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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Annotation of Argument Components in Political Debates Data</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Shohreh Haddadan</string-name>
          <email>shohreh.haddadan@uni.lu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Elena Cabrio</string-name>
          <email>elena.cabrio@unice.fr</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Serena Villata</string-name>
          <email>villata@i3s.unice.fr</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Luxembourg, Universite ́ Coˆte d'Azur, Universite ́ Coˆte d'Azur</institution>
        </aff>
      </contrib-group>
      <fpage>12</fpage>
      <lpage>16</lpage>
      <abstract>
        <p>In this paper, we present the annotation guidelines we defined for annotating arguments in political debates. In our guidelines, we consider each argument as being composed of a claim and one or more premises. The annotation process has started with defining the guidelines for three annotators containing examples from the data, and continued as cyclic process of evaluation and revision on the annotation to resolve the ambiguities in the guidelines. In this paper, we briefly discuss the resulting annotated dataset and give some examples of the annotation scheme. The quality of the annotated dataset is assessed by computing inter-annotator agreement using Krippendorf's coefficient on a portion of the dataset.</p>
      </abstract>
      <kwd-group>
        <kwd>Argumentation Mining</kwd>
        <kwd>Argument Components</kwd>
        <kwd>Annotation</kwd>
        <kwd>Inter-annotator Agreement</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        The ability to make persuasive arguments is a crucial
characteristic for politicians in order to convince the public to
vote for them. Moreover, social scientists and historians
are interested in following the logical process of arguments
proposed by politicians. For instance, in the book “Lincoln,
Doglas and Slavery”
        <xref ref-type="bibr" rid="ref11">(Zarefsky, 1993)</xref>
        , the author analyses
the two presidential candidate’s arguments and their
reasoning strategies toward the specific issue of slavery. Thus,
social scientists and historians would highly benefit from
a tool able to assist them in detecting the arguments from
natural language documents.
      </p>
      <p>
        The rising field of Argument(ation) Mining
        <xref ref-type="bibr" rid="ref3 ref4">(Lippi and
Torroni, 2016b)</xref>
        aims at establishing the foundations of
formulating arguments and their reasoning process by
extracting argument components and the relations between them
from various types of textual resources. The
argumentation mining pipeline, more precisely, consists of several
stages which apply Natural Language Processing (NLP)
and Machine Learning (ML) methods. These stages include
the detection of argumentative vs non-argumentative
utterances, the classification of the argumentative utterances
with respect to the two classes of argument components
(i.e., premises and claims), and the prediction of the kind of
relation holding between these components. The output is
a structure where each argument is connected to the others,
providing in this way an overall view of the argumentation.
Supervised machine learning methods need annotated data
in the training phase. Hence, the need for annotated data
as an input to the argumentation mining pipeline is gaining
more significance.
      </p>
      <p>In this work, we first introduce the raw data used for
building this dataset in Section 2. Subsequently, in Section 3
we explain the scheme for argument component annotation
we defined by providing examples from the dataset. Then,
we explain the annotation process and the training process
of annotators in Section 4. Moreover, we discuss the
challenges which we confronted during the annotation process
relevant to the choice of dataset in Section 5. As a result
for this study we give an estimation of the quality of the
annotated dataset by computing the inter-annotator
agreement over a portion of the annotated dataset in Section 6.</p>
      <p>Section 7 concisely discusses previous work in argument
mining from political data.</p>
      <p>2.</p>
    </sec>
    <sec id="sec-2">
      <title>Dataset</title>
      <p>The dataset used for this study is taken from the
Commission on Presidential Debates (CPD) website which is an
independent nonprofit corporation sponsoring U.S.
presidential and vice-presidential debates. This dataset contains the
transcripts of debates that have been publicly broadcast1.
The first presidential debate ever held on television was the
debate between Kennedy and Nixon in 1960. Despite the
enormous audiences for the Kennedy-Nixon encounters, 16
years went by before the next series of debates. Thus, no
debate transcript exists in the dataset for 1964, 1968 and
1972. The dataset therefore includes 12 sets of debates
from 1960 to 2016 presidential election debates.
