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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Knowledge Graph of Values across Space and Time</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Martin Ruskov</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Maria Dagioglou</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marko Kokol</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stefano Montanelli</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Georgios Petasis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Institute of Informatics and Telecommunications, NCSR “Demokritos”</institution>
          ,
          <addr-line>15310 Athens</addr-line>
          ,
          <country country="GR">Greece</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Università degli Studi di Milano</institution>
          ,
          <addr-line>20100 Milan</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2000</year>
      </pub-date>
      <abstract>
        <p>The moral values present in classical texts are only implicitly codified and are a form of intangible cultural heritage. In this paper, we focus on capturing the perceptions of these references of values, with the aim to study how they evolve over space and time. To this end, we present our approach that consists of a meta-model and two intertwined design processes for the creation of a knowledge graph capable of capturing an integrated representation of both values and perceptions. In particular, we illustrate how the input collected from diferent activities with the general public can feed the graph to represent multiple and possibly divergent perceptions of values in classical texts. Our meta-model allows for the integration of data from both established scientific techniques such as expert annotations on the one hand, and on the other from standard tests, social media activity, visual representations and games. The proposed approach gives practical means to make explicit both historical and current perceptions of values in classical works of art. Our approach and the resulting knowledge graph enable the comparative analysis of values and their perceptions over space and time.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;intangible cultural heritage</kwd>
        <kwd>citizen curation</kwd>
        <kwd>values across space and time</kwd>
        <kwd>knowledge externalisation</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The moral values present in classical texts are an important part of our intangible cultural
heritage, and in particular when studying a common European identity. Yet, being only implicitly
codified in artifacts, in diferent regions and diferent time periods (what we refer to as “over
space and time”) the perceptions of these values diverge [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. We propose a way to formalise,
and thus make explicit, such perceptions by integrating them in a single knowledge graph,
thus facilitating their comparative study. In the VAST project we focus on the core values of
the European Union. Accordingly, we pursue two goals: i) to make explicit (i.e. externalise)
values implicitly present in literary texts from the past; and ii) to digitise values as they are
perceived by the general public today. In particular, we focus on studying the transformations of
values from three important periods in European history, which we call VAST pilots: Pilot 1: from
Ancient Greek tragedies to modern theatrical plays, Pilot 2: from 17th century works of natural
philosophy to exhibits in science museums, and Pilot 3: from traditional fairy tales across
Europe to contemporary narrative.[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] In this respect, a key objective of the VAST project –
that is reported in this paper – is the construction of a knowledge graph where diferent and
potentially conflicting interpretations about the considered European values are represented
and coexist.
      </p>
      <p>
        As a way to moral values, we take as a reference the definition of Schwartz’s basic human
values, defined as “trans-situational goals, varying in importance, that serve as guiding principles
in the life of a person or group.” His refined theory of values [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] features 19 values. These are
clustered in four universal value dimensions: Self-enhancement, Self-Transcendence, Openness
to Change and Conservation. Schwartz’s framework is widely adopted, e.g. in the European
Social Survey [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and the making of EU policy [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], as well as in various fields including automatic
values extraction from natural language [
        <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
        ]. A particularly relevant recent development is
ValueNet [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], an ontology relating Schwartz’s values to established semantic frameworks like
FrameNet and DBpedia. However, while the proposed model and integration are an important
cornerstone towards formalisation of values, the authors stop short of the actual population of
a semantic knowledge graph. Arguably as a consequence, they do not address the challenge
related to diferent perceptions of values that is the focus of our work presented here.
      </p>
      <p>The knowledge graph proposed here features four major aspects of user interactions with
values present in a historical artifact: i) the participant’s individual characteristics such as
demographics or expressed beliefs (who), ii) the description of the artifact and experience that
define the interaction ( how), iii) the collection of the expressed perceived values (what), and
iv) the spatio-temporal context of the interaction (where and when).</p>
      <p>Next in this paper we review previous research, both in terms of representation of relevant
knowledge, and collaborative knowledge graph creation. In Section 3.1 we present our
conceptual model and knowledge graph engineering process. This is followed by examples of
concrete knowledge externalisation activities and details about our technical implementation.
