United Kingdom

In robotics, it is often not possible to learn useful policies using pure model-free reinforcement learning without significant reward shaping or  curriculum learning. As a consequence, many researchers rely on expert demonstrations to guide learning. However, acquiring expert  demonstrations can be expensive. This paper proposes an alternative approach where the solutions of previously solved tasks are used to produce an action prior that can facilitate exploration in future tasks. The action prior is a probability distribution over actions that summarizes the set of policies found solving previous tasks. Our results indicate that this approach can be used to solve robotic manipulation problems that would otherwise be infeasible without expert demonstrations. Source code is available at https://github.com/ondrejba/action_priors.

AAMAS 2021

Action Priors for Large Action Spaces in Robotics

**31st IEEE International Conference on Robot & Human Interactive Communication**
 This conference is a leading forum where state-of-the-art innovative results, the latest developments as well as future perspectives relating to robot and human interactive communication are presented and discussed.
 
 The conference covers a wide range of topics related to Robot and Human Interactive Communication, involving theories, methodologies, technologies, empirical and experimental studies. Papers related to the study of robotic technology, psychology, cognitive science, artificial intelligence, human factors, ethics and policies, interaction-based robot design and other topics related to human-robot interaction are welcome.
 
 **CONFERENCE THEME:**
 Social, asocial, and antisocial robots
 
 Robots are starting to populate our lives: at work, in our homes, hotels, shops. However, not everybody is comfortable with robots finding a place in society. For example, people may be afraid that robots will replace humans in their jobs. This belief is exacerbated by the media that, on one side, raise expectations of robots’ capabilities, while amplifying fears and worries on the other side.
 
 In the next years, due to the increasing request for interaction with people in social environments, academic research and market analyses predict that robots will become more and more “social”. But, at the same time, robots may incur the risk of being perceived as “asocial” as their pervasiveness in everyday environments may become an obstacle to social interaction between humans. Or they may even be rejected as “antisocial” if researchers do not take care to develop robots that behave according to the customs and habits of the communities where they are expected to operate.
 
 To prevent this from happening, robotic researchers can no longer take the luxury of being mere technicians. They must be capable of addressing all the challenges raised by future robot-populated communities in a multidisciplinary way. They need to share their knowledge with the public to make people aware of what robots really are, what expectations we can have from them, the risks we may incur, and the possible mitigation plans.
 
 While being open to any kind of contribution related to Human-Robot Interactive Communication, the RO-MAN 2022 conference will emphasize these aspects of robotic research. How can we create robots capable of being welcomed as our assistants and companions in society while, at the same time, not being perceived as “asocial” or “antisocial?” How can we create robots perceived as facilitators of the natural development of human beings and communities, rather than obstacles?
 
 Contributions from different disciplines, not exclusively related to technological development, will be welcomed as crucial to pave the way to global acceptance of future robots with an informed attitude.
 
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IEEE RO-MAN 2022

31st IEEE International Conference on Robot & Human Interactive Communication
This conference is a leading forum where state-of-the-art innovative results, the latest developments as well as future perspectives relating to robot and human interactive communication are presented and discussed.

technical paper

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Promoting Fair Proposers, Fair Responders or Both? Cost-Efficient Interference in the Spatial Ultimatum Game

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Multi-agent influence diagrams (MAIDs) are a popular form of graphical model that, for certain classes of games, have been shown to offer key complexity and explainability advantages over traditional extensive form game (EFG) representations. In this paper, we extend previous work on MAIDs by introducing the concept of a MAID subgame, as well as subgame perfect and trembling hand perfect equilibrium refinements. We then prove several equivalence results between MAIDs and EFGs. Finally, we describe an open source implementation for reasoning about MAIDs and computing their equilibria.

Equilibrium Refinements for Multi-Agent Influence Diagrams: Theory and Practice

This paper presents new algorithms and theoretical results for solutions to Multi-action Multi-armed Restless Bandits, an important but insufficiently studied generalization of traditional Multi-armed Restless Bandits (MARBs). Though MARBs are popular for modeling many problems, they are restricted to binary actions, i.e., "to act or not to act". This renders them unable to capture critical complexities faced by planners in real domains, such as a system manager balancing maintenance, repair, and job scheduling, or a health worker deciding among treatments for a given patient. Limited previous work on Multi-action MARBs has only been specialized to sub-problems. Here we derive multiple algorithms for use on general Multi-action MARBs using Lagrangian relaxation techniques, leading to the following contributions: (i) We develop BLam, a bound optimization algorithm which leverages problem convexity to quickly and provably converge to the well-performing Lagrange policy; (ii) We develop SampleLam, a fast sampling technique for estimating the Lagrange policy, and derive a concentration bound to investigate its convergence properties; (iii) We derive best and worst case computational complexities for our algorithms as well as our main competitor; (iv) We provide experimental results comparing our algorithms to baselines on simulated distributions, including one motivated by a real-world community health intervention task. Our approach achieves significant, up to ten-fold speedups over more general methods without sacrificing performance and is widely applicable across general Multi-action MARBs. Code is available at https://github.com/killian-34/MAMARB-Lagrange-Policies.

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Action Priors for Large Action Spaces in Robotics

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Promoting Fair Proposers, Fair Responders or Both? Cost-Efficient Interference in the Spatial Ultimatum Game

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Action Priors for Large Action Spaces in Robotics

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Promoting Fair Proposers, Fair Responders or Both? Cost-Efficient Interference in the Spatial Ultimatum Game

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Expectations about mental states of a robot influence performance in a collaborative task with a robot for males but not females

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PRESENTATIONS

CONFERENCES

COMPANY

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