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    <article-meta>
      <title-group>
        <article-title>Autonomy in Human-AI Cooperation</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Vildan Salikutluk</string-name>
          <email>vildan.salikutluk@tu-darmstadt.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
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        </contrib>
        <contrib contrib-type="author">
          <string-name>Eric Frodl</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Franziska Herbert</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dirk Balfanz</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
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        </contrib>
        <contrib contrib-type="author">
          <string-name>Dorothea Koert</string-name>
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          <xref ref-type="aff" rid="aff2">2</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
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        </contrib>
        <contrib contrib-type="editor">
          <string-name>Human-AI Cooperation, Interactive Human-AI Teaming, Adaptive Autonomy, Collaborative Problem-Solving, Robotic Task</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Centre for Cognitive Science, Technical University Darmstadt</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Interactive AI Algorithms &amp; Cognitive Models for Human-AI Interaction, Computer Science Department, Technical University Darmstadt</institution>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Models of Higher Cognition, Human Sciences Department, Technical University Darmstadt</institution>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Workshop Proce dings</institution>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>ing Automation Experiences</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>Human-AI teams have the potential to produce improved outcomes in various tasks as opposed to each team member working alone. However, there are various factors that influence human-AI team performance which potentially difer from classical Human-Computer Interaction settings. Specifically, there is existing work indicating that it is beneficial for AI systems to automatically adapt their autonomy within the team and task in order to work towards achieving a shared goal more efectively. Thus, in this paper, we describe a concept of situational adaptive autonomy for human-AI cooperation in a shared workspace setting. We discuss that task complexity and models for the AI system's understanding of their human teammate, i.e. Theory of Mind models (ToMMs) might be helpful to implement situational adaptation of AI autonomy such that interaction and team performance can be improved. We present an experimental setup for a cooperative real-world robotic task and a corresponding approximation in a grid-world in which we plan to investigate situational adaptive autonomy within a shared workspace in an interactive human-AI team.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Recent artificial intelligence (AI) systems and robots
port humans at work [1, 2, 3] or in everyday life tasks
[4, 2, 5, 6, 7, 8]. However, improving task outcomes
through human-AI collaboration is not trivial, often
casespecific, and depends on the abilities and characteristics
of each party [9]. While general design principles for
classical human-computer interaction (HCI) have already
been explored well, there is a need to update them for
designing interactions with AI systems [10, 11, 12] such
that human-AI teams can solve problems synergistically
and improve their performance together. Hereby, it is
important to consider factors where current and future
AI systems might difer from classical HCI systems.
omy that AI systems can possibly achieve during
cooperative tasks [13]. When humans interact with technical
systems as tools, they commonly automate a very specific
sub-task to achieve their overall goals more eficiently
by using the system [14, 15, 16]. In such cases, systems
have a specific and limited purpose but in general no
autonomy within the task and the team. On the other
end of the autonomy spectrum lies a fully autonomous
collaboration partner with whom the human outputs a
This work was funded by German Federal Ministry of Education
and Research (project IKIDA, 01IS20045).
nEvelop-O
collective result for a shared goal, i.e. human-human
interaction, e.g. when colleagues collaborate with each
other. Such collaboration depends on communication,
interaction with AI agents falls somewhere in between
the ends of the spectrum shown in Fig. 1.</p>
      <p>Diferent concepts for autonomy levels have also been
proposed in previous work [19, 13, 20, 21]. However,
high(er) autonomy in systems does not necessarily
increase team performance or is preferred by their human
counterparts in every situation [22]. Previous work also
indicated that the ability to slide along the autonomy
scale and dynamically adapt autonomy levels is
beneifcial [ 23, 21, 13, 24]. In more recent work, autonomy
is often specified as a set of autonomy levels which an
operator can switch (manually) [19, 20, 21].
Automatresults in specific use cases, e.g. multi-agent systems
without human interaction [23], Unmanned Aerial
Vehicle path-planning [21], settings where an operator
remotely controls a robot in hazardous environments [13]
or simulation-based evaluations for a cleaning and an
inventory scenario with a mobile manipulator [24].
However, we see a lack of experimental real-world evaluations
of concepts for situational adaptation of AI autonomy in
cooperative shared workspace settings.</p>
      <sec id="sec-1-1">
        <title>Therefore, with our planned experiments we aim to adaptation of autonomy in shared workspaces that facilitate improved team performance and interaction within the human-AI team. In particular, we suggest to incorpo</title>
        <p>One distinguishing factor is the higher degree of auton- ically adjusting autonomy already showed promising
© 2023 Copyright for this paper by its authors. Use permitted under Creative Commons License rate measures for task complexity as well as models for
the AI system’s understanding of their human teammate,
i.e. Theory of Mind models [25, 26, 27], to automatically where a human operator remotely controls one or
multidecide when the AI system should switch its autonomy ple robots in hazardous or space environments [34, 34]
level in collaborative interaction with their human part- and for path planning of Unmanned Aerial Vehicles [21].