We conclude with</p>
    </sec>
    <sec id="sec-2">
      <title>2. Background</title>
      <p>
        The two relevant fields of research are works about formalisms and models for representation of
knowledge in the humanities, as well as collaborative methodologies for knowledge graph
engineering. An important role in the crossroads of the two is the already mentioned ValueNet [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
While it does provide an important ontological foundation for the representation of values, it
does not yet address the issue of perceptions of values, which could be divergent across space
and time. Thus, we see it as complementary to the work presented here.
      </p>
      <sec id="sec-2-1">
        <title>2.1. Representation of Humanities Knowledge</title>
        <p>
          When looking for ways to represent historical interpretations, another natural candidate could
be the CIDOC Conceptual Reference Model (CRM). It features elements to allow for the
representation, integration, mediation, and interchange of documents and scientific activities [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. Yet,
formal models like ValueNet and CIDOC-CRM inherently assume an absolutist epistemology,
where knowledge is universally established, and the challenge is to merely represent it [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ].
While CIDOC-CRM does allow for “subjective opinions and inferences”, it falls short of
addressing cultural interpretations and diferences that might lead to possible conflicting ontological
constructs [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]. Such an epistemological perspective is too restrictive when working with
intangible concepts and the critical approach commonly used in the humanities [
          <xref ref-type="bibr" rid="ref12 ref13">12, 13</xref>
          ]. This typical
pluralism of interpretations highlights the need for a less absolutist and more culturally-aware
representation of social constructs such as values. An established epistemological foundation of
such a formal representation is social constructivism, where knowledge is understood to stem
from shared interpretation and understanding. This leads to the idea that ontological entities
are grounded in a particular socio-cultural context. A constructivist approach is taken e.g. in
PhiloSurfical [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] in the construction of their ontology of philosophy. The authors argue that
they cater for diferent interpretations by modelling the ontology at a high level of generality,
thus making their representations “as re-usable as possible, especially among annotators having
diferent philosophical views”.
        </p>
        <p>
          Beyond the aforementioned limitations, for the formal representation of values, we note that
CIDOC-CRM supports the appellation relationship that can be employed for a simplistic to
representation between concepts (as used in VAST) and their corresponding terms. The authors
of the PhiloSurfical model [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] introduce the notion of idea-appelation to denote philosophical
concepts. As a further contribution, the Europeana Data Model has been recently proposed to
represent cultural-heritage resources by adopting the Simple Knowledge Organization System
(SKOS) and thus also addressing possible definitions of of concepts [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ]. Similarly to
CIDOCCRM, SKOS itself is a schema, but it hosts a number of thesauri that contain entities that could
be useful as terms in our approach. Noteworthy are the GESIS Thesaurus for the Social Sciences1
and the UNESCO Thesaurus2.
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. Collaborative Knowledge Graph Engineering</title>
        <p>
          When multiple contributors are involved in the specification of an knowledge graph, a clearly
deifned process becomes a necessity. The NeON methodology framework to collaborative ontology
engineering provides variations of a process to be used in diferent circumstances, depending
on planned project duration or availability of pre-existing knowledge resources [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]. The
simplest among these is a flow of four subsequent steps to align contributors: initiation, design,
implementation, and maintenance. Other versions also include reuse, merge and re-engineer
phases, or an iterative repetition of the process. Particularly relevant here is the NeON
iterativeincremental approach that consists of iteratively repeating the stages of the simple process.
Special attention is paid to ensure that no backtracking takes place so that the process converges.
1https://www.gesis.org/en/services/research/thesauri-und-klassifikationen/social-science-thesaurus.
