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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Why It's Fake: Developing an Explainable User Interface for a Fake News Detection System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Erasmo Purificato</string-name>
          <email>erasmo.purificato@ovgu.de</email>
          <xref ref-type="aff" rid="aff2">2</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Saijal Shahania</string-name>
          <email>saijal.shahania@ovgu.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ernesto William De Luca</string-name>
          <email>ernesto.deluca@ovgu.de</email>
          <xref ref-type="aff" rid="aff2">2</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="editor">
          <string-name>Explainability, User Interface, Fake News Detection</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Georg Eckert Institute</institution>
          ,
          <addr-line>Brunswick</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>German Centre for Higher Education Research and Science Studies</institution>
          ,
          <addr-line>Hanover</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Leibniz Institute for Educational Media</institution>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Otto von Guericke University Magdeburg</institution>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2016</year>
      </pub-date>
      <abstract>
        <p>In this paper, we present the design and development of an explainable user interface for a fake news detection system. The problem of distinguishing real from fake articles gained a lot of popularity in the last few years, mainly due to the soaring difusion of social networks and internet bots as means for propaganda and disinformation sharing. By leveraging various explainability methods, i.e. feature importance, partial dependence plots and SHAP values, we aim to show how the combination of diferent techniques embedded in an interactive user interface can lead to enhance trust in a detection system for a non-expert user, such as a fact-checker or a content manager. Through several examples, we describe all the explainability components along with the benefits and limitations they can provide to end users.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The concept of fake news has become extraordinarily familiar in the last few years, mainly
due to the common idea of using social networks as an influential source to retrieve news.
Ignoring the recent pandemic period, this expression reached the peak of its popularity during
the historic 2016 US elections, where according to several studies (e.g. [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]), the elected president
Donald Trump gained an advantage by disseminating unverified misinformation and propaganda
through social media. As a consequence of that unusual scenario, the term was appointed
as “word of the year” in 2017 by the American Dialect Society, which defines fake news as
“disinformation or falsehoods presented as real news or actual news that is claimed to be untrue”1.
      </p>
      <p>
        Moreover, the advent and rapid difusion of internet bots (simply known as bots) in social
media [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] have added new perspectives to the already long-standing disinformation problem.
Bots are nowadays massively present on the web and often dificult to recognise. In 2019, a
LGOBE
(E. W. De Luca)
https://erasmopurif.com/ (E. Purificato); https://ernestodeluca.eu/ (E. W. De Luca)
      </p>
      <p>
        © 2022 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
CEUR
Workshop
Proceedings
study conducted by Liu [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] reported that ca. 17% of Twitter accounts are suspected to be bots,
contributing to ca. 30% of the number of tweets posted. In addition to that, the use of bots can
help spread fake news at a faster rate than any human user can. Considering that every single
day ca. 500 million tweets are published2, it is evident how reliable tools for detecting potential
fake news are needed.
      </p>
      <p>Currently, fact-checkers and content managers can make use of existing automated systems
trained on a standard manually-tagged corpus, but this is not suficient for several reasons. First,
in order to keep up with continuously emerging fake news, a huge corpus of facts would be
needed for cross-checking. Secondly, not all fake news is equal: some news entries are entirely
fabricated, while others are built upon facts and injected with deceitful fake content or distorted
and decontextualised opinions. Given this context, it is of paramount importance to design and
develop automated systems able to detect the specific factors that distinguish the fake parts
of an article from the rest. Since such factors have to be checked by content managers to be
deemed false, the resulting decisions must be transparent and interpretable.</p>
      <p>In such a scenario, the design and development of explainable user interfaces (UIs) play
a fundamental role in providing the proper explanations to the end-users, even more than
implementing the system itself in many cases [4]. Much research is being done in several fields,
such as recommender systems [5] and responsible artificial intelligence [ 6], and also a new line
of research is investigating the topic of adaptive and personalised explainable UIs [7].</p>
      <p>In this paper, we present the development of an explainable UI for a fake news detection
system, which can help users understand what parts of the analysed article are likely to be
fake and for what reasons. Through the implementation of feature importance and post-hoc
methods, we show how diferent explainability approaches can be combined and embedded in a
UI to increase non-expert users’ trust in such a system.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Work</title>
      <p>With the described spread of fake news in our daily life due to the constant use of social media,
a lot of research has been produced to find the specific characteristics of disinformation articles
to apply strategies for detecting them and stopping their distribution. Initially, the proposed
tools dealt with manual fact-checking methods, and one of the most popular is Truth-o-Meter 3.
