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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>YAI4Edu: an Explanatory AI to Generate Interactive e-Books for Education</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Bologna</institution>
          ,
          <addr-line>Bologna</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Pittsburgh</institution>
          ,
          <addr-line>Pittsburgh PA</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>1902</year>
      </pub-date>
      <abstract>
        <p>In this article, we investigate how explanatory AI can better harness the full potential of the vast and rich library of books at our disposal. Based on a recent theory of explanations from Ordinary Language Philosophy that frames the process of explaining as illocutionary process of answering to questions, we have developed a new kind of interactive and adaptive e-book. Using the most recent question answering technology, our e-book automatically generates a specialized knowledge graph from a collection of books and other resources and extracts questions and answers. With this knowledge graph, the e-book generates interactive and adaptive explanations that guide readers through the materials in a pedagogically productive manner.</p>
      </abstract>
      <kwd-group>
        <kwd>Explanatory Artificial Intelligence Interactive e-book Question answering Knowledge graph extraction Education</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Being able to harness and share knowledge is central to the health and prosperity
of our society. Since the invention of writing, we (as society) managed to gather
together a huge amount of diverse written contents. Nowadays, thanks to recent
advancements in artificial intelligence and computer science, we have the ability
to search through impressive amounts of books for answers or many other types
of information. Nonetheless, fully harnessing the potential of knowledge in an
intuitive and user-centred way is still an open problem.</p>
      <p>For example, different readers might seek and require different types of
information regardless of the fact that a single book has a predefined exposition
and content. This is why different books about the same topic exist, unfolding
the same knowledge in different ways and with heterogeneous levels of detail.
Furthermore, the background knowledge of the reader might vary considerably
so that even the most basic concepts should be explained thoroughly whenever
the reader needs to acquire them or refresh memory.</p>
      <p>Copyright c 2022 for this paper by its authors. Use permitted under Creative
Commons License Attribution 4.0 International (CC BY 4.0).</p>
      <p>These insights lead us to the identification of the following problem. Most of
our educational content (e.g. books) is static, although rich in contents possibly
scattered throughout hundreds of pages, indirectly relying on external knowledge
for the reader to understand. This static type of representation, in the most
generic scenario, is sub-optimal and time consuming for a human reader because
useful information can be either sparse or lacking.</p>
      <p>
        To address this problem we study how to automatically enhance (static)
books making them interactive, thus reducing the sparsity of relevant
information and also increasing the explanatory power of the medium by linking it to
a knowledge graph extracted from a wide collection of related books. To do so,
we exploit a recent theory of explanations from Ordinary Language Philosophy,
framing the process of (interactively) explaining as a process of illocutionary
question answering [
        <xref ref-type="bibr" rid="ref16 ref17">16,17</xref>
        ]. Our work heavily relies on the intelligent interface
design for the generation of user-centred explanations proposed by Sovrano et
al. [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ]. In particular, we extend [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] to make it more adaptive and specific
to education. To summarize, assuming that the goal of an educational e-book is
to explain something to the reader, the technology we are proposing is designed
around the idea that organizing the explanatory space (the space of all possible
bits of explanation) as clusters of questions and answers is beneficial for the
reader.
      </p>
      <p>
        With the present article we briefly introduce YAI4Edu, a first prototype of
Explanatory AI to generate interactive e-books for education, without providing,
for now, any empirical results or in-depth evaluations (besides those already
carried out in [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]).
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        There are studies suggesting that using interactive e-books leads to an increase
in use, motivation, and learning gains versus static e-books [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. In particular,
we have several streams of work on the topic of interactive e-books. Most of
these works seem to focus on the cognitive process of the reader, studying how
to enhance the pedagogical productivity of textbooks through expert systems or
sophisticated interfaces. They usually do it by showing personal progress through
open learner models [
        <xref ref-type="bibr" rid="ref6 ref7">6,7</xref>
        ], or by specialising on ad hoc tasks through some kind
of domain modelling [
        <xref ref-type="bibr" rid="ref3 ref4 ref9">4,3,9</xref>
        ], or by student modelling through questions in order
to identify and suggest personalised contents [
        <xref ref-type="bibr" rid="ref11 ref19 ref9">19,11,9</xref>
        ], or by providing tools for
manually creating new interactive e-books [
        <xref ref-type="bibr" rid="ref12 ref8">12,8</xref>
        ].
