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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Last access:</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Domain Experts' Involvement in Training Conversational Agents</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Stefano Valtolina</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ricardo A. Matamoros Aragon</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Università degli Studi di Milano</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>via Celoria</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Milano</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>stefano.valtolina@unimi.it</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Italy</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Social Things srl</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Milano</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>ricardo.matamoros@socialthingum.com</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Italy</string-name>
        </contrib>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>202</volume>
      <fpage>3</fpage>
      <lpage>05</lpage>
      <abstract>
        <p>In recent years we have seen a significant proliferation of intelligent personal assistant devices in different use domains. If, on the one hand, the number of conversation-based interactions is growing, on the other hand, the design of chatbots able to assist users in complex decisionmaking tasks is still a significant challenge. To this aim, we need to design chatbots that can give final users proper advice to accomplish their goals. In this paper, we propose a strategy that aims to involve domain experts as the only people who, with their competencies, can train the chatbots to provide helpful suggestions. To test our idea, we present two chatbots designed to help teachers create new courses or caregivers define rules for monitoring older people's indexes of active life. In our approach, we ask domain experts to find or write wiki pages describing the learning objects to compose a course or activities to monitor older people's behaviours. Then, the model we defined extracts from the wiki pages the metadata the chatbot will use to filter the learning objects or the monitoring rules to adopt. To finish, we present a few preliminary tests demonstrating comforting indications about our model.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Driven by the success of intelligent personal assistant devices such as Amazon Alexa and Google
Assistant, chatbots are emerging as new interactive solutions in different use domains. Also known as
Conversational User Interfaces (CUIs) or Conversational Agents (CAs), these apps demonstrate
attractive strategies for implementing language-based interactions and delivering a better user
experience (UX).</p>
      <p>
        Based on the work in [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], we can classify chatbot-user interaction according to the intended duration
of the relationship with users (short vs long term) and the locus of control for the dialogue (user-driven
vs chatbot-driven interaction). A short-term relationship characterises user engagement using a single
interaction with the chatbot without aiming for prolonged communication. In contrast, a long-term
relationship focuses on a user's retention, for example, by drawing on the user profile information to
strengthen user experience across visits. Regarding the dialogue, chatbots display different approaches
according to who takes the role of conversation leader. In some cases, the chatbot controls the
interaction by using scripts that include only limited options for branching or alternative paths. In other
cases, the chatbot can reply more flexibly. By identifying the user's intent, the chatbot can assist her/him
and respond adequately.
      </p>
      <p>From a technical point of view, designing a chatbot to support short interactions is relatively more
straightforward. For example, the use of chatbots is becoming commonplace on the websites of
businesses. They help customers find a suitable service or product, answer their questions, and allow
them to make a booking or submit an order. In contrast, if we need to design a chatbot-based long
interaction, we have to deal with more complex challenges, and in this field, the chatbot's potential has
yet to be leveraged.</p>
      <p>In particular, this paper aims to explore how to create chatbots to embed into interfaces used for
complex decision-making tasks. Here, we are interested in developing chatbots that act as assistants or
coaches of users for supporting long-term engagements. Some long-term chatbots exploit the duration
of the relation to gradually present a rich set of content, such as a complex story or a game, or to
gradually build skills and capabilities in the user, such as in educational, fitness or therapy chatbots.</p>
      <p>To maintain conversations with users as long as possible, can happen that the chatbot has to suggest
doing something or making a decision. This conversational recommender facility allows chatbots to
present personalised content through discussions to help users accomplish a specific goal. Strategies to
design this type of chatbot require an interdisciplinary approach that often transcends technology and
focuses on requirements regarding user experience, domain-specific rules and issues. These
requirements can be explained by domain experts who are not technical experts but know the context
of work well and have the competence to train the chatbots to provide helpful suggestions.</p>
      <p>For this reason, we aim to involve non-technical users in developing chatbots and their
recommendation facilities. The proposed approach leverages specific machine-learning techniques to
analyse Wikipedia pages (also named wiki pages), in which domain experts can specify requirements
and competencies that the chatbot can use to formulate its suggestions.</p>
      <p>
        According to these considerations, in the next Section, we present an overview of relevant studies
we used to motivate the adoption of conversation agents in two user domains. The first is a chatbot
integrated with a Learning Management System used to assist teachers in creating digital courses. A
second chatbot has been designed to act as an older people's assistant, providing functionalities to
combat the typical loneliness that can affect their quality of life. Section 3 describes our strategy, based
on End User Development (EUD) [
        <xref ref-type="bibr" rid="ref2 ref3 ref4 ref5">2-5</xref>
        ] techniques that aim to engage domain experts in the training
process of the recommendation service used by the chatbot to facilitate complex decision-making tasks.
