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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Datastores for Argumentation Data</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Edinburgh Napier University</institution>
          ,
          <addr-line>Edinburgh</addr-line>
          ,
          <country country="UK">United Kingdom</country>
        </aff>
      </contrib-group>
      <fpage>31</fpage>
      <lpage>40</lpage>
      <abstract>
        <p>This paper introduces SADFace, a simple argument description format, and ArgDB, a datastore for managing datasets of SADface documents, in the wider context of a nascent e ort to develop an Open Argumentation platform. CMNA'20 - F. Grasso, N. Green, J. Schneider, S. Wells (Eds) - 8th September 2020 Copyright c 2020 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).</p>
      </abstract>
      <kwd-group>
        <kwd>Argumentation Datasets Argumentation Tools Argumentation Software Open Source Software Open Development Platforms</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        In recent years, there has been a gentle turn towards a more data-driven
approach to argumentation research and whilst research in argumentation theory
has always been rooted in real world practise, studying examples of actual
argumentative behaviour amongst people, the increasing use of digital machinery to
process and engage in argument is leading to the creation of, and exploitation of,
ever larger argumentative datasets. A problem arises when a software developer
begins to develop tools that are aimed at exploiting, facilitating, capturing, or
analysing online argumentation; they often have to start from scratch, building
on the published research output. This is the traditional mode of exploitation
of research ndings, but it represents an opportunity whereby, if a little more
e ort is made to enable the development of public argumentation systems, then
a variety of rich sources of argumentative data might be created which can in
turn be utilised in more data-intensive argumentation research such as Argument
Mining[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. This paper reports on an ongoing and open-ended e ort to provide a
set of free, open-source, and open-development, tools, libraries, and formats that
can underpin future generations of digital argumentation software. The core of
the system reported here is a format for describing argument data and a
datastore for holding that data. These are introduced in the context of argument
analysis, using the MonkeyPuzzle tool, but actually form core technologies for
the Open Argumentation PLatform (OAPL)1 [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ].
      </p>
      <p>
        Whilst much argumentation software has been developed over the years,
supporting a wide range of argumentation-related tasks (including Araucaria [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ],
Arvina [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], Carneades [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], Rationale [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] to name but a few), considerably less
      </p>
      <sec id="sec-1-1">
        <title>1 http://www.openargumentation.org</title>
        <p>
          e ort has gone into producing a sustainable eco-system of tools that can work
together, can support a distinct and identi able set of argumentation-oriented
work ows, and which can bring applied argumentation theory out of the lab and
into the wider software and computational communities. Some e orts have
occurred to promote some cohesion between software, most notably the Argument
Interchange Format (AIF)[
          <xref ref-type="bibr" rid="ref2">2</xref>
          ], however this hasn't seen the kind of community
uptake and tooling provision that is necessary for it to ful ll a role as the
interface to argument data for the wider software community. Rather, the AIF has
arguably developed into a useful and powerful theoretical and ontological model
but lacks the ease of use and immediacy that characterises many tools, especially
in the Web arena, that see signi cant and wide-spread uptake. An example of
this occurring in data representation would be comparing the power and
extensibility, and consequent challenge to ease of use, of RDF and XML languages
and technologies, versus JSON which has arguably become the standard for data
interchange on the Web.
        </p>
        <p>
          It is important to note that whilst proposals are made herein for particular
tools to achieve speci c aims, e.g. SADFace to describe structured argument
and ArgDB to store those structures, this is not meant to occur in an exclusive
fashion. An ideal outcome is that there is a healthy ecosystem of inter-operable
argumentation software, featuring a multitude of ways to achieve the various
goals that a developer or researcher might set and that it is easy for any one,
or even for all, of the tools in a given toolchain to be exchanged for
alternatives. There is some healthy development in this area, particularly in the tooling
around ArgDown2 [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ] and the continued development of the Carneades
argumentation system. This work di ers in somewhat to each of these, aiming to
provide a more comprehensive set of tools than ArgDown, and providing a less
integrated and more exible toolset than Carneades, but coexisting with each.
The remainder of this paper is structured as follows: In sections 2 and 3 the
underpinning technologies, SADFace and ArgDB, respectively for this architecture,
are introduced. In section 4 a brief overview of an argument analysis pipeline is
explored. Finally, in section 5, some directions for future work, and the wider
context of an open argumentation platform, are discussed.
2
        </p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>SADFace</title>
      <p>The Simple Argument Description Format (SADFace) is a JSON3 language for
describing and sharing structured argument data. JSON is a lightweight data
interchange format that is generally considered to be more human-readable than
competitor formats like XML or RDF. This means that SADFace can easily be
manipulated by a person using a plain-text editor. However, to do so misses out
on the additional tooling that supports the SADFace language. In the remainder
of this section, we will give an overview of the SADFace language in section 2.1
before describing the supporting tools and library implementations in section 2.2,</p>
      <sec id="sec-2-1">
        <title>2 https://argdown.org/</title>
      </sec>
      <sec id="sec-2-2">
        <title>3 https://www.json.org/json-en.html</title>
        <p>before brie y discussing the role of SADFace in relation to the AIF in section 2.3.