      </p>
      <p>In this sense, the use of AI for the automatic generation of interactive
ebooks seems to be under-explored. Differently from all the examples we found
in literature, our approach attempts to fully automatically convert an existing
e-book into an interactive version of it by exploiting theories of explanations and
intelligent interfaces.</p>
    </sec>
    <sec id="sec-3">
      <title>Background</title>
      <p>The goal of this section is to provide enough background information for the
reader to understand what are explanations and the existing metrics to evaluate
explanations.</p>
      <p>
        Achinstein’s Theory of Explanations. In 1983, Achinstein [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] was one of
the first scholars to analyse the process of generating explanations as a whole,
introducing his philosophical model of a pragmatic explanatory process.
According to the model, explaining is an illocutionary act coming from a clear intention
of producing new understandings in an explainee by providing a correct
contentgiving answer to an open question.
      </p>
      <p>
        Definition of Illocution. According to [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ], it is possible to define
illocution in a more “computer-friendly” way as an act that involves informed and
pertinent answers not just to the main question, but also to other (archetypal)
questions of various kinds, even unrelated to causality, that are relevant to the
explanations. Many examples of these archetypal questions are given by [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ],
i.e. why, what, when, who, how, etc.
      </p>
      <p>
        Explanatory AI. An example of intelligent interface based on Achinstein’s
theory of explanation has been discussed in [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ]. These works rely on AI for
knowledge graph extraction, question-answer extraction and question-answer
retrieval. In particular, the explanandum3 is reorganised and represented as a
special hyper-graph where information can be either explored through overviewing
or searched through open questioning. On one hand, overviewing can be
performed iteratively from an initial explanation by clicking on annotated words
for which an explanation (in the form of a cluster of questions and answers
automatically generated by the AI) is needed. On the other hand, open questioning
can be performed asking questions in English through a search box that uses an
underlying knowledge graph for efficient question-answer retrieval.
      </p>
      <p>
        DoX is an algorithm proposed by [
        <xref ref-type="bibr" rid="ref16 ref18">18,16</xref>
        ] that can measure the quality of
explainable information. DoX is a model-agnostic approach based on Achinstein’s
theory of explanations. In practice, DoX can quantify the degree of explainability
of a corpus by estimating how adequately that corpus could be used to answer in
an illocutionary way an arbitrary set of archetypal questions about the concepts
of the explanandum.
4
      </p>
    </sec>
    <sec id="sec-4">
      <title>YAI4Edu: an Explanatory AI for Education</title>
      <p>
        Our proposed solution is called YAI4Edu (meaning Explanatory AI for
Education) and it is an extension of the Explanatory AI used by [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ] to generate
interactive user-centred explanations. More specifically, interaction is given by
word glosses (called overviews ) and a special kind of search box that allows
the reader to get answers about any English question, as described in section
3. In particular, we adapted such Explanatory AI to transform static educative
3 Explanandum means “what is to be explained” in Latin.
      </p>
      <p>
        Fig. 1. Explanatory AI - Landing Page: This figure contains a screenshot of the
annotated textbook and the input for open questioning. The textbook is an excerpt of
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Clicking the underlined words opens an overview.
textbooks (in PDF format) into interactive e-books. To this end, we developed
several AI-based mechanisms for: i) smart annotation generation, ii) adaptive
overviewing, iii) and granular overviewing.
      </p>
      <p>
        Smart Annotation Generation is a mechanism for automatically
annotating a PDF book. Similarly to [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ], these annotations, when clicked, open
an overview (a special cluster of information explaining the annotated word).
Differently from [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ], the mechanism for the identification of which words to
annotate is more intelligent and it relies on DoX. Indeed, our smart annotation
mechanism annotates only those concepts and words that are the most
explainable (i.e., with a DoX greater than a predefined threshold) by the content of
the knowledge graph extracted from the textbook and other related resources.
This annotation mechanism is intended to significantly remove noisy
annotations and distractors, so that the reader focuses only on the most central and
well-explained concepts.
      </p>
      <p>
        Adaptive Overviewing. We improved the mechanism of overviewing
proposed by [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ] in order to support adaptive and more fine-grained explanations.
More specifically, we designed a naive knowledge tracing mechanism that keeps
track of pieces of information previously shown to the reader in order to
filter them and re-organise the content of overviews accordingly. Furthermore, we
changed the ranking mechanism that orders information inside the overview so
that the most explanatory questions are presented first. The degree of
explainability of such questions is computed through DoX as in the smart annotation
generation.
