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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Eindhoven, The Netherlands
*Corresponding author
daniele.pretolesi@ait.ac.at (D. Pretolesi)</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Persuasive XR Training: Improving Training with AI and Dashboards</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Daniele Pretolesi</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Olivia Zechner</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>AIT - Austrian Institute of Technology</institution>
          ,
          <addr-line>Vienna</addr-line>
          ,
          <country country="AT">Austria</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>000</volume>
      <fpage>0</fpage>
      <lpage>0001</lpage>
      <abstract>
        <p>With the rapid growth of Extended Reality (XR) technologies for training purposes, it has become essential to incorporate Artificial Intelligence (AI) modules into the simulations to assist trainers and trainees. One powerful AI solution is the use of recommender systems (RS) to enhance user interactions and experiences in immersive training. This work explores the integration of a RS into an XR training platform and focuses on the design of persuasive interfaces to present recommendations. Personalised training goals can be achieved for more successful outcomes by allowing trainers to modify training scenarios during the exercise. The goal of this work is to illustrate how effective integration of AI and persuasive interfaces in XR training platforms can result in successful and personalised training outcomes.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Persuasive interface</kwd>
        <kwd>XR Training</kwd>
        <kwd>Persuasive technology</kwd>
        <kwd>Artificial Intelligence1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>The implementation of Extended Reality (XR) training systems has gained significant attention
in various domains, including but not limited to law enforcement, medical first responders, and
CBRNe specialists [22,25,27]. These systems offer a highly customisable and realistic
simulation of complex environments, providing trainers and trainees with a valuable tool to
prepare for real-world scenarios. Training within these domains often includes simulation of
high-risk and high-stress environments, not permitted or too challenging to replicate in a
realworld training setting. The inclusion of vulnerable populations (e.g., infants, people with
disabilities) or hazardous equipment (e.g., explosives or poisonous substances) would be an
example. VR training offers the opportunity to increase scenario repetitions with increasing
levels of difficulty necessary to produce optimal training outputs. Stress levels of scenarios can
be increased by including additional stressors in a scenario (e.g. weapons, number of injured
avatars, loud noise). For a successful simulation training the right level of stress exposure plays
a crucial role in optimising training outcomes [27].</p>
      <p>Despite the benefits of these systems, one of their limitations is the lack of adaptability
during a training session. For instance, consider a scenario where the virtual environment is
too stressful for the trainees, but it is not possible for the trainer to make changes to reduce the
stress level during the session. To ad- dress this issue, the integration of a recommendation
system (RS) and a control dashboard can be particularly advantageous. The dashboard serves
as a bridge between the AI and the trainer, allowing for real-time presentation of automatic
recommendations adapted to the conditions of the participants. This enhances the
personalisation of the training experience, by promoting engagement and positive learning
outcomes.</p>
      <p>The aim of this work is to present how successful and personalised training outcomes can be
achieved through the effective integration of AI and persuasive interfaces in XR training
platforms.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Works</title>
      <p>
        The use of RSs has become ubiquitous in websites and applications as a means to enhance
the user experience through the provision of personalised recommendations based on the
user’s interaction history with the system. The primary objective of RSs is to advertise products
or services that are likely to be of interest to the user. In the field of RSs, research efforts have
mainly been directed towards the computational aspects, with a focus on improving the
efficacy and relevancy of the recommendations. This has led to the development of various AI
techniques, including deep and geometric learning [
        <xref ref-type="bibr" rid="ref14">14, 29</xref>
        ] and Bayesian and collaborative
filtering methods [
        <xref ref-type="bibr" rid="ref7">7, 24</xref>
        ]. However, despite the significant progress made in improving the
computational aspects of RSs [28], little attention has been paid to enhancing the way users
interact with these systems. In recent years, there has been a growing interest in the
presentation level of RSs [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], with a focus on understanding the impact of these systems on
persuasion and satisfaction [17]. As the quality of recommendations increases, it becomes
increasingly important to provide users with transparent and interpretable visualizations that
support their understanding and interaction with the RS [23]. With the rapid advancement and
widespread adoption of virtual and augmented reality, there has been a growing interest in
exploring the integration of RSs into these technologies. However, these works have largely
focused on the computational aspects of the recommendation, neglecting the important
elements of presentation and explainability [
        <xref ref-type="bibr" rid="ref11 ref8">8, 11, 26</xref>
        ].