The dataset consists of 41 different transcripts in 12 years.
Table 1 shows a summary of the sum and average number
of turns of speech, sentences and tokens over the debate
transcripts of the whole corpus.</p>
      <p>SUM
AVERAGE</p>
      <sec id="sec-2-1">
        <title>Turns of Speech 6,907 160.6</title>
      </sec>
      <sec id="sec-2-2">
        <title>Sentences 36,988 860.186</title>
      </sec>
      <sec id="sec-2-3">
        <title>Tokens</title>
        <p>678,291
15,774.21
3.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Annotation Scheme</title>
      <p>
        In this study, we aim at proposing an annotation scheme
for the annotation of argument components in political
debates. As mentioned in Section 1, arguments consist of two
major components, in this section we will provide the
definitions and some examples from the dataset for these
argument components which represent the key element of the
annotation scheme for our dataset. The argument
components annotated for this dataset are claims and premises.
According to Toulmin’s model of reasoning, the basic triad
of an argument consists of three main components: claim,
1http://www.debates.org/
data and warrant
        <xref ref-type="bibr" rid="ref9">(Toulmin, 2003)</xref>
        . Claims are the basic
component of arguments. Claims are made so that the
audience of the argument accept them, they can also be
considered as conclusion of the argument. Data is the component
of the argument which is provided in order to support the
truth of the made claim. Warrants are components which
connect the claim to data by certifying whether its
reasonable. Warrants are typically implicit and are not stated on
the premise that the audience can infer them. Figure 1
illustrates Toulmin’s model’s basic triad by giving an
example from John Kennedy’s speech in debate against Richard
Nixon in 1960: 2
“[In my judgment, the hard money, tight money policy,
fiscal policy of this Administration has contributed to
the slow-down in our economy], [which helped bring the
recession of fifty-four]; [which made the recession of
fifty-eight rather intense], and [which has slowed,
somewhat, our economic activity in 1960].”
Our annotation scheme includes the annotation of argument
components which are claims and premises (referred to as
data in Toulmin’s model).
In political debates, a claim may suggest a policy advocated
by a party or a candidate to be undertaken which needs to
be justified in order to be accepted by the audience. Claims
may also be made to take a stance towards a certain policy.
They might state an opinion or belief or judgment towards
a specific issue.
      </p>
      <p>In order to help annotators in finding claims we have
suggested some indicator phrases which were commonly used
by the candidates while making claims, such as: I believe,
in my opinion, I am in favor of, I think ,etc.</p>
      <p>Political debates are rifled with all types of various claims,
in order to make the definitions clear some examples are
provided from the dataset in the following.</p>
      <p>2Claims are written in bold and premises are written in italics.
Component boundaries can be distinguished by [square brackets].</p>
      <sec id="sec-3-1">
        <title>1. “[I feel that another effort should be made by a new</title>
      </sec>
      <sec id="sec-3-2">
        <title>Administration in January of 1961, to renew nego</title>
        <p>tiations with the Soviet Union]”.3</p>
      </sec>
      <sec id="sec-3-3">
        <title>2. “[George Bush, who I think is one of the finest Vice</title>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Presidents this country has ever had], ”.4</title>
      <sec id="sec-4-1">
        <title>3. “[I’ve opposed the death penalty during all of my</title>
        <p>life]. ”5</p>
      </sec>
      <sec id="sec-4-2">
        <title>4. “[I believe that we’ve got to get the power in the</title>
        <p>hands of the teachers, not the teachers’ union]”6
Examples 1 and 4 are claims which are asserting a certain
policy, in example 2 an opinion is made and 3 depicts a
claim in which the debater declares his stance against a
policy.</p>
      </sec>
      <sec id="sec-4-3">
        <title>3.2. Premise</title>
        <p>In this annotation scheme we refer to the concept of data
defined in Toulmin’s model as premise. Premises are
utterances asserted by debaters to justify a claim.</p>
        <p>Similar to claims, we have also given some examples of
indicators in the guidelines which help the annotators in
finding premises in the debates. These indicators are: because,
for example, for instance, so and etc. We have also
mentioned in the guidelines that claims and premises sometimes
come without any indicators, thus no part of these debates
can be skipped for annotation.</p>
        <p>Premises in political debates are also provided in several
forms consisting facts, statistics, quotations, reports or
examples, findings, physical evidence, or other reasoning
methods. Several examples of the premises existent in the
dataset are provided in the following.</p>
        <p>5. [Every estimate by this administration about the
size of the deficit has been off by billions and
billions of dollars]. As a matter of fact, [over 4 years,
they’ve missed the mark by nearly $600 billion].