Focusing especially on political news, it classifies news into six groups, considering diferent
degrees of truth. Another famous resource in this direction is Snopes4, which adds the analysis
of images and videos to any trending news, not only politics.</p>
      <p>Currently, more and more automatic detection systems are emerging, and Conroy et al. [8]
presented an in-depth comparison between manual and automatic approaches. Several diferent
types of techniques are exploited for building an automated fake news detection system. Shu
et al. [9] show how to leverage diferent linguistic features extracted from an article’s content,
while other contributions make use of semantics and discourse features (e.g. [10, 11]). More
recent works tried to analyse writing style aspects to unravel bias, such as [12], or to focus on</p>
      <sec id="sec-2-1">
        <title>2https://www.internetlivestats.com/.</title>
        <p>3https://www.politifact.com/truth-o-meter/.
4https://www.snopes.com/fact-check/.
knowledge-based features to enhance the credibility of the system, for example by utilising an
external database for fact extraction and verification [ 13].</p>
        <p>As in most research fields related to artificial intelligence (AI), the state of the art of fake
detection is constituted by systems leveraging deep learning (DL) architectures. Zhang et al. [14]
introduce the concept of dual emotion features in their neural network model to improve the
performance by taking into account the relationship between the emotions depicted in the news
and users’ emotions expressed in the comments. A graph neural network-based approach to
analyse the propagation behaviour of fake news has been proposed by Kipf and Welling [15].</p>
        <p>Despite the proliferation of methodologies, in the illustrated works, the elements for
transparent and explainable systems and related UIs are almost missing or at least latent. According to
Ha et al. [16] and Zhou et al. [17], due to the coexistence of fake and real news, it is necessary to
incorporate the vision of the audience, and this can be achieved via explainability. Shu et al. [18]
propose dEFEND, a system that uses a deep hierarchical co-attention network to represent the
textual features. The network is also used to discover relevant sentences in the articles and
the subsequent users’ comments responsible for detecting them as fake news. We use this
sentence-level explainability feature in the presented work. Yang et al. [19] exploit attributes,
semantics and linguistics for the proposed detection system, called Xfake. In this case, the
explainability aspect derives from self-explainable features aided by visualisations, which also
serve as the basis of our detector’s explainability module.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Components of the Fake News Detection System</title>
      <p>We illustrate the design of the fake news detection system, whose logic architecture is shown in
Fig. 1, by briefly describing its components with a specific focus on the explainability component,
which constitutes the basis for the core part of this paper, i.e. the explainable UI, presented in
detail in the next section.</p>
      <p>The system is designed with a cascading architecture composed of three main phases:
1. Feature extraction: low-level and high-level features are extracted from the fake news
corpus and provided to the connected classifier. The datasets exploited as sources to extract
the features are: the ISOT Fake News Dataset5 provided by the University of Victoria,
the Fake News Dataset6 by Kaggle, the Fake News Corpus7, the Multi-Perspective Question
Answering Dataset (MPQA)8 and the Myers-Briggs Personality Type Dataset (MBTI)9.
2. Classification : leveraging the extracted features, a classifier is applied to the documents
to produce the probability of how likely the analysed news is fake or real.
3. Filtering: based on the resulting probability and the related confidence level of the classifier
that receives low-level descriptors in input, each news is filtered and marked as fake,
real or uncertain. For the latter group, a deeper classification making use of high-level
descriptors is applied.</p>
      <sec id="sec-3-1">
        <title>5https://www.uvic.ca/ecs/ece/isot/datasets/fake-news/index.php.</title>
        <p>6https://www.kaggle.com/datasets/jruvika/fake-news-detection.
7https://github.com/several27/FakeNewsCorpus.
8https://mpqa.cs.pitt.edu/corpora/mpqa_corpus/.
9https://www.kaggle.com/datasets/datasnaek/mbti-type.</p>
        <p>The overall goal is to develop a system able to reach a high confidence score for each tested
article. For this reason, as mentioned before, two diferent classifiers are used, each leveraging
two diferent types of features:
• Low-level descriptors: basic linguistic features from the article texts and headlines, such
as size, number of grammatical errors, parts of speech and term frequencies;
• High-level descriptors: more complex features detected from the news content with
additional algorithms, like sentiment, entailment, attribution, syntactical structure, tones
and latent topics.
3.1. Explainability Component
The explainability component of the presented detection system incorporates both intrinsic
methods, directly derived from the features extracted from the fake news datasets, and extrinsic
methods provided through quantitative and qualitative approaches.</p>
        <p>Intrinsic methods are related to the self-explainable low-level (and some of the high-level)
linguistic features, which do not need any further processing procedure to be presented to the
end users. For the extrinsic methods, we discuss the two approaches separately.</p>
        <sec id="sec-3-1-1">
          <title>3.1.1. Quantitative explainability methods</title>
          <p>The quantitative explainability methods included in our system are the following:
• Feature importance: it is a widely used method for finding the attributes that contribute
the most towards the classifier’s predictions. In particular, in our work, we adopted the
permutation-based feature importance approach proposed by Altmann et al. [20]. This
method improves the interpretability of the results by enabling the users to understand
what are the most influential features for a specific outcome. Furthermore, it can help
build trust in non-experts by allowing them to validate the facts. For instance, if an article
is predicted as fake because of its attribution to a fake source, one can cross-check this
information by directly analysing the pointed source.