      </p>
      <p>
        In the context of XR training, research has been conducted to provide trainers with
dashboards to review a training session with the possibility to playback the actions, flag
relevant events and control trainees’ stress levels [
        <xref ref-type="bibr" rid="ref13 ref16">13, 16, 19</xref>
        ]. Albeit successful, these solutions
only provide trainers with an overview of what is currently happening in the virtual
environment without the possibility of making changes to the scene, such as introducing an
additional stressor, if necessary.
      </p>
      <p>Following the direction set in [20], which presented a framework for implementing
AIbased RS in the context of XR training, this work will discuss how persuasive interfaces (i.e.
dashboards) and AI methods might improve the effectiveness of XR training systems. The next
sections will introduce the proposed solution and present the design for a persuasive
dashboard. Further, the explain- ability and persuasive elements of the suggested AI will be
discussed.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Envisioned Solution</title>
      <sec id="sec-3-1">
        <title>3.1. AI-Supported Training</title>
        <p>In order to address the challenges of creating adaptive training scenarios, a novel strategy
is proposed. A machine learning approach is implemented to provide meaningful
recommendations for elements such as stressors, weather conditions, and NPCs that can be
used to enhance the training experience and customise the level of difficulty trainees face. The
data collected during previous training sessions are used to tailor each scenario to the trainees’
needs. In the current version stress level measurement data is based on heart rate (HR), heart
rate variability (HRV) and electrodermal activity (EDA). The proposed solution (Figure 1)
leverages data from both the trainer and the trainees to enhance the effective- ness of the
training. By allowing trainers to modify specific stressors during the exercise, the system can
provide personalised training experiences that better meet the needs of the participants.</p>
        <p>The envisioned system for generating recommendations relies on a combination of
supervised and unsupervised learning techniques, as well as reinforcement learning.
Supervised learning would be used to train the system on existing data, while unsupervised
learning would be used to identify patterns and trends in the data that may not be immediately
obvious. The system would also use reinforcement learning techniques to optimise the training
scenarios and ensure that they provide the best possible experience for the trainees. The
insights gained from supervised and unsupervised learning, along with the optimisation
provided by reinforcement learning, would be used to generate personalised XR training
recommendations based on various factors, such as response to stressors, behaviour during
training, and feedback. Once the model has generated recommendations, it would use
persuasive techniques to encourage trainers to follow these recommendations. 2</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Envisioned Solution</title>
        <p>
          The user interface for the persuasive RS plays a critical role in helping trainers make informed
decisions for their trainees. The interface utilises data analysis and machine learning
algorithms to offer customised recommendations. Additionally, it employs persuasive
strategies to motivate trainers to implement these recommendations. Trainers were consulted
within the Med1stMR project [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]1 to identify the essential features required in a training
dashboard for an XR system
developed to train medical first responders in handling mass casualty incidents. Table 1
outlines the requirements identified by trainers, including the need for real-time feedback, and
the ability to modify stressors and other elements of the training scenario. Based on these
requirements, our solution was built with a focus on providing a user-friendly dashboard that
allows trainers to easily access and analyse data from previous training sessions, as well as
receive personalised recommendations for enhancing the training experience.
1 The project is funded by the European Union’s Horizon 2020 Research and Innova- tion Program under grant
agreement No 101021775
        </p>
        <sec id="sec-3-2-1">
          <title>View of the status of the trainee: stress measurement</title>
        </sec>
        <sec id="sec-3-2-2">
          <title>Weather conditions</title>
        </sec>
        <sec id="sec-3-2-3">
          <title>Time of day/night</title>
        </sec>
        <sec id="sec-3-2-4">
          <title>Additional casualties</title>
        </sec>
        <sec id="sec-3-2-5">
          <title>Inclusion of stressors</title>
        </sec>
        <sec id="sec-3-2-6">
          <title>The trainer should be informed about upcoming scheduled events. Trainer has final say about changes</title>
        </sec>
        <sec id="sec-3-2-7">
          <title>Ensure trainee’s safety</title>
        </sec>
        <sec id="sec-3-2-8">
          <title>Modify training scenario to prevent redundancy in training</title>
        </sec>
        <sec id="sec-3-2-9">
          <title>Adjust training scenarios</title>
          <p>based on trainee performance</p>
        </sec>
        <sec id="sec-3-2-10">
          <title>Trainer keeps final control over the scenario</title>
          <p>
            The interface is designed with persuasive strategies in mind [18], as the goal is to influence
trainers to make decisions that are most beneficial for their trainees. One persuasive strategy
used in the interface is the principle of social proof [
            <xref ref-type="bibr" rid="ref3">3</xref>
            ], which involves showing trainers
evidence of the effectiveness of certain training scenarios or stressors based on past data. This
can help to convince trainers to adopt these recommendations and use them in their training
sessions. Another persuasive strategy used in the interface is the principle of authority [
            <xref ref-type="bibr" rid="ref3">3</xref>
            ],
which involves using the system’s knowledge and experience, based on previous training
sessions and feedback from past training, to influence the decisions of trainers. For example,
the system could use natural language processing to provide real- time feedback during
training sessions, offering guidance and advice based on the performance of the trainees. This
could help to establish the system as an expert in the field of training and encourage trainers
to follow its recommendations. Figure 2, presents an initial prototype of the proposed interface
which includes the above-mentioned features.