2https://skos.um.es/unescothes.
        </p>
        <p>As an alternative, the UPON Lite framework consists of 6 steps identified by their objectives:
terminology, glossary, then taxonomy, predication and parthood performed in parallel and,
ifnally, ontology [ 17]. These steps can be considered as a detailed expansion of the design and
implementation phases in NeON.</p>
        <p>The idea of involving non-expert users in ontology engineering has been discussed in the
literature by proposing to employ crowdsourcing-based solutions. Daga et al [18] consider how
citizen are contributing to cultural heritage archives. However, none of the considered examples
are addressing the need to organise diverse knowledge in a single knowledge graph. Highly
structured software for ontology construction and crowdsourcing from social networks has been
used as a validation mechanism [19]. Games with a purpose (GWAP) have been also proposed as
a common solution to employ crowdsourcing contributions for the creation of knowledge graphs.
These have been categorised into four types: specification of term relatedness, verification of
relationship correctness, specification of relation type, and verification of domain relevance [ 20].
An example of specification of term relatedness is Free Association [ 21], in which given a word,
the user is asked to find others that are related. A recent example for relationship verification is
Indomilando [22] where players are asked to choose between diferent predefined relationships
in the form of multiple-choice questions) as a way to verify that an undisclosed one of them is
correct. A typical model for specification of relationship type is a game called SpotTheLink [ 23]
where players are given two concepts and asked to identify a relationship that could connect
them.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Approach</title>
      <p>We describe our participatory knowledge graph design providing two overarching perspectives,
one static describing the meta-model and one dynamic describing the process of knowledge
externalisation.</p>
      <sec id="sec-3-1">
        <title>3.1. Knowledge Graph Meta-model</title>
        <p>Starting from the tangible artifacts and the users interacting and interpreting them, we develop
a representation of the activities and the elicited values. This is reflected in the four principle
domains of Figure 1 and discussed below.</p>
        <p>Artifacts. The knowledge graph that we present here features a unified representation of
tangible resources, from historical documents and pieces of art to questionnaires and activity
recordings. A common feature of the representation of all these is their association to a
specific spatio-temporal context. Whereas to the knowledge graph artifacts are simply stored
objects, some of them might also have a role in the knowledge graph creation as structural
representations of knowledge, including annotations, questions and answers or digital games
provoking particular behaviours, as elaborated in Section 4. Correspondingly, to be able to
facilitate a focused reflection or discussion of a particular part of an artifact, the knowledge
graph features also a representation of a segment of an artifact, be it text, video or a more
structured digital tool.</p>
        <p>Group metadata
- composition (number) - nationality composition
-- aggeendceormcpoomspitoiosnition -- cmuolttuhrearltpornegfeureenccoemsposition
- education composition - school data (optional)
(0,N)
(1,1)
User
(0,N)</p>
        <p>(1,N) Group
(0,N) (0,N)
(0,N) (0,N)
(1,1) (0,N) Activity
(0,1) (0,1)
(0,N)
Event</p>
        <p>(0,N)
Context
Terms
VAST
keywords
Audio
Video
Image
Tools
Document
(0,1) Statement</p>
        <p>(0,N)
(1,1)
(0,N)
((01,,N1)) C(0o,nNc)ept
(0,N)</p>
        <p>Relation
(0,N) Profile (0,N)</p>
        <p>(0,N)
Schwartz
value
(0,N)
(1,1) (0,N)</p>
        <p>Artifact (1,1)
(0,N)
Blobs
(0,N)</p>
        <p>Questionnaire Interview
(1,N)</p>
        <p>MindMap
(1,1) (0,N)
(1,1) Segments</p>
        <p>(1,1)
Annotation
(1,1)</p>
        <p>Expert
User metadata
- name
- age
- gender
- education
- nationality
-- cmuolttuhrearltpornegfeureences
Non Expert
Supportmaterials
(0,N)</p>
        <p>Step
(0,N)
(0,N)
(0,N)</p>
        <p>Stimoulus
Activity metadata
- date
- event
- description
- nature (online, in person)
- tongue
ACTIVITY REPRESENTATION
Users. To capture their perceptions of values over space and time, our knowledge
representation features two types of users as represented in Figure 1, who could contribute diferently:
(i) Expert users include humanities researchers that study and interpret the historical intentions
behind an artifact, social science researchers that study current perceptions of it and value
communicators that reenact its contemporary significance. This separation of responsibility
needs not be strict, but the contribution of each user has a clearly defined spatio-temporal
context, which for expert users is their domain of expertise, as further explained in the Section 3.2.