[We were told we would have a balanced budget in
1983]. [It was $200 billion deficit instead]. And now
we have a major question facing the American
people as to whether we’ll deal with this deficit and get it
down for the sake of a healthy recovery. [Virtually
every economic analysis that I’ve heard of, including the
distinguished Congressional Budget Office, which is
respected by, I think, almost everyone, says that even
with historically high levels of economic growth, we
will suffer a $263 billion deficit]7.
6. [I have submitted an economic plan that I have worked
out in concert with a number of fine economists in this
country, all of whom approve it], and [believe that
over a five year projection, this plan can permit the
extra spending for needed refurbishing of our
defensive posture], that [it can provide for a balanced
budget by 1983 if not earlier]8
3Kennedy- 13 October 1960 in debate against Nixon
4Reagan- 21 October 1984 in debate against Mondale
5Dukakis- 13 October 1988 in debate against Bush
6Bush- 15 October 1992 in debate against Clinton and Perot
7Mondale, October 7, 1984 in debate against Reagan
8Reagan, October 28, 1980 in debate against Carter
7. [The terrorism czar, who has worked for every
president since Ronald Reagan, said, ”Invading Iraq in
response to 9/11 would be like Franklin Roosevelt
invading Mexico in response to Pearl Harbor”].9
In examples 5 and 6 the debater tries to convince the
audience of the credibility of his claim by giving as
premise the confirmation of his claim by experts as
references and in 7 the debater uses a quote as source
to justify his claim.</p>
        <p>Premises can be stated as examples to justify the truth
of a claim. In order to support a claim or come to
a conclusion a debater may provide examples which
will in our definition can be considered as premises.</p>
        <p>Examples of such premises are found in 8.
8. [Race remains a significant challenge in our
country]. [Unfortunately, race still determines too
much], [often determines where people live],
[determines what kind of education in their public schools
they can get], and, yes, [it determines how they’re
treated in the criminal justice system]. [We’ve just
seen those two tragic examples in both Tulsa and
Charlotte].10
In the examples above premises include facts such as the
first three premises in example 8, or reports as instances
which confirm the claim such as the last sentence in
example 8. The warrant of the use of this premise is that it’s
plausible to generalize an occurrence of an event to deduct
a rule.</p>
        <p>4.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Annotation Process</title>
      <p>
        The annotation process is carried out by three annotators
who have started annotating the argument components on
the dataset using brat11 annotation tool
        <xref ref-type="bibr" rid="ref8">(Stenetorp et al.,
2012)</xref>
        set up on an standalone server.