          </p>
          <p>
            By leveraging data analysis, machine learning, natural language processing, and persuasive
techniques, the system can help trainers to make the best deci- sions for their trainees,
leading to more effective training outcomes and improved performance. Finding the optimal
stress level to maximize learning performance is a challenge in simulation training [
            <xref ref-type="bibr" rid="ref10">10</xref>
            ] and
can be different for each individual. It is therefore currently strongly recommended to keep
the trainer in the loop (human-in-the-loop) so they can review and validate the
recommendation made by the system. Keeping the trainer involved may have the additional
benefit to build a relationship between the RS and the trainer, increasing the trust in the
technology.
          </p>
        </sec>
      </sec>
      <sec id="sec-3-3">
        <title>3.3. Explainability</title>
        <p>
          The efficacy of the presented dashboard relies on the ability of the trainer to understand and
follow the suggestions provided by the AI model. To ensure a dependable relationship between
the model and the user, the works of [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ], [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ] and [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] were used to implement explainable design
solutions in the dashboard. For instance, in the top right corner of Figure 2, the AI explains to
the trainer that the stress level is currently below the optimal level and that worsening the
victim’s condition could resolve the issue. Similarly, in the bottom right corner of Figure 2, the
model presents elements included in previous training that could increase the stress of the
trainees by showing the expected increase in stress level.
        </p>
      </sec>
      <sec id="sec-3-4">
        <title>3.4. Evaluation</title>
        <p>Evaluation studies will be performed to assess the design and effectiveness of the proposed
dashboard. In particular, the evaluation will focus on examining the quality of the presented
recommendations, the design of the persuasive interface, and the user experience of the
trainers.</p>
        <p>To assess the quality of the recommended items, the ResQue framework [21] will be used.
This user-centered framework allows for easy identification of areas of improvement in the
recommendation system as well as in the interface and user interaction modalities. The
evaluation will measure the effectiveness of the proposed persuasive strategies in motivating
trainers to adopt effective teaching practices.</p>
        <p>
          To evaluate the design of the persuasive interface, an adapted version of the Technology
Acceptance Model (TAM) questionnaire [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] will be used. This adaptation of the TAM, developed
in [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ], has been shown to be effective in measuring user acceptance in persuasive interfaces
[
          <xref ref-type="bibr" rid="ref15">15</xref>
          ]. The questionnaire will assess factors such as perceived ease of use, usefulness, and
attitude towards the dashboard, providing insight into the effectiveness of the persuasive
strategies employed in the interface design.
        </p>
        <p>Overall, the evaluation studies will provide valuable feedback on the effectiveness of the
proposed dashboard and persuasive strategies, as well as identify areas for further
improvement to enhance the learning outcomes of trainees in XR training programs.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusion</title>
      <p>This work demonstrates how the integration of AI and persuasive interface design may
enhance the performance of trainers in XR training systems. By utilising AI algorithms to
analyse data collected from trainers and trainees, the system can provide real-time feedback
to trainers regarding their teaching strategies and effectiveness. Moreover, by incorporating
persuasive design principles, such as authority and social influence, the system can motivate
trainers to increase their engagement with the training process. By presenting data and
insights in a clear and compelling manner, the system can encourage trainers to adopt effective
teaching practices and improve the quality of their training. Overall, this approach has the
potential to improve the quality and acceptance of XR training systems and contribute to the
overall success of the training exercise.</p>
      <p>In conclusion, future work will aim to improve the persuasive design of the trainer’s
dashboard through user evaluations conducted in both laboratory and real-world settings. In
addition to the proposed persuasive strategies of authority and social proof, the dashboard
should also incorporate other approaches such as gamification and the persuasive strategy of
commitment and consistency.
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