Detailed information regarding SADFace is available from the Git repository4.
2.1</p>
        <sec id="sec-2-2-1">
          <title>SADFace Language</title>
          <p>SADFace is a simple JSON based Argument description format, software
library, and supporting tools to enable developers and researchers to describe
arguments, capturing content and associated metadata, and to then easily reuse
their data. The goal is to make it as easy as possible to incorporate argument
data into modern software. There are a number of argument description and
markup languages, for example, the Argument Markup Language (AML) and
the Argument Interchange Format (AIF). Both have their advantages and
disadvantages, AML is a simple tree-based format, but is challenging to parse,
and requires an XML toolchain, something that is falling out of favour amongst
main-stream web toolchains. AIF on the other hand provides an excellent,
extensible high-level ontology for representing arguments, dialogues, schemes, and
many peripherally related concepts. However with AIF that exibility has the
price of opaque terminology and complexity, both in terms of underlying model
and in terms of the required RDF and XML toolchains. Where both of these
formats fail is in the documentation, support, and maturity of libraries for users
who want to work with them. It is a big, perhaps prohibitive, requirement for
a developer to start their adoption of a format by rst having to write a parser
or library for it. A more preferable set of circumstances is for the developer to
be able to merely import a pre-made and tested library for their chosen
language. SADFace seeks to address some perceivable drawbacks of other formats.
It has a simple underlying but extensible model that is compatible with core
AIF concepts, clear extension points for domain speci c analysis and
representation tasks, tooling to support import from other formats, e.g. AML and AIF,
an open source canonical implementation maintained in a public Git repository,
documentation, supporting tools for creation, editing, and manipulation, liberal
(GPL3) licensing, and an open development model in which anyone is free to
contribute enhancements or to fork their own development branch. A developer
should be able to adopt SADFace and start describing arguments or using those
descriptions, really easily. Parsing a SADFace document into a Javascript
application should not require any special tools, it is just JSON. The structure of
the format has been designed to align with a straightforward model of argument
structure, de ned in such a way as to align with most of the intuitions that an
everyday understanding of argument will include, whilst still supporting more
advanced features.</p>
          <p>In SADFace, arguments are constructed from statements (or strings) that
capture a \claim". These statements are called \Argument Atoms", or just
\atoms". A simple argument is a collection of such atoms that are linked
together. For a simple argument one of the atoms is a conclusion, and the other
atoms in that argument are premises. The exact way that premises support a</p>
        </sec>
      </sec>
      <sec id="sec-2-3">
        <title>4 https://github.com/Open-Argumentation/SADFace</title>
        <p>
          conclusion is captured by the idea of argumentation schemes[
          <xref ref-type="bibr" rid="ref12">12</xref>
          ]. An
argumentation scheme describes a stereotypical pattern of argumentative reasoning, so
di erent arguments can be categorised into di erent types. In SADFace atom
nodes are not directly linked to each other but are linked via an
\Argumentation Scheme Node", or \scheme" node. Whilst we often characterise arguments
in terms of a directed graph, with the premises leading to a conclusion, which in
turn might act as a premise in a further argument, with some other conclusion,
SADFace edges are bi-directional, enabling a programmer to move through the
argument graph easily in either direction. A SADFace document contains a set
of nodes, a set of edges, and metadata. Edges are simple, they have an ID so
that the instance of the edge can be uniquely identi ed from all other edges,
and they also have a source and a target. The source and target in an edge are
both IDs of nodes, i.e. the ID of the node that this edge goes from, the source
ID, and the ID of the node that this edge goes to, the target ID. Nodes are
slightly more complicated, currently there are two types of node, atom nodes
and scheme nodes. Atoms and schemes are connected using the aforementioned
edges. Metadata captures data associated with the document, who analysed,
when this happened, a title, additional notes, etc. An optional element of
SADFace is the resources section which records all of the sources that the argument
has been analysed from. This enables a single SADFace document to reference
multiple underlying originating sources of content and opens the way for an
analysis to capture an entire target domain, rather than a single source text.
An example SADFace document is shown in Fig. 1. An important aspect of the
SADFace design is the de ned extension points so that end-users add their own
metadata, to suit their own problem domain, in namespaced sections (where the
\core" namespace is reserved for SADFace usage) to which they can add their
own metadata. Such sections are referred to as `regulated' sections. Additionally,
the validation methods provided in the SADFace libraries work on the following
two principles: rstly, the required sections must be present but additional
section will be ignored, and secondly, all required sections and all regulated sections
must be correctly formed.