Finally, Section 4 sums up conclusions and future works.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. Chatbots to Support Complex Tasks</title>
      <p>
        Exploiting the proposed typology in [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], we identified high-level approaches that led us to design
effective conversations between users and our chatbots. This classification identifies four areas of
interest: Customer service, Personal assistants, Content curation, and Coaching. In detail, in this work,
we are interested in studying chatbots for supporting long-interactions, such as personal assistants and
coaches. These chatbots can help users in their activities by providing suggestions to deal with work
and daily activities and to scaffold human decision-making when it occurs. The design of these
conversations is more challenging, both from a technological point of view and regarding the needed
breadth and volume of content. The chatbot has to identify the user's intent on the level of the individual
messages and overall interaction and respond adequately to these intents. Therefore, we developed two
prototypes, as described in the following Sections.
2.1.
      </p>
    </sec>
    <sec id="sec-3">
      <title>Conversational Agent in Education</title>
      <p>
        The literature presents many studies regarding using chatbots in the educational domain [
        <xref ref-type="bibr" rid="ref6 ref7 ref8">6-8</xref>
        ].
According to the review [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], chatbots are mainly applied for teaching and learning (66%). They promote
rapid access to materials by students and faculty at any time and place [
        <xref ref-type="bibr" rid="ref10 ref9">9,10</xref>
        ]. This strategy helps save
time and maximise students' learning abilities and results [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], stimulating and involving them more in
teaching work [
        <xref ref-type="bibr" rid="ref12 ref13">12-14</xref>
        ]. However, to our knowledge, chatbots are rarely used to assist teachers in
creating new digital courses. In this field, they assume the role of prompters to assist teachers in finding
and selecting proper learning materials available on the internet.
      </p>
      <p>Currently, to facilitate the creation of a course, teachers can use authoring tools such as Absorb2,
Learnopoly3 or Elucidat4. These tools help teachers develop, launch and review an e-learning course,
but they cannot support them throughout creating a new digital course. Our idea is to give a chatbot the
task of finding existing Learning Objects (LOs) [15-17]. Through the chatbot suggestions, teachers can
use these reusable and interoperable LOs as building blocks for producing a course more quickly and
efficiently. Once discovered the LOs, teachers need to find a strategy for combining and sequencing
them to ensure that learning resources can be appropriately assembled in a course that can meet the
teachers' objectives and requirements.</p>
      <p>At the beginning of the interaction, the chatbot requests information related to the course to be
created. This information regards its difficulty, the number and duration of the lessons, the language,
and the course topics. (Figure 1).</p>
      <p>Regarding topics, skills and competencies, the chatbot allows adding items to the corresponding list
if the user needs it. Once the teacher has entered the course information, the parsing system checks the
orthographic and performs the translation into English (since the dataset is in English) via the
DeepTranslator library5.</p>
      <p>Subsequently, using the topics, the difficulty, type and duration, the chatbot can suggest which
learning objects teachers can combine to create the new digital course. Figure 2 shows how a teacher
selected two LOs to specify the necessary resources. If a LO contains exercises, the teacher can set to
repeat the activity if the student fails to finish a LO in the desired time or according to an established
rating.
5 Deep translator. https://pypi.org/project/deep-translator/ - Last access: 2023-05-01.</p>
    </sec>
    <sec id="sec-4">
      <title>Conversational Agent for Active Ageing</title>
      <p>The conversational agent we designed takes the name of Charlie. Charlie, implemented using Google
DialogFlow6, acts as a medical advisor, friend and carer for autonomous seniors living alone.</p>
      <p>To simplify interaction, Charlie provides limited choices that are easily understood and accessible
via the mobile phone or tablet screen. The dialogues are generally of short duration to avoid tiring the
user. Key features depicted in Figure 3 include the possibility of giving daily automatic notifications,
healthy recommendations and offering activity reminders about important events, such as the need to
take medicine. Charlie can also present news, weather forecast, or different forms of entertainment,
including a memory-based game and quizzes. Another feature includes active listening to help older
people improve their mood. The users indicate their thoughts, and then the assistant asks for information
regarding their emotional situation. Through telling a story, Charlie establishes a pretext to
communicate with the user and ask for information to develop a conversation. This functionality allows
the users to consider Charlie in a friendly way, pushing them to confide and express themselves without
worrying about communicating with artificial intelligence.</p>
      <p>Moreover, another agent's goal is to monitor the indexes of active life specifically defined to keep
the trend of older adults' physical-cognitive state under control. To this aim, we need to involve older
person's caregivers or relatives to configure the digital agent. As explained in the following Sections,
the idea is to help them compose monitoring rules that can define the active life indexes to be controlled.</p>
    </sec>
    <sec id="sec-5">
      <title>3. A Strategy for Training Chatbots 3.3.</title>
    </sec>
    <sec id="sec-6">
      <title>Training Agent in Education Domain</title>
      <p>Reusing learning objects (LOs) rather than their reinvention aims to save time and effort [18].