      </p>
      <p>
        Granular Overviewing. Similarly to [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ], the content of the overviews
we use is composed by a set of pre-defined archetypal questions (i.e., why, what,
how, who) about the main topic of the overview. Differently from [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ] though
we consider also more domain specific archetypal questions automatically
extracted from the knowledge graph through an AI specifically trained for
questionanswer extraction. In order to automatically extract pairs of meaningful
questions and answers, we trained in a supervised manner a general-purpose deep
language model on 2 data-sets [
        <xref ref-type="bibr" rid="ref10 ref13">10,13</xref>
        ] composed by tuples of (s; q; a), where s is
a source sentence, q is a question (implicitly) expressed in s and a is an answer
expressed in s. We decided to adopt the T5 [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] technology in order to
combine different tasks (e.g. the extraction of both discourse relations and abstract
meaning representations) within a single language models.
      </p>
      <p>To summarize, assuming that the goal of an e-book is to explain something
to the reader, our YAI4Edu is designed around the idea that organizing the
Explanatory Space (the space of all possible bits of explanation) as clusters of
questions and answers is beneficial for the reader. In figure 1 and figure 2 we
show an example of our Explanatory AI applied to an excerpt of a textbook for
teaching how to write legal memoranda in the US legal system. This textbook is
used in the course of “Applied Legal Analytics and AI” at the University of
Pittsburgh. More precisely, “Applied Legal Analytics and AI” is an interdisciplinary
“joint course, co-taught by instructors from the University of Pittsburgh School
of Law and Carnegie Mellon University’s Language Technologies Institute,
providing a hands-on practical introduction to the fields of artificial intelligence,
machine learning and natural language processing as they are being applied to
support the work of legal professionals, researchers, and administrators”.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Discussion</title>
      <p>The prototype we just presented is the first step towards a more thorough
evaluation of the underlying theory of explanations. The overall hypothesis behind
our work is that explaining is somehow about question answering so that the
more questions a book can answer, the more it explains. In other terms, the
explanatory power of a book can be improved by making it interactive in a way
that helps its readers to identify the most important questions to be answered
and to get answers about their own questions.</p>
      <p>To verify this hypothesis we need an experiment that would show that
students can acquire new knowledge more deeply with an interactive e-book
generated with our enhanced Explanatory AI. Furthermore, we should be able to
verify this on multiple domains and with multiple textbook to claim that our
proposed solution is generic enough and to verify the hypothesis in the most
generic case. An experiment to this end could be the following.</p>
      <p>We identify a population of N students and we give them a normal book
to study and a goal in the form of “Explain in the most detailed way topic T
and anything related to it”. Then we take another population of N students and
we give them the same goal and an interactive version of the book generated
by YAI4Edu. We collect the answers from both the populations and we shuffle
them. Then we give these answers to a professor for the evaluation, in a way that
guarantees that the professor does not know in advance whether a student comes
from the first or the second population. Eventually, if the second population of
students, in average, gets better evaluations than the first population, then we
can say that the hypothesis holds.
6</p>
    </sec>
    <sec id="sec-6">
      <title>Conclusions and Future Work</title>
      <p>
        With this paper we presented a prototype of YAI4Edu, an Explanatory AI for the
automatic generation of interactive and adaptive e-books for education. To create
YAI4Edu we enhanced the Explanatory AI proposed by [
        <xref ref-type="bibr" rid="ref15 ref17">15,17</xref>
        ], making it more
adaptive and smart. More precisely, we devised a novel mechanism for selecting
explanatory contents based on DoX [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] and a naive strategy for knowledge
tracing. Such strategy we adopted for knowledge tracing is extremely naive and
it should considered only as baseline whereas more sophisticated mechanisms
might be used instead, e.g. FAST [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
      </p>
      <p>As future work, we plan to run the experiment discussed in section 5 on
different textbooks or other educative media used in the context of Law and
Computer Science. Such experiment will consist in a user study focused on
understanding whether the underlying theory as well as the presented prototype of
YAI4Edu are good enough to address the problem of automatically generating
interactive e-books.</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgements</title>
      <p>This work was partially supported by the European Union’s Horizon 2020
research and innovation programme under the MSCA grant agreement No 777822
“GHAIA: Geometric and Harmonic Analysis with Interdisciplinary Applications”.</p>
    </sec>
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