2.2
        </p>
        <sec id="sec-2-3-1">
          <title>SADFace Implementation &amp; Tooling</title>
          <p>There are currently two library implementations supporting SADFace, a Python
3 and a JavaScript implementation which are developed primarily to provide
native library APIs within their respective languages. The JavaScript
implementation is intended to enable web apps, running in the browser, or hosted in Node.JS,
to read, write, and verify SADFace documents. The Python implementation is
more mature than the JavaScript implementation and provides supporting tools
for interacting with SADFace documents beyond merely creating and updating
them. For example, the Python implementation additionally support upgrading
and downgrading versions of SADFace as the format develops, enhanced
validation, pretty-printing, as well as import and export to other formats like AML,
AIF, and Dot/GraphViz. In addition to use as a library, the Python
implementation has other modes of usage including a scriptable command line interface
],
"metadata": {
"core": {
"analyst_email": "siwells@gmail.com",
"analyst_name": "Simon Wells",
"created": "2019-04-22T23:52:30",
"description": "An example SADFace document showing an argument
analysis of the Hangback cycle safety campaign from the</p>
          <p>STCD corpora.",
"edited": "2019-04-22T23:52:30",
"id": "42e56df7-4074-40d8-8ea1-4fca5321dd31",
"notes": "This is incomplete because the analysis in Pangbourne
\&amp; Wells (2018) has much more argumenative content.",
"title": "Hangback Example",
"version": "0.2"
}
},
"nodes": [
{
"id": "ae3f0c7f-9f69-4cab-9db3-3b9c46f56e09",
"metadata": {},
"sources": [],
"text": "The 'Hang Back' campaign video should not have been
published, and should be withdrawn.",
"type": "atom"
},
...
],
"resources": []}
that exposes most core API functions from the SADFace library. This is
useful for incorporating SADFace within a pipeline or shell script, for example, to
take an AML document, convert it to SADFace, then to export the resulting
le to a DOT representation and pipe it to GraphViz, ultimately yielding an
image le for visualisation. Furthermore, there is a Read-Evaluate-Print-Loop
(REPL) that enables users to interactively construct and manipulate SADFace
documents from within a text oriented shell interface.
2.3</p>
        </sec>
        <sec id="sec-2-3-2">
          <title>SADFace &amp; The Argument Interchange Format</title>
          <p>
            The question, `why not just use the AIF?' is appropriate and will now be
addressed. AIF is an excellent, general-purpose, upper ontology for representing
and describing argumentation concepts in an extensible fashion. The AIF has
enabled argumentation researchers to distinguish a variety of argument-related
concepts and to describe those concepts in technical detail su cient for
computational exploitation. For example, describing concepts related to Argumentation
Schemes [
            <xref ref-type="bibr" rid="ref7">7</xref>
            ], Dialogue [
            <xref ref-type="bibr" rid="ref10">10</xref>
            ], and social interaction [
            <xref ref-type="bibr" rid="ref6">6</xref>
            ]. However, whilst
theoretical extensions to the AIF have continued to develop, and the AIF provides a
useful lingua franca for e ective communication and understanding between
researchers, this has not been matched by uptake amongst software developers in
subsequent years, despite some e ort to present a cohesive online presence5. For
example, whilst the web has developed into a de facto environment for discussion,
the infrastructure for exploiting and reusing the content of those discussions, has
not kept pace. The AIF does not have a canonical implementation, for
example, a software library, that enables developers to exploit the rich theoretical
knowledge captured therein. SADFace has been developed to be consistent with
AIF design principles, such as the graph based core structure and restriction
on edges carrying data, but a key design decision was to be consistent,
understandable, and build around a small, solid extensible core that is rei ed in a
canonical software implementation, and which is in turn underpinned by testing
and documentation.
3
          </p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>ArgDB</title>
      <p>The Argument Database (ArgDB) is a datastore and supporting software for
collecting, manipulating, interacting with, and reusing, analysed and structured
argumentation data described using the SADFace format. More speci cally, ArgDB
is a set of Python tools for creating, managing, and searching multiple datasets
of SADFace documents. Python was selected because it is a mature language
that is widely used and is particularly prevalent in server-side Web development,
in data science, and in modern, data-driven AI research. As a result the use of
Python should reduce the barrier to entry for adoption of ArgDB in those areas.
The idea is that those using argumentative data may need to keep some datasets</p>
      <sec id="sec-3-1">
        <title>5 http://www.argumentinterchange.org/</title>
        <p>separate from others, for example, if working on di erent funded projects, or
because of the nature of the data requires heightened security or privacy steps to be
taken such as when working with private, personal, medical, or legal argument
data. A core design decision is support for multiple, separate databases that can
all be managed from a single ArgDB instance. This enables a user to store
cohesive datasets separate from each other, if collating everything together is
undesirable, or else to mix argument documents together as required by their own goals.