      </p>
      <p>Training of the annotators is performed as a cyclic chain
of test and trial. Firstly, a guideline was prepared to
describe the annotation scheme with definitions and examples
from the dataset, with common structures and controversial
examples to train the annotators for the process. Figure 2
depicts this cyclic process.</p>
      <p>Test periods were dedicated to the evaluation of each
annotator based on their assigned annotation by two experts
in the field of argumentation. After receiving the
evaluation, their common mistakes were discussed and they were
asked to revise their annotations. After each evaluation
period the guidelines were revised by adding more examples
for clarification according to the common mistakes made by
annotators such as recognition of component boundaries,
clarification of the differences between components. Trial
periods are designed to observe the accordance of the
annotation performed by annotators to the annotation by an
expert and computing the inter-annotator agreement for the
annotation.</p>
      <sec id="sec-5-1">
        <title>9Kerry, September 30, 2004 in debate against Bush 10Clinton, 26 September 2016 in debate against Trump 11http://brat.nlplab.org/</title>
        <p>We confronted a number of challenges in the annotation
process of the dataset.</p>
        <p>
          The first challenge we encountered was the unstructured
nature of the spoken language compared to written
language such as persuasive essays which is used in
          <xref ref-type="bibr" rid="ref7">(Stab and
Gurevych, 2014)</xref>
          . Lack of writing structure leads to lack of
argument structure in this dataset. Thus, many claims exist
in this dataset for which the candidates do not provide any
justification. This is usually not the case in written
argumentative essays.
        </p>
        <p>
          Secondly, the task of annotating the arguments of a text
is highly context-dependent, therefore annotators are
supposed to decide tagging mainly based on the context. The
problem in this dataset is that in a dialogue there are no
specific boundaries to limit the context. In a persuasive essay,
one might suggest that the annotators read a whole
paragraph or even the whole essay to decide whether a sentence
is a claim in the context of the essay as done in
          <xref ref-type="bibr" rid="ref7">(Stab and
Gurevych, 2014)</xref>
          . This is however not possible in the
debates dataset. In the guidelines we roughly suggested that
the annotators read each speech turn first and then start
annotating it.
        </p>
        <p>In the guidelines we have provided some indicator phrases
to facilitate the process of finding claims and premises in
the text. Although these indicators can be helpful in most
cases, there are cases in which they could mislead the
annotators. Occurrence of these indicators in a sentence is
not a guarantee that argument components are used in the
sentence, this is shown in example 9.</p>
        <p>9. IFILL: In that case, we’ll move on to domestic matters.</p>
        <p>And this question, I believe, goes to Senator – to Vice
President Cheney. The Census Bureau</p>
        <p>
          CHENEY: I think it goes to Senator Edwards.12
Another one of the main challenging characteristics of
political debates is that there is no specific topic for each of the
arguments that occur in the debate separately. Thus, unlike
the work of
          <xref ref-type="bibr" rid="ref7">(Stab and Gurevych, 2014)</xref>
          , we cannot annotate
any part of the document as a major claim for the current
arguments of the debate and specify which claims are
asserted under the topic of one major claim. We therefore
have confined our annotation scheme for the annotation of
components to claims and premises.
12October 5, 2004
6.
        </p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Annotation results</title>
      <p>In this study, the reliability of annotated dataset is measured
by an inter-annotator agreement quantifier. This section
provides some statistics and according to the partial
annotation of the dataset until now13.</p>
      <p>We provide the distribution of annotated components
roughly both at sentence level and token level.</p>
      <p>Table 2 illustrates the percentages of argument components
annotated in the dataset. The sum percentage exceeds a
hundred percent which indicates that there are less than
0:1% sentences which contain more than one component
annotation. Since this difference is trivial we are going to
present the IAA in measure of number of sentences
containing argument components as an approximation.
Due to the large size of the corpus, instead of having each
annotator annotate every transcript available in the corpus,
we have decided that each transcript in the dataset should
be annotated by two annotators.</p>
      <p>Thus, the inter-annotator agreement is computed according
to the agreement between each pair of the annotators and
then reported as the average of these different reliability
values.</p>
      <p>
        In Table 3, we compute the agreement between boundaries
of annotated vs non-annotated parts. The first column in
table 3 shows the observed agreement value which is a
quantity showing agreement over the annotation without
chance correction. The second column uses a chance
corrected inter-annotator reliability named Kripendorff’s
introduced in
        <xref ref-type="bibr" rid="ref2">(Krippendorff, 2004)</xref>
        . The agreement of 0.6209
is the average agreement between different annotators on
same transcripts.