(ii) Non-expert users are the general audience participants that engage in VAST activities and
share their perceptions and views. Based on an experience (activity) related to a historical
artifact. This could happen in a museum or theatre visit, in a school activity or online, which
defines their corresponding spatio-temporal context.</p>
        <p>
          Activities. Users engage with artifacts in the context of particular activities that also need
to be represented in the knowledge graph. This is not only due to the need to store the time
(technically – date) and space (geolocation) of when and where these take place, but also their
structure. In order to capture the potential influences that might shape the user experience,
its steps (i.e. method) and stimuli (i.e. artifacts used as supplementary materials) are being
represented. This allows the knowledge graph to relate responses to stimuli from diferent steps
within a single activity, even when the related data is collected in anonymised form. Finally, the
context of the activity is represented through the recordings of activity sessions (i.e. events),
involved organisations, and individual and/or group demographics. Providing an example for a
complete activity is out of the scope of this paper. Instead, here we take a data-centric approach,
focusing on representation and collection of data. Accordingly, in Section 4 we provide examples
of diferent types of used artifacts and the corresponding digitisation of concepts.
Concepts. To represent values, the VAST knowledge graph features two main entities:
concepts and terms. Concepts, a core part of which are the Schwartz values, are abstractions that
could feature also other commonly established psychological constructs beyond those studied
by Schwartz. By adopting standard psychological instruments, such as the European Social
Survey [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] (a type of artifact for our knowledge graph) in activities, these concepts are associated to
user profiles. As already indicated, values – and concepts in general – are implicitly represented
in communication across diferent media (e.g., text, visual arts, drama, oral narration). As
communication changes in diferent social contexts, so does the perception of underlying values. As
a consequence, we consider terms and concepts to be omnipresent across space and time, but we
consider relationships between them to be related to a specific context, thus pinned to specific
time and space. Terms represent explicit categories, each defined by a label and associated to
diferent artifacts. The vocabulary of terms includes the values of the EU and an expert-led
expansion of these, termed VAST keywords, but potentially also other terms introduced by users.
Terms are associated to annotations in artifacts by users (expert and non-expert, as detailed in
Section 3.2). Concepts and terms are variously interconnected by relationships. In particular,
a binary relationship among a pair of terms/concepts can be specified to denote a semantic
relation holding between them. Three particular relationship semantics have been identified as
relevant: has-broader-term (semantically equivalent to P127 in CIDOC CRM), shows-features-of
(P130), and is-in-conflict-with (no CIDOC CRM equivalent).
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Knowledge Graph Engineering</title>
        <p>
          Our approach to knowledge graph engineering is based on an iterative-incremental design
approach inspired by the NeON methodology [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ] and the UPON Lite methodology. NeON in
a sentence. UPON Lite has been defined to “ shift responsibility for ontology building toward a
community of end users through a social, highly participative approach supported by an easy-to-use
method and tools [17]”.. In the first stages of the process, experts collaboratively create the
core of the knowledge graph. For each VAST pilot, a team of domain experts composed of
researchers and value communicators works to produce vocabulary (i.e. terms and concepts)
and relationships, relevant to the pilot. In this respect, the following sequence of steps have
been defined.