Moreover, from a quality point of view, the more a resource is reused, the more likely it is to be of high
quality simply because more people will have been exposed to it and have had the opportunity to
provide feedback [19]. To this aim, we need to involve domain experts who can use their experience of
solving problems in the past to build on and create new solutions in new situations.</p>
      <p>Most current e-learning platforms are closed systems that hardly share and reuse materials because
they are made in proprietary formats. To solve the problems of sharing and reusing teaching materials
in other e-learning systems, many international organisations established e-learning standards. The
Sharable Content Object Reference Model (SCOR [20]) is recognised as the most popular one, and the
IEEE-Standards Association has approved its Learning Object Metadata (LOM) [21]. Another standard,
the Dublin Core7, emerged over the years to facilitate the sharing and reuse of learning materials which
establishes metadata policies and provides suggestions for using the LOs.</p>
      <p>All these standard protocols allow teaching materials for different learning management systems to
be shared, reused, and integrated, but none agree on which metadata could be used for describing LOs.
Some studies [22] recommend a minimal metadata set representing an LO. However, even if no specific
rules are indicated, surveys in [23, 24] have shown that Dublin Core is suitable for describing the
bibliographic side of digital resources, and LOM allows the best representation of the pedagogical
aspects.</p>
      <p>Due to its nature, we decided to use LOM for our project, but a problem remains. How to exploit
this metadata to suggest proper LOs and combine them in a final course. According to works proposed
in [25-27], our idea is to use specific machine-learning (ML) techniques to analyse a wiki page
associated with each LO. Expert teachers are involved in creating these wiki pages to describe the
content covered by the LO and, in particular, its requirements and final competencies [28]. Then, the
model extracts metadata from the wiki pages and defines a sequence of LOs according to their
prerequisites. Figure 4 depicts a LO related to using Scratch, a block-based visual programming
language aimed at learning coding basics for students ages 8 to 16.</p>
      <p>The model we defined aims at parsing the wiki pages to extract relevant concepts that describe the
semantics of the linked LO. Using the LOM metadata, we can associate 72 features to each LO and 9
descriptive areas for categorising the information content in the teaching resource. The final goal is to
learn if a LO "A" is a prerequisite for a LO "B".</p>
      <p>To this aim, we need to create a "prerequisite" attribute by using a set of metadata such as (1) the
age of acquisition of a concept, (2) the age of acquisition of correlated concepts, (3) the length of a
concept description, (4) the number of mathematic expressions presented on each wiki page, and (5)
the frequency of concept visualisations. With the Age of Acquisition (AoA) of a concept, we refer to
the work presented in [29]. The study collects AoA ratings for 1,957 Italian content words (adjectives,
nouns, and verbs), asking participants to estimate the age at which they thought they had learned the
word as a result of a Web survey procedure. With AoA of correlated concepts, we mean the AoA
average value of the concepts that appear on the wiki page that describes a given concept. This second
type of feature aims to model the relationship between pairs of concepts. In particular, it evaluates if a
concept appears as a sub-string in the title or the description of the other concept.</p>
      <p>Then, we applied our model to a dataset of resources used to teach computer programming skills
and computational thinking. The dataset contains 554 LOs, and we asked to 11 students of the
Department of Computer Science at the University of Milano to find or write a wiki page for each of
these LOs to describe them. Then we enrolled 15 teachers recruited by the Social Thingum company8
to create new digital courses to test the effectiveness and efficiency of the suggestions provided by the
chatbot. In detail, our chatbot suggests which LOs to take into account by analysing the information
provided by the teacher about the topics, the difficulty, type and duration of the course to create. Then,
using Sentence-BERT (S-BERT)[30], a machine-learning model based on Transformers, the chatbot
computes the semantic similarity between input data and LO metadata. After discovering the better
LOs, the chatbot used the "prerequisite" attribute to suggest how to combine them for creating a course
according to the teacher's needs.</p>
      <p>Due to the limited number of records, in analysing the reliability and accuracy of our model, we
achieved only an average F1 of 0.68 over the test set. Nevertheless, we are confident this result could
be a good indication of the extraction model of the prerequisites that can be used for suggesting a
sequence of proper LOS to consider for creating a course.