      </p>
      <sec id="sec-6-1">
        <title>Annotator Pairs A and B A and B A and C</title>
        <p>Average</p>
        <p>Average
served
ment
0.8649
0.8624
0.7737
0.8336</p>
        <p>ObAgree</p>
        <p>Agreement
based on
Kripendorff’s
0.6791
0.6463
0.5374
0.6209</p>
        <p>The Confusion Probability Matrix (CPM) in Figure 3
illustrates the normalized disagreement between the annotators
on sentence-level between different components.</p>
        <p>13The results in this section only covers 30 percent of the whole
corpus which was annotated during the first cycle in the process.
It can be inferred from the results in Figure 3 that the
disagreement between premise and claim is very high. This
disagreement often occurs due to the fact that some claims
provided by debaters can be inferred as premises. For
instance, in example 10, the sentence [Communism is the
enemy of all religions] is provided to support the claim
why [we who do believe in God must join together].
Although it is a claim which should be proven, there is no
justification why that’s a true statement and the debater uses
it to support his previous claim therefore might be
misannotated as a premise.
10. Nixon-Kennedy- October 13 1960:
[Communism is the enemy of all religions]; and [we
who do believe in God must join together]. [We
must not be divided on this issue]
7.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>Related work</title>
      <p>
        The political domain allows for intuitive applications of the
argument mining framework with the final aim of
detecting fallacies, persuasiveness degree and coherence in the
candidate’s argumentation.
        <xref ref-type="bibr" rid="ref3 ref4">(Lippi and Torroni, 2016a)</xref>
        address the problem of argument extraction, and more
precisely claim detection, over a corpus based on the 2015
UK political election debates. They aim to study the
impact of the vocal features of speech on the claim detection
task. The Internet Argument Corpus14 (IAC)
        <xref ref-type="bibr" rid="ref10">(Walker et
al., 2012)</xref>
        collects the posts from 4forums.com, a
website for political debate. The debates have been annotated
for argumentative markers like degrees of agreement with
a previous post, cordiality, audience direction,
combativeness, assertiveness, emotionality of argumentation, and
sarcasm.
        <xref ref-type="bibr" rid="ref1">(Duthie et al., 2016)</xref>
        apply AM methods to detect
the presence and polarity of ethotic arguments from UK
parliamentary debates.15 The authors also investigate how
14http://nlds.soe.ucsc.edu/software
15http://arg.tech/Ethan3Train,
//arg.tech/Ethan3Test
http:
their results can be visualized to support user
understanding.16
        <xref ref-type="bibr" rid="ref6">(Naderi and Hirst, 2015)</xref>
        show how features based
on embedding representations can improve discovering
various frames in argumentative political speeches. They
propose a corpus of speeches from the Canadian Parliament,
and they examine the statements with respect to the
position of the speaker towards the discussed topic (pro, con, or
no stance). In
        <xref ref-type="bibr" rid="ref5">(Menini et al., 2018)</xref>
        , we address the relation
prediction task on political speeches in monological form,
where there is no direct interaction between the opponents.
We created a corpus, based on the transcription of speeches
and official declarations issued by Nixon and Kennedy
during 1960 Presidential campaign, of argument pairs
annotated with the support and attack relations.17 None of these
approaches considers the annotation of argument
components (i.e., premises and claims) on a corpus of political
debates, which is the object of our contribution.
8.
      </p>
    </sec>
    <sec id="sec-8">
      <title>Conclusion</title>
      <p>In this paper, we have discussed the issue of identifying
premises and claims in political debates. More precisely,
we have presented the annotation guidelines we defined to
train the annotators. The guidelines define what we mean
by premises and claims in the context of political debates,
and provide several examples to show instances of these
two argument components. Since we are in the annotation
phase of our dataset, we discussed the challenges we faced
in training the annotators for this non trivial task, and we
provide some statistics about the current status of our
resources.</p>
      <p>Future work includes the finalization of the annotation
process of the dataset of political debates, and the definition
of suitable NLP methods for the automatic identification
of these argument components and the relations between
them.
16https://goo.gl/P9fyzi
17https://dh.fbk.eu/resources/
political-argumentation</p>
    </sec>
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