• Partial Dependence Plots (PDP): this method was proposed by Goldstein et al. [21] and aims
to create a link between the target label (in our case, fake or real) and the attributes utilised
by the classifiers (i.e. low-level and high-level descriptors). PDP is a model-agnostic and
global method, meaning that it can handle any machine learning algorithm and all the
derived observations are considered while presenting the final output. PDP plots display
how a prediction changes by altering the value of a single feature. Since not all features
afect the final outcome, this method is applied only to the descriptors with the maximum
feature importance score.
• SHapley Additive exPlanations (SHAP): presented by Lundberg and Lee [22], this is one of
the state-of-the-art techniques for explainability, and it is mainly used to figure out the
efect of each attribute of a classifier’s prediction. It is based on the concept of Shapley
values [23], derived from games theory, and considers the reproduction of the prediction
as a game and the input attributes as the players. We make use of the contribution plots
obtained by the SHAP values, wherein we display the contribution of all the attributes
towards its prediction for each observation.</p>
        </sec>
        <sec id="sec-3-1-2">
          <title>3.1.2. Qualitative explainability method</title>
          <p>The implemented qualitative explainability method involves merging the classification
predictions with the extracted features and the results of the quantitative explainability techniques.
To clearly illustrate this concept, we provide some examples. Fig. 2 show an excerpt from a news
article by The Indian Express entitled “Monkeypox virus could become entrenched as new STD in
the US”10. The figure demonstrates how attribution features can be used to aid explainability. A
sentence is highlighted and coloured according to the predicted category. In this case, the red
colour means that the sentence “Experts don’t agree on the likely [...]” has been attributed to
the reported sentence from a fake article published in a known disinformation source called
AmericaBlog.com. Furthermore, the similarity score feature is exploited to weigh the sentence.
The higher the similarity between the targeted sentence with the attributed source, the darker
the highlighting colour.</p>
          <p>In Fig. 3, we show the explanations made by the entailment and sentiment features with
SHAP plots. Through the analysis of the sentence “What a great movie!...if you have no taste.”,
in the provided example, we can see which part of the sentence is responsible for the statement
being contradictory (Fig. 3a) or having a positive sentiment (Fig. 3b). However, the models
could not capture the sarcasm in the sentence, which would have made the sentence more
likely to have negative emotions. This example shows how we can enable system transparency,
giving the end user a chance to validate the predictions, and it can also be used by a developer.
10https://indianexpress.com/article/world/monkeypox-virus-could-become-entrenched-as-new-std-us-8046596/.
Although the sentence is labelled as having a positive emotion, it is clear to the reader that it is
a sarcastic sentence that is not captured. This can point us toward what other techniques can
be experimented with to overcome the limitations.
(a) Entailment score resulting as a contradiction. (b) Sentiment score resulting as a positive emotion.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Explainable User Interface</title>
      <p>In this section, we describe the elements composing the explainable user interface, designed to
provide end users with the possibility to upload a document and get all the information about
the prediction of the fake news detection system, as well as the motivation behind it. As visible
in every image displayed below, we developed the first version of our UI with a Harry Potter
style, starting from the idea of a wizard revealing the truth or the lies in the analysed article.</p>
      <p>When opening the application homepage, a user can choose between two input options for
querying the detection system:
1. Insert the URL of a publicly available article (Fig. 4a);
2. Type manually the text to analyse (Fig. 4b). The second option can be useful to evaluate
only a piece of news instead of the entire body, but we discourage this practice since the
implemented fake news detection system could reveal important information about its
truthfulness from the whole content.</p>
      <p>(a) URL input
(b) Custom text input</p>
      <p>We illustrate the UI components by considering, as an example, an article from bbc.com
about the recent Ukraine war11. Note: Due to the delicate situation regarding the topic at hand,
it is very important to specify that the intent of this paper is not to assess the correctness of the
prediction of the fake news detection system (as it is still under development) but only to show how
the explanations can be assembled efectively in a user interface.</p>
      <p>After clicking on the Revelio button, the pipelines described in Section 3 start. At the end of
the computation, the user lands on the result page shown in Fig. 5.</p>
      <p>The page presents at first the prediction of the detection system in the top left-hand corner,
coloured according to the resulting label (in this case red, because the article has been predicted
as fake). To the right of the result, we can read the confidence of the prediction for the system
(i.e. 78.33%) and the landing pipeline for the classification. Pipeline-2 means that the fake news
detection system, after the filtering step described in Section 3, needed to exploit also high-level
descriptors in order to reach a consistent confidence score.</p>
      <p>By clicking on Show Real and/or Show Fake, the sentences contributing to the real and/or