ner. This should ensure that interaction is initiated and In particular, [21] shows that human-AI cooperation with
expressed by the AI system only when it is appropriate autonomy adaptation can lead to better performance as
and helpful for the human and the overall task goal. The opposed to either human or system completing the task
proposed concept for situational adaptive autonomy re- alone.
sults in an interactive AI system which can slide on the Generally, there is some evidence that humans profit
autonomy spectrum shown in Fig. 1 in blue. from [35] and are in favor of systems having a high(er)</p>
        <p>We advocate for investigating interaction paradigms level of autonomy [13] when it helps their goals. Humans
arising when interactive AI systems slide along this au- also share their task load more when they perceive a
systonomy scale. To this end, we propose an experimen- tem’s behavior as human-like [36]. Nevertheless, there
tal task setup within a grid-world environment and a is also literature about how humans sometimes prefer
real-world robotic task to gain deeper insights into the when they have control over systems [37, 10] or reduce
interaction with a coordinating human-AI team. the systems’ autonomy [35]. Also, the interplay of a
system’s autonomy level and the situational awareness of
its user has been investigated [38]. Further work also
ac2. Background knowledges that the design and evaluation of human-AI
interaction (partly) depends on the autonomy spectrum
There is a large body of previous work defining au- on which systems can lay from just being tools to being
tonomy and its possible levels for AI or robotic agents counterparts or teammates [39].
[28, 22, 29, 30, 31, 32, 33]. For a more detailed overview Some research also demonstrates the potential of
adapon the definition of autonomy that aligns well with how tive autonomy in shared workspace settings [40, 24]. In
it is framed in our work we refer the interested reader to [40], the authors present a framework that incorporates
[31, 32]. In this section, we focus on the discussion of re- situation assessment and planning together with human
lated work that aims to enable AI agents to automatically intention prediction and reactive action execution. Their
adjust their level of autonomy (Section 2.1) and subse- approach enables a robot to adapt to user preferences
quently provide a short background on task complexity allowing the human partner to be more passive or
acand Theory of Mind models, which we propose as two tive in giving commands. A Theory of Mind model for
important factors to implement situational adjustment predicting temporary absence or inattention of the
huof autonomy in shared workspace settings (Section 2.2). man is proposed in [24] to automatically adapt robot
communication patterns during the execution of a
coop2.1. Adaptive Autonomy erative table cleaning task. However, both approaches are
only evaluated in virtual environments with simulated
humans. We found a lack of evaluations for adjustable
autonomy in shared workspaces with real human users
and in real-world robotic scenarios.</p>
      </sec>
      <sec id="sec-1-2">
        <title>Dynamic adjustment of autonomy has been explored a lot in settings where multiple AI agents collaborated [23]. Additionally, automatic adjustment of an AI agent’s autonomy has been shown to be beneficial in settings</title>
        <sec id="sec-1-2-1">
          <title>2.2. Task Complexity &amp; Theory of Mind 3.1. Initiative and Delegation within the Human-AI Team</title>
          <p>There are various existing definitions for task complexity
[41, 42, 43, 44]. The definitions often aim to describe how For our approach and all planned experiments, there is
much cognitive processing capabilities, skills, informa- no debating or adjusting of the goal itself, i.e. the human
tion, and knowledge availability are necessary to perform sets the overall task goal, which is to be achieved with
a task [45, 41]. Furthermore, objective task complexity the help of the AI teammate [19] and the goal is known
can comprise of number of task components, goals, or to both. In order to investigate efects on the
interacpossible solution paths [46, 47]. Overall, [48] consolidate tion paradigms for situational adaptive autonomy in a
existing definitions into one model for task complexity. shared workspace, we first of all require a concrete
impleIt comprises of ten dimensions, e.g. the number of task mentation of autonomy levels for the AI agent. Existing
components, their interdependency and time-related con- concepts for autonomy levels [22, 38, 59, 60, 32, 28, 29]
straints. Furthermore, there are frameworks for task com- have often been proposed in a more theoretical
framplexity for human-system integration [49] and for human ing. All of these concepts include at least 10 levels of
teams [47]. Specifically, [ 47] distinguishes between com- autonomy for an AI agent.
ponent complexity which considers task aspects for the For our concrete implementation we decided to follow
individuals within the team and coordinative complexity the concept from [29, 28] but summarize their 10 levels
regarding factors of interaction and teamwork such as into four. This is due to two reasons: First, while [29, 28]
interdependencies and solution diversity. distinguish some levels by how and if the robot informs</p>
          <p>Task complexity influences individual and group per- the human about its choice, we implement the AI
sysformance in diferent tasks [ 48, 50]. While teams perform tem’s decision on how and when to notify or question
worse compared to individuals when working on lower the human based on a ToMM. This model considers the
complexity tasks, higher task complexity leads to interact- situation and current state of its human partner and thus
ing groups outperforming individual performance [50]. only informs or asks them about anything when it
asThis means, humans can profit from support when work- sumes that the human is able to comprehend and reply.
