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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Converging on Semantics to Ensure Local Government Data Reuse</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Laurens De Vocht</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mathias Van Compernolle</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anastasia Dimou</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pieter Colpaert</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ruben Verborgh</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Erik Mannens</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Peter Mechant</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rik Van de Walle</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>iMinds - Ghent University</institution>
          ,
          <addr-line>MICT Ghent</addr-line>
          ,
          <country country="BE">Belgium</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>iMinds - Ghent University</institution>
          ,
          <addr-line>Multimedia Lab</addr-line>
        </aff>
      </contrib-group>
      <abstract>
        <p>When building reliable data-driven applications for local governments to interact with public servants or citizens, data publishers and consumers have to be sure that the applied data structure and schema definition are accurate and lead to reusable data. To understand the characteristics of reusable local government data, we motivate how the process of developing a semantically enriched exchange standard contributes to resolving this issue. This standard is used, for example, to describe contact information for public services which supports a representative pilot for opening up a variety of local government data. After implementing the pilot, we experienced that supporting the process of converging on semantics has a catalyzing effect on the reusability of government data.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>If local governments would repeatedly develop an (ad-hoc) model for this
information, it would be really hard for them to maintain the services that offer this information,
as they require constant revising of the model of available data while they are not able to
cope with newer technologies and applications without heavily investing in new support
infrastructure. The opposite is also true, it is extremely easy to ignore this consideration
and just publish data in whatever format pops-up at the time. Therefore, we ensure that
after the standardization effort and as soon as the data has been described using one or
more vocabularies that: the data still remains reusable, even when information
technology evolves; and in one way or another, developers and users do not have to cope with
the same issues as with custom data models.</p>
      <p>
        Open standards are essential for systems and data to be interoperable [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. Without
open standards, open data can realize only a fraction of its value. Open data standards
and architectures facilitate the integration with existing systems and allow data to at
least be complete, primary and timely6. In the remainder of this paper we argue that
the nature of the Linked Data published needs a useful integration of data across
different administrations, where we aim at answering the question: How and why is this
integration effort for local and regional governments important for enterprises and
citizens? How do open standards help in achieving this integration?. We report on the
standardization effort and how we extended it to apply to a pilot for local governments.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        Historically, governments tend to rely on the free market to disseminate information,
e.g., the federal US Government, on the one hand, tries to reduce the role of the
government in presenting its information to citizens [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. In Europe, on the other hand,
several frameworks showed up as a key tool for interoperability in the deployment of
e-government services, both at national and at European level [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. To untangle those
legacies, many players in the private sector have embraced openness without
reservation.
      </p>
      <p>
        Methodologies for linking government data as such are not new: many guidelines
considering applications, methodology, coverage and quality exist [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. The Data-Gov
Wiki project [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] is particularly relevant for linking government data. In this project data
published at data.gov, a US portal for government data, was linked with LOD. It
covers a range of topics such as government spending, environmental records, statistics on
usage cost, use of public services. Around the same time, a similar effort for UK
government data (data.gov.uk) emphasized why and how Linked Data was introduced
and how a web of linked government data was created as part of the LOD cloud rather
than focusing on linking [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. These two government projects were preceeded by a
debate on choosing for a closed or open warehousing model [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. A tendency at the time
of writing was data storage causing a high demand for metadata integration, which is in
current terms translated to the need for a convergence on semantics of that data storage
and at the time implied already the need for standardization.
