.0Main+Features1
Edition%203?OpenDocument</p>
        </sec>
      </sec>
    </sec>
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