Technically, ArgDB provides a set of argumentation task oriented interfaces to
a pre-existing, underlying database technology. Presently this technology is the
Apache CouchDB6 a JSON document store that provides map-reduce based
indexing and search capabilities together with an HTTP/JSON API and
replication and synchronisation capabilities. Whilst there are other datastores that
provide an overlapping set of features which might have su ced for present
purposes, out-of-the-box CouchDB provides all of the functionality necessary for the
current ArgDB, as well as a pathway towards future features. For example, one
very desirable feature would be to enable researchers and groups to easily share
and replicate argumentative datasets, a feature that can be built into ArgDB
by exploiting CouchDB's existing replication and synchronisation features.
Detailed information regarding SADFace installation and usage is available from
the project's Git repository7.
3.1</p>
        <sec id="sec-3-1-1">
          <title>ArgDB Interfaces</title>
          <p>The ArgDB tools are implemented in Python 3, support a variety of ways to
interact with the ArgDB, and are designed to support the construction of a variety
of work ows. Current interfaces include an application programming interface, a
command line interface (CLI), a read-evaluate-print loop (REPL), and a
graphical user interface (GUI). A single Python implementation hosts the core of the
ArgDB functionality, which provides an API for interacting with the underlying
CouchDB software. This API is intended for integration of ArgDB functionality
within end-users own software applications. This API is also used by the CLI,
REPL, and GUI interfaces to access ArgDB functionality. The CLI provides a
scribtable interface, enabling single command line invocations, or more
extensive scripts to create and delete databases, to verify, add, update, and delete,
SADFace documents within those databases, and to search the contents of the
stored documents, either withing a single database or across multiple databases.
The GUI utilises a web view facilitated by the Python PyWebView8 project.
This enables an interface based upon the core web technologies, HTML, CSS,
and JavaScript to be provided, in a cross-platform fashion, to multiple operating
systems. The web view provides an interface to the native installed web browser
and enables the ArgDB GUI to appear as a local graphical application. The
current GUI interface is shown in Fig. 2 and is currently, primarily, focussed upon
exposing the search facility to users.</p>
        </sec>
      </sec>
      <sec id="sec-3-2">
        <title>6 https://couchdb.apache.org/</title>
      </sec>
      <sec id="sec-3-3">
        <title>7 https://github.com/Open-Argumentation/ArgDB</title>
      </sec>
      <sec id="sec-3-4">
        <title>8 https://pywebview. owrl.com/</title>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Case Study: Using MonkeyPuzzle to construct a persistent collection of analysed argumentative data</title>
      <p>
        In order to demonstrate ArgDB in earnest requires a source of
argumentation data. The easiest method is to generate newly analysed arguments,
represent these analyses using SADFace, and to store the result in ArgDB. This
is merely one of the core work ows that is currently supported but is not the
end-goal9. MonkeyPuzzle [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] is a browser-based, open-source, argument
analysis web-interface. It currently runs either standalone or hosted on a web server.
Basic interaction is in the style familiar from Araucaria, text is selected from a
resource pane and used to create a new node in the diagram. Nodes are then
linked together via scheme nodes to construct arguments in which the arrow
directed out from a scheme indicates a conclusion, and arrows directed towards
a scheme indicate premises. Users can load an argumentative text into
MonkeyPuzzle and analyse it in the fashion of Rationale or Araucaria. The analysed
argument can be exported to a SADFace document using the JavaScript
SADFace library and imported into an ArgDB database. This structured argument
document can then be retrieved, updated, or deleted from the resulting dataset
but is persisted ready for retrieval in other contexts.
      </p>
      <sec id="sec-4-1">
        <title>9 See the future work described in section 5 for an indication of the kinds of work ows</title>
        <p>that are in active development</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Conclusions &amp; Future Work</title>
      <p>
        To conclude, we have presented two technologies, SADFace and ArgDB, that
work together to provide a data storage platform for structured argumentation
data. One strand of future work will involve continuing to enhance the core
SADFace technology whilst exposing any new functionality via ArgDB. A
second strand of work places these two technologies at the core of a wider `Open
Argumentation PLatform' (OAPL). This is a nascent e ort to stimulate the
development of a set of open source argumentation technologies that (1) work
together to provide a coherent set of argument oriented toolchains and
workows (to support (a) automated reasoning using the ALIAS tool and library
[
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], (b) argument mining [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], and (c) dialogical interaction based upon the
Dialogue Game Description Language (DGDL) [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]), (2) can form the basis of
new research directions, (3) have a long-term, open development plan, and (4)
which can be integrated more easily into the wider world of computing, perhaps
to help ful ll some of the promise of an Argument Web[
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
    </sec>
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