3.4.</p>
    </sec>
    <sec id="sec-7">
      <title>Training Agent in Healthcare Domain</title>
      <p>As said before, we designed a chatbot in the healthcare domain to help caregivers and relatives to
monitor a set of indexes that describe the active life of their dear ones. To identify these indexes, domain
experts need to determine what to monitor for taking under control the trend of older people's
physicalcognitive state. To this aim, we focused on how to write rules that caregivers can establish depending
on data gathered by Charlie.</p>
      <p>Unfortunately, the problem with this strategy is that the caregivers are often "lost in the data sea"
and do not know which parameters to check for monitoring the senior's behaviour. To help caregivers,
we designed a model recommending which rules to adopt. Essentially, the idea is to develop
functionality to compute predictions and the consequent rules by extracting knowledge from the data
representing older adults' behaviours.</p>
      <p>In particular, we are investigating an approach that produces a set of readable and understandable
IF-THEN rules [31], which are easily interpretable. The rules are suggested by using BERT for
generating embedding representations helpful in capturing the semantic similarity between the elderly's
profile and a set of metadata describing the activities to monitor. The elderly profile is established using
a specific screening model we defined integrating the MoCA - Montreal Cognitive Assessment9 model,
the MMSE - Mini-Metal State Examination test [32] and the GPCog - General Practitioner Assessment
of Cognition10 provided by experts of the ASST (Aziende Socio Sanitarie Territoriali - Territorial
SocioHealth Companies) of Crema (Italy).</p>
      <p>Screening requires the caregiver to carry out a brief cognitive questionnaire on the patient,
administering quick tests to investigate the main cognitive functions (attention, memory, language,
perception, executive functions) and identify signs of possible deterioration. This neuropsychological
evaluation makes it possible to define a set of metadata to be associated with the older person. Then,
for each activity that the caregiver can indicate for the assisted person (news to provide, notifications,
reminders, quizzes, games, active listening or storytelling activities), the doctors of the ASST involved
in our project specified a description, objectives, possible benefits to do it, requirements, and
motivations by using a wiki page. According to the elderly's profiles and activity descriptions, our
model provides caregivers with a recommendation service that suggests how they can create the rules.
In detail, the model analyses the wiki page associated with each activity and then extracts from it
information that can better fit the older adult's profile.</p>
      <p>At the moment, we are in the preliminary phases of this work, so we do not have results helpful for
evaluating the reliability and accuracy of our model. Currently, we are training the model and
populating the dataset of activity wiki pages involving doctors of the ASST of Crema.</p>
    </sec>
    <sec id="sec-8">
      <title>4. Conclusion</title>
      <p>In this paper, we have presented two chatbots specifically designed to investigate how to involve
domain experts in the training process of the recommendation facility that the chatbot can use to help
users in complex decision-making tasks.</p>
      <p>The idea is to use intelligent assistants to help teachers create new courses or caregivers define rules
for monitoring older people's indexes of active life. To enable the chatbots to suggest correctly, they need
to be trained with the help of domain experts. These experts are not technical people but know the use
domains and have the competence to train the chatbots to provide helpful suggestions.</p>
      <p>Our EUD approach is based on asking domain experts to find or write wiki pages to describe the
learning objects or activities to use for monitoring older people's behaviours. Then, the model we
defined extracts from the wiki pages the metadata the chatbot uses to filter the learning objects or the
monitoring rules to adopt.</p>
      <p>For suggesting them, we decided to use Sentence-BERT, a machine-learning model based on
Transformers. BERT discovers the semantic similarity between the wiki page's metadata and the
properties the teachers used to specify the new course to create or the properties characterising older
people's profiles.</p>
      <p>At the moment, we carried out only a few preliminary tests, with results that attest to reasonable
indications of the extraction model. These tests mainly concern the strategies used to involve domain
experts in training the recommendation facility of a chatbot in the educational field. Nevertheless, we
are aware of some limitations that affect our study. The main issue concerns the sample size of
participants in our preliminary tests. Recruiting a few users does not allow us to present a complete
statistical confirmation and validation of the reliability of the collected data. For this reason, further
research aims to extend the study by involving more users with a broader context of use in each area of
interest where chatbots can be used.
[14] Chaves, A. P., &amp; Gerosa, M. A. (2020). How Should My Chatbot Interact? A Survey on Social
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