ing on tasks with higher task complexity. This is also Thus, we do not separate such communication with the
in line with [51] who found that humans rely more on human partner in distinct autonomy levels. Second, we
support of systems when there is higher task complex- hypothesize that it is easier for the human teammate
ity. While there are also other aspects which influence to understand in which autonomy level the AI partner
the performance of human-AI teams [52], they might currently is when there are less levels overall.
be most successful when humans and AI agents com- We implement the expression of the AI system’s
autonplement each other [53, 54]. Complementarity requires omy level by how much initiative it takes to deviate from
among other things that teammates have awareness of its currently assigned sub-task if it assumes a benefit for
the situation [55, 56] and about what their teammate the team performance. We specify the following four
knows and plans, which is known as Theory of Mind, diferent types of initiative.
i.e. the modeling of mental states of others [25]. They No Initiative: the AI just continues with its current
are also used computationally in various human-AI in- sub-task; makes no suggestions if it notices sub-tasks
teraction settings [26, 27, 24, 57, 58] such that they allow with higher priority; goes into idle mode if it encounters
for anticipation for human actions and planning with an a problem during its sub task execution.
appropriate model of the human in the interaction. This Low Initiative: If during a sub-task execution the AI
can ensure that systems can adjust for specific users and encounters a problem or notices a sub-task with a higher
plan better (together) with them [24]. priority, it presents a list of possible alternative sub-tasks
to the human and waits to see if they choose one.
3. Situational Adaptive Autonomy Moderate Initiative: If during a sub-task execution
the AI encounters a problem or notices a sub-task with a
for Cooperative Tasks in Shared higher priority it presents the option it assumes as the
Workspaces best possibility and waits for confirmation (or rejection).</p>
          <p>Full Initiative: If during a sub-task execution the AI
Situational adaptive autonomy may influence the interac- encounters a problem or notices a sub-task with a higher
tion and performance of human-AI teams in cooperative priority, the AI executes an alternative it considers the
tasks. In this section, we discuss how we plan to realize best possibility for improvement; if the ToMM indicates
a concept of situational adaptive autonomy in a shared human availability it informs the human and ask them if
workspace setting (Section 3.1) and describe the task in the decision was okay.
which we plan to evaluate our approach (Section 3.2). Overall, assigning sub-tasks can be based on access,
competence and permission to execute them as also
proposed in [31]. The AI system can lower its autonomy
when uncertainties or problems arise or if a miss match
between its own competence and (sub-)task requirements
occurs. Additionally, humans can intervene in the AI’s
actions or potentially delegate new sub-tasks. An
increase in autonomy can be beneficial, e.g. when only
execution of a sub-task with higher priority can prevent
catastrophic failure of the overall task and the ToMM
indicates current unavailability or missing situational
awareness of the human. We theorize that when task
complexity is low(er), autonomy and initiative can be
low(er) as well while the team could profit from high(er)
autonomy and initiative from the AI when task
complexity is high(er), as in [50].</p>
        </sec>
        <sec id="sec-1-2-2">
          <title>3.2. Experimental Task Setting</title>
          <p>We consider a setting in a shared workspace where the
overall task consists of sub-tasks that can be either
performed by only the AI agent, only the human or both
but in some cases with potentially diferent degree of
eficiency. Additionally, we assume that there is always
a set of sub-tasks that may result in or prevent failure
of the overall task goal. Our setups for the robotic task
and the corresponding abstracted grid-world, inspired by
[61], are illustrated in Fig. 2. In the proposed task, the
human and AI need to organize and process the contents of
boxes which get delivered over time. These boxes contain
various objects, such as books or documents that require
individual handling before they can be stored in their
designated spaces. Task performance can be measured
e.g. by the number of completely sorted boxes over a
predefined time. This task cannot only vary situationally
in its complexity but also requires ToMM for successful
collaboration.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>4. Implications and Future Work</title>
      <p>For the development of interaction paradigms and a more
common definition of situational autonomy adaptation in
shared workspace settings, we consider it crucial to gain
empirical insights from evaluations with real humans in
real robotic tasks. To this end, we plan to implement the
concept described in this paper and evaluate it with the
discussed task setting. We strive to gain a deeper
understanding of how factors such as task complexity or ToMM
can possibly be used for situational autonomy adaptation
in shared workspaces. Particularly, we consider it
important to investigate the efects of the resulting situational
autonomy adaptation on the performance of and
interaction within human-AI teams. We plan to test whether
our conceptualized and implemented autonomy levels
and corresponding initiative types positively impact team
performance in human-AI interaction for a collaborative
task within a shared workspace.</p>
      <p>
        Generally, we advocate that the successful deployment
of situational autonomy adaptation in human-AI
interaction requires more interdisciplinary exchange and
research to better understand the implications for both
humans and AI systems in the future.
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