      </p>
      <p>
        Some initiatives succeed in this way of standardization, such as the EDGAR
filings with ‘eXtensible Business Reporting Language’ (XBRL)7: the ‘Securities and
Exchange Commission’ (SEC)8 mandate requires that corporations and mutual funds
under the purview of the Commission, file key performance reports in the Commission’s
EDGAR data repository9 in the XBRL format [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The Commission takes an approach
to XBRL emphasizing use of high-quality vocabularies. Arguably, this does not solve
6 http://opengovdata.org/
7 http://www.xbrl.org/
8 http://www.sec.gov/
9 http://www.sec.gov/edgar.shtml
the re-usability issue. There is no solution to this other than convincing governments to
take on responsibility for providing an important public good [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. For example, direct
feedback such as an interoperability score when a new dataset has been created within
a government can help the adoption of much used vocabularies [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Existing literature
lacks concrete case studies on solutions for this issue, but the “Financial Information
Observation System (FIOS)”10 uses Linked Data and multidimensional modeling of
XBRL based on the RDF Data Cube Vocabulary11 for accessing and representing
relevant financial data [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Similarly, an RDF mapping could be defined for existing SOAP
Web services [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. The evolution towards open data contributes to the timely aspect
because open data, either provided by the government itself or not, can enable the
measurement of achieved objectives [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. This helps citizens to understand and potentially
allows for better competition.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Semantic Representations Supported by Open Standards</title>
      <p>In an intergovernmental setting (with different structures as well as diverging public
service models) it is complex to optimize the delivery of government services so that
citizens and businesses only need to ask the government once for any of them. Even
within the same organization, public services are documented following different
flavors of national, regional or local public service models. Additionally, public service
descriptions delivered through e-Government portals are usually unstructured and not
machine-readable. This fragmented view of the public service concept and the absence
of machine-readable public service descriptions impacts the quality and the efficiency
of public service provision, increases administrative burdens and makes public service
provision more costly. This is a major obstacle for citizens and businesses.</p>
      <p>
        Smart Cities [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] are often confronted with: (1) a lack of open standards for (local)
government data and (2) the vertical and cumbersome structure of their data
architectures. The ISA core public services and the W3C Government Linked Data (GLD)12
Working Group have provided standards and other information to assist governments
around the world with publishing their data as effective and reusable Linked Data, using
Semantic Web technologies. However, thanks to the flexibility that the RDF data model
offers, local governments extend standards to serve their “custom needs” without
diverging from the originals. The specification of the Flemish extension13 of OSLO14,
was the result of our implementation of a public-private partnership. Our main task was
to formalize the exchange standard and its extension.
      </p>
      <p>In a typical scenario, local governments publish the open data, belonging to the
deliverable for a project, as part of an application or report. After delivery, shortage of
funding or change of focus to new projects leads to data which is not maintained. We
assure that the published data can remain correct and up to date. Therefore, we
modeled government data, described as Linked Data, with vocabularies in respect to their
usage and wide popularity within the Semantic Web community as well as to their
applicability for the proposed use case. The main modeling domains of interest as they
were indicated by the local governments during the development of OSLO are: people,
locations, organizations, products and services. To create new data sources, we
aggregated information from different regional and local e-government information systems
and combined them with existing services to create machine-readable public service
descriptions. These descriptions are reusable, following the Linked Open Government
10 http://fios.ontologycentral.com/
11 http://www.w3.org/TR/vocab-data-cube/
12 http://www.w3.org/2011/gld
13 https://github.com/v-ict-or/oslo_xml_</p>
      <p>
        schemas/tree/shared_catalogue_extension
14 https://github.com/v-ict-or/oslo_xml_
schemas/tree/master
Data paradigm [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] and enable functionalities such as automated service discovery and
composition.