        </p>
        <p>Vocabulary definition. Starting from EU values, experts from the three pilots define an
extended set of terms that they consider relevant to their respective domain, both spatio-temporal
and in terms of activities. A single vocabulary of terms and concepts is defined containing the
whole set provided by all pilots, so that a term can be used where found appropriate regardless
of the activity in which it emerged.</p>
        <p>Schema definition. As explained in the previous subsection and shown in Figure 1, a general
schema has been defined beforehand. Beyond that, the decisions of how to represent individual
artifacts and activities, as well as how to connect these terms are taken by the core team of
domain experts representing each of the three pilots.</p>
        <p>Schema population. The content generation is reduced to micro-tasks doable within single
isolated sessions, in which users are assumed not to have prior awareness and need to be
introduced to the entire context. Thus, these sessions (i.e. activities) are much closer to field
studies in museums, theatre, schools or particular online settings. They represent a highly
structured way of schema population akin to citizen curation [18] and games with a purpose [20]
designed by domain experts. Particular examples of activities including such micro-tasks with
non-experts have been presented elsewhere [24, 25, 26] and an illustration of the corresponding
integration of the data in the knowledge graph follows.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Digitisation Samples</title>
      <p>Our approach allows for the integration of a wide range of user contributions into the knowledge
graph as a way to formalise contributor knowledge. To illustrate this, here we discuss five
distinct examples that illustrate the full range of structured and unstructured contributions.
These are text annotation, questionnaire responses, dedicated social network discussions about
values, mind map creation and digital game interactions.</p>
      <p>Text Annotation. An established content analysis technique is used to annotate values in
classical texts with dedicated annotation tool and methodology [27]. In particular, we work on
English translations of the considered textual artifacts and users are asked to identify segments
in artifacts and tag them with (one or more) appropriate terms from the vocabulary. In contrast
to other activities described below, text annotation is a lengthy process that requires longer
periods of engagement, but is also accessible to experts. Users are first asked to annotate explicit
references to the considered values in the artifact. Then, they are asked to annotate implicit or
indirect references to values, according to their subjective interpretation.</p>
      <p>
        Questionnaires. Three models for mapping answers of common question types to the
knowledge graph are supported, namely multiple choice questions, scale questions and open-answer
questions. Multiple choice questions allow for formulation of questions aimed specifically at a
particular set of alternative relationships, be it between terms, concepts, profiles , artifacts, etc.
An example of such a question regarding the relationship between a segment of an artifact and
a term is provided in Figure 2. These questions can typically be formulated to enquire about
relationships proposed by experts and allow probing for their perceived validity across various
user groups. Scale questions allow to examine the strength of relationships, for example using
Likert-scale questions of standardised questionnaires from psychology [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. This allows adding
a quantitative measure to the relationships provided by an individual. To this end, beyond the
information about the relationship supported by the user, also knowledge graph statements
containing the question scale and the response rating are stored. Finally, open questions allow
for unconstrained free-text responses. We propose two distinct ways to integrate these in
the knowledge graph. One is to pose questions that provide two of the elements of the triple
representing a relationship in the knowledge graph. Then users are asked about the third as
illustrated in Figure 2. With this approach, a statement for the response is included in the
knowledge graph only for those responses that can be automatically mapped (e.g. via exact
matching to possible appellations) to preexisting objects. Answers that are not reduced to
preexisting statements in this way are simply included as new artifacts for future qualitative
analysis. Such addition as artifacts is the second (and non-automatically interpretable with
the current functionality) way to integrate answers to any form of open questions into the
knowledge graph. This is necessary because questionnaires have been designed beforehand
without considering digitisation constraints.