fake predictions are highlighted in the displayed text, as shown in Fig. 6.</p>
      <p>(a) Contributions to fake prediction
(b) Contributions to real prediction</p>
      <p>As already seen in Fig. 2, the colour gradient relates to the similarity score between the
specific sentence and the attributed source, which becomes visible by hovering over the text
corresponding with a highlighted sentence. Examining the fake contributions in Fig. 6a, we
can see in Fig. 7a that the statement “But I think that what is happening in Ukraine is terrible” is
labelled as strongly fake because of the attribution to a very similar phrase (i.e. “But what is
happening in Ukraine is horrible”) from a known fake news source.</p>
      <p>On the right-hand side of the result page, users can check the list of the most influential
feature contributions towards the overall prediction. The arrows next to each feature name
indicate how strong the contribution of that feature is through their number (from one to three),
as well as their direction (i.e. green up arrows for real, red down arrow for fake). When hovering
over a feature name, a popup appears showing the exact value and a short description of the
selected feature, as shown in Fig. 7b.</p>
      <p>(a) Attribution result
(b) Feature description</p>
      <p>The last functionality proposed in the presented explainable UI is an in-depth analysis of a
single instance. By clicking on the More Explanation button (close to the Show/Hide Fake one),
we land on a new page showing the importance score, i.e. SHAP values, of all the features used
by the classifier for that particular input. This visualisation element is developed by making
use of the ExplainerDashboard tool12, and it also contains two additional tabs. One is for the
visualisation of the partial dependence plots, while the other, called “What If...”, allows the user
to play with the features and adjust their importance score to see if the prediction changes, in
a counterfactual scenario. Since our aim is to address this tool to fact-checkers and content
managers, through this functionality, they can even remove the features considered useless from
the displayed list and check how the result and the related explanations change accordingly.
12https://explainerdashboard.readthedocs.io/en/latest/.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Discussion</title>
      <p>As presented in the previous section, we designed and implemented an explainable UI to provide
an overview of how the developed fake news detection system behaves across the whole dataset
as well as individual instances. In particular, we have given some explaining information, such
as the sentences attributed to being fake or real, the four most important features used for
classification, and a three-level scale of importance. With the latter, we mostly want to provide
an end user, who could be a non-expert, the possibility to check the news for their reliability by
giving them hints about parts of the news to look out for and which might be trustworthy.</p>
      <p>One of the most interesting areas a fact-checker or a content manager can investigate in
the dashboard is the overall model behaviour of the model in terms of the features used for
classification. In Fig. 9, we restricted the figure to only displaying the ten most important
features, which are calculated using the average of all SHAP values across the whole test set.</p>
      <p>The described visualisation element does not provide any insight into how exactly a document
is classified. For that, we can make an individual feature importance analysis per article. We
discuss below an example of a wrongly classified entry by analysing possible reasons to manually
check the system result.</p>
      <p>The article taken into account is entitled “Israeli forces shoot dead Palestinian man in northern
West Bank”13 and is an evident fake news document. However, our system detected it as real
with a 78.3% confidence score. Fig. 10 shows that the most important characteristic is the
text structure (denoted as markov_pred, i.e. whether it is more similar to fake or real articles)
resembling a real article. Additionally, the article is detected as being about the environment
and health, whereas the sentence preceding the health topic must be real. Of course, the article
is neither about the environment nor about health. However, it is probably detected as the latter
due to the text talking about critically injured, wounds, and so on. Very few sentences are only
attributed to being fake, and most text is written neutrally.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion and Future Work</title>
      <p>The presented paper describes the implementation of an explainable user interface for a fake
news detection system designed with a cascading architecture and exploiting both low-level
(basic linguistic features extracted from the content) and high-level (complex features computed
by additional algorithms, like sentiment and attribution to external sources) descriptors. The UI
is composed of several explainability elements related to feature importance, partial dependence
plots and SHAP values. On the result page, a user can check the entire text with information
related to the system prediction, the most influential features ranked by importance, as well as
the sentences that have been attributed to either fake or real sources.</p>
      <p>As the next steps, we aim to finalise the development of the detection system and execute a
robust evaluation of the two classification pipelines, as well as the explainable user interface.
We will also insert more explainability components in the UI, such as text plot for SHAP on
entailment and sentiment features.
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