      </p>
      <p>The Dublin Core vocabulary15 was used for the basic metadata properties, the Friend
of A Friend (FOAF)16 ontology to bind the information on titles and descriptions and
to enhance the content of the generated dataset. We used the OSLO vocabulary17 and
the W3C Organization vocabularies: Organization Ontology18, Registered Organization
Ontology19. For contact information we relied on the VCARD Ontology20. We have
extended the OSLO vocabulary with three new entities: Channel, Activity and Product. As
a result we are able to model the latter three and People, Organizations, Services and
Locations.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Shared Catalogue for Local Governments’ Public Services</title>
      <p>A number of administrations (local municipalities, cities and one regional
administration) participated, as depicted in Table 1, in the development of a prototype for the
“Shared Catalogue of Public Services”, an ecosystem for sharing contact information
from local governments: (i) towards citizens and (ii) between governments. The
participating administrations all experienced a considerable “overhead” and “redundancy” in
finding relevant contact data. The goal of this catalogue prototype is to disclose
products and services more effectively between governments and towards citizens. Figure 1
shows how they interact using a common interface providing access to the data
described semantically according to OSLO, enabling them to answer questions such as:
(i)“As a Citizen/Public Servant, how to obtain Service X in Municipality Y and who to
contact?”; (ii) “Who to contact for Service X in municipalities in a certain region?”.</p>
      <p>Administration Type
ISRBKGDKVHnieooeeanDgnvlsenroetAlttes-teklreNermBiklejlbikean*uke-r*nlHreagsaeteesinsrt CCCCRMMMMMiiiieuuuuuttttgyyyynnnnnioiiiiicccccniiiiiappppplaaaaallllliiiiitttttyyyyy</p>
      <p>Conceptually Mapped Formally Mapped Automatically Linked</p>
      <p>XXX XXX* X*
X
X
X
X
X</p>
      <p>X
X
X</p>
      <p>X*
X*
X</p>
      <p>The pilot was initiated by Corve21, the Flemish e-Government coordination cell
and the project consortium was coordinated by V-ICT-OR22, the Flemish ICT
organization. We analyzed the contact data from several Flemish municipalities and cities and
mapped according to the defined vocabularies. We dealt with multiple heterogeneous
data that needed to be mapped. Each government had its own data structure. After
mapping conceptually, i.e. matching concepts in the original datastructure with the OSLO
vocabulary, we defined a formal mapping to RDF in a configuration document. This
allowed us to align them for use in a common interface with one ‘move’. A couple of
governments, e.g., Beveren and Sint-Niklaas, could then be automatically linked without
having to do the conceptual and formal mapping again, as they used a similar back-end
data structure. It is noteworthy that for the biggest participating city, Gent, the mapping
15 http://dublincore.org/documents/dcmi-terms
16 http://xmlns.com/foaf/spec/
17 http://purl.org/oslo/
18 http://www.w3.org/TR/vocab-org/
is more time consuming. This is expected as the delivery of product and services is
more sophisticated and the data is more complex than for smaller governments.</p>
      <p>
        We relied on RML [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] to specify the mapping configuration. The data was based
on publicly available website data, so that there were no privacy-related issues. Each
municipality provided us with contact information of the members of the local
government, their function and role in offered products and services for citizens (e.g., demand
for a renovation permit or a new personal electronic passport). The mapped data was
published using The DataTank [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ], a system facilitating publishing datasets for
governments. It has recently added the required support for the persistence of links and
resolving Linked Data resources [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. By applying this approach, publishers only need
to worry about their source data and keep the links of published resources persistent,
regardless of the used format – which are in most cases CSV files or relational tables.
5
      </p>
    </sec>
    <sec id="sec-5">
      <title>Discussion and Conclusions</title>
      <p>In our opinion, supporting data reuse implies preparing facilities in advance with the
right vocabularies. This can be guaranteed on the ontology (semantic convergence) level
and the data level. Support groups, mailing lists and open maintenance helped ensuring
reuse of the ontology. In the case of data, and more specifically Linked Open Data, it
is important to have a solid feedback loop so that the original data publishers can be
notified at any point if there are any inconsistencies with the data they are responsible
for. To avoid inconsistencies, we maximized automation between reliable authentic data
sources and the published data.</p>
      <p>In this pilot, we have experienced that the Linked Data principles are as suitable
for data management on the Web as for local government information systems. We
developed a standard as a convergence between various stakeholders in local government
data. We showed its applicability using a prototype for a distributed shared catalogue
of public services and products from municipalities. We are going to continue
improving work in the field of Linked Open Government Data starting by assessing the user
perceived usefulness and usability of this approach. On the one hand, this application
is a typical use case for Linked Data technologies, given the complex and the dynamic
nature of the organizations and data involved. On the other hand, it also takes place in
a setting that is slow to evolve, partly for the same reasons. However, governments do
have the potential to force or imply a certain structure using their own resources.
Depending on the society model, short- and long term objectives, different technological
choices need to be made.</p>
      <p>We think that the Linked Open Data community should invest more in making its
technology essentials clear and in motivating governments to use it as main technology
for local government data reuse. It is an interesting research question to measure if and
how well agreeing on semantics proves to be useful in tackling issues on converging
semantics and reusable government data described in this paper.</p>
    </sec>
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