      </p>
      <p>Social Network Activity. Using the specific functionalities of social networks, such as polls,
images and replies, questionnaire items can be represented online to reach wider audience,
as shown in Figure 2. Posting such questions with specific hashtags or in dedicated groups
provides a community context remotely similar to the one of a bespoke activity, albeit with
limited demographics data.</p>
      <p>Mind maps. Another widespread technique to collect opinions, that is both an intuitive
representation of complex knowledge and naturally adapts itself to a knowledge graph, is
network-based visualisations such as mind maps, and the similar concept maps and topic maps.
Such data is being collected in a range of activities within the VAST project (see Figure 3), both
on paper to be curated and digitised by educators, and in a dedicated digital tool that allows data
to be directly imported in the knowledge base. Typically in such activities, students are asked
to start from a concept or term present in the knowledge graph and – in a group or individually
– expand the map with their own views. The nodes that are being introduced in the process are
either mapped to terms with coinciding labels, or introduced as new terms [24]. A particularity
of this type of activities is that more often than not, relationships are unlabeled. In such cases,
we employ a general relatedness (shows-features-of) relationship.</p>
      <p>Digital Game Experiences. Yet another very broad category of activities are bespoke digital
games that provide highly structured experiences and are designed to generate specific
representations of player perceptions based on their choices within the game. Two examples that
have been developed within the VAST project and shown in Figure 4 are games where players
are asked to role-play the Little Red Riding Hood and The trial of Antigone [25, 26] and value
preferences are being derived from the player choices within the games.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Technical Implementation</title>
      <p>The VAST platform is built on top of a GraphDB instance which ensures a RDF-compliant
storage and a SparQL querying endpoint. This graph database is used as a data warehouse,
synchronised via API endpoints and synchronisation scripts with the various components.
These components include a text annotation tool, a survey management tool, and a set of
digitisation tools for diferent activities. Beyond the specific bespoke integration with the digital
mind maps and games, also a generic digitisation tool which allows for the import of generic,
including non-digital activities. The resulting integration, including content produced from the
above-mentioned digitisation types, is accessible via the VAST platform3.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion and Future Work</title>
      <p>In this paper we described an approach to the construction of a knowledge graph of moral
values – a particular type of abstract concepts. The necessity to represent both past and present
interpretations of the values conveyed in historical artifacts has led us to consider a broad range
of contributors. We employ an iterative-incremental process. We also demonstrate a range of
mechanisms that engage users to contribute to our knowledge graph.</p>
      <p>The produced participatory knowledge graph is made available via the VAST platform. Besides
supporting both qualitative and quantitative research (e.g. providing baselines for values mining
and natural language processing), this collection of structured datasets can be used for
citizeninformed curation, and design of future museum activities.</p>
      <p>An important aspect of knowledge graph creation is interoperability with other relevant
semantic resources, such as CIDOC-CRM and ValueNet. While not discussed here, this has
been envisioned by trying to reuse semantics as much as possible, e.g. relationship types from
CIDOC-CRM and shared concept entities with ValueNet. Yet, the actual integration remains to
be detailed.</p>
      <p>Furthermore, answer matching in the described approaches could be expanded by identifying
concepts and terms with their corresponding appellations from established thesauri. Beyond
this, answers to open questions could be further analysed for further semantic interpretation,
e.g. identifying responses to generic questions who, how [28], where [29], etc.</p>
      <p>Although it is beyond the scope of this paper, an important aspect of the knowledge graph
design process are the activities that involve contributors. Whether it is questionnaires or
mind map compilation done within conventional museum workshops or self-paced activities in
social networks or games, enriching text content with multimedia is expected to contribute to
engagement and retention. One way to make this more accessible, that has recently emerged,
is through the semi-automatic generation of contextual illustrations. While text-to-image
generator models are not commonly grounded in pre-existing text, preliminary tests have
shown very positive results [30].</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgments</title>
      <p>⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆ This project has received funding from the European Union’s Horizon 2020 research and
innovation programme under grant agreement No 101004949. This document reflects only the
author’s view and the European Commission is not responsible for any use that may be made
of the information it contains.
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