Agents
Incentivized Exploration via Filtered Posterior Sampling
Kalvit, Anand, Slivkins, Aleksandrs, Gur, Yonatan
A principal(social planner) interacts sequentially with a flow of self-interested agents that each take actions, consume information, and produce information over time. The planner's goal is to maximize the aggregate utility of all agents it interacts with, which necessitates agents to occasionally take exploratory actions that might otherwise be deemed inferior from an empirical standpoint. While such exploratory actions are the cornerstone of online learning as they help the principal learn the best actions over time, they also represent misaligned incentives between the principal and individual agents. How can a welfare-maximizing principal achieve her goal in the presence of such misaligned incentives? This is the essence of the incentivized exploration problem.
An Autonomous Large Language Model Agent for Chemical Literature Data Mining
Chen, Kexin, Cao, Hanqun, Li, Junyou, Du, Yuyang, Guo, Menghao, Zeng, Xin, Li, Lanqing, Qiu, Jiezhong, Heng, Pheng Ann, Chen, Guangyong
Chemical synthesis, which is crucial for advancing material synthesis and drug discovery, impacts various sectors including environmental science and healthcare. The rise of technology in chemistry has generated extensive chemical data, challenging researchers to discern patterns and refine synthesis processes. Artificial intelligence (AI) helps by analyzing data to optimize synthesis and increase yields. However, AI faces challenges in processing literature data due to the unstructured format and diverse writing style of chemical literature. To overcome these difficulties, we introduce an end-to-end AI agent framework capable of high-fidelity extraction from extensive chemical literature. This AI agent employs large language models (LLMs) for prompt generation and iterative optimization. It functions as a chemistry assistant, automating data collection and analysis, thereby saving manpower and enhancing performance. Our framework's efficacy is evaluated using accuracy, recall, and F1 score of reaction condition data, and we compared our method with human experts in terms of content correctness and time efficiency. The proposed approach marks a significant advancement in automating chemical literature extraction and demonstrates the potential for AI to revolutionize data management and utilization in chemistry.
Order-Optimal Regret in Distributed Kernel Bandits using Uniform Sampling with Shared Randomness
Pavlovic, Nikola, Salgia, Sudeep, Zhao, Qing
We consider distributed kernel bandits where $N$ agents aim to collaboratively maximize an unknown reward function that lies in a reproducing kernel Hilbert space. Each agent sequentially queries the function to obtain noisy observations at the query points. Agents can share information through a central server, with the objective of minimizing regret that is accumulating over time $T$ and aggregating over agents. We develop the first algorithm that achieves the optimal regret order (as defined by centralized learning) with a communication cost that is sublinear in both $N$ and $T$. The key features of the proposed algorithm are the uniform exploration at the local agents and shared randomness with the central server. Working together with the sparse approximation of the GP model, these two key components make it possible to preserve the learning rate of the centralized setting at a diminishing rate of communication.
A Conflict-Aware Optimal Goal Assignment Algorithm for Multi-Robot Systems
The fundamental goal assignment problem for a multi-robot application aims to assign a unique goal to each robot while ensuring collision-free paths, minimizing the total movement cost. A plausible algorithmic solution to this NP-hard problem involves an iterative process that integrates a task planner to compute the goal assignment while ignoring the collision possibilities among the robots and a multi-agent path-finding algorithm to find the collision-free trajectories for a given assignment. This procedure involves a method for computing the next best assignment given the current best assignment. A naive way of computing the next best assignment, as done in the state-of-the-art solutions, becomes a roadblock to achieving scalability in solving the overall problem. To obviate this bottleneck, we propose an efficient conflict-guided method to compute the next best assignment. Additionally, we introduce two more optimizations to the algorithm -- first for avoiding the unconstrained path computations between robot-goal pairs wherever possible, and the second to prevent duplicate constrained path computations for multiple robot-goal pairs. We extensively evaluate our algorithm for up to a hundred robots on several benchmark workspaces. The results demonstrate that the proposed algorithm achieves nearly an order of magnitude speedup over the state-of-the-art algorithm, showcasing its efficacy in real-world scenarios.
Grounding from an AI and Cognitive Science Lens
Bajaj, Goonmeet, Parthasarathy, Srinivasan, Shalin, Valerie L., Sheth, Amit
Grounding is a challenging problem, requiring a formal definition and different levels of abstraction. This article explores grounding from both cognitive science and machine learning perspectives. It identifies the subtleties of grounding, its significance for collaborative agents, and similarities and differences in grounding approaches in both communities. The article examines the potential of neuro-symbolic approaches tailored for grounding tasks, showcasing how they can more comprehensively address grounding. Finally, we discuss areas for further exploration and development in grounding.
Feudal Networks for Visual Navigation
Johnson, Faith, Cao, Bryan Bo, Dana, Kristin, Jain, Shubham, Ashok, Ashwin
Visual navigation follows the intuition that humans can navigate without detailed maps. A common approach is interactive exploration while building a topological graph with images at nodes that can be used for planning. Recent variations learn from passive videos and can navigate using complex social and semantic cues. However, a significant number of training videos are needed, large graphs are utilized, and scenes are not unseen since odometry is utilized. We introduce a new approach to visual navigation using feudal learning, which employs a hierarchical structure consisting of a worker agent, a mid-level manager, and a high-level manager. Key to the feudal learning paradigm, agents at each level see a different aspect of the task and operate at different spatial and temporal scales. Two unique modules are developed in this framework. For the high-level manager, we learn a memory proxy map in a self supervised manner to record prior observations in a learned latent space and avoid the use of graphs and odometry. For the mid-level manager, we develop a waypoint network that outputs intermediate subgoals imitating human waypoint selection during local navigation. This waypoint network is pre-trained using a new, small set of teleoperation videos that we make publicly available, with training environments different from testing environments. The resulting feudal navigation network achieves near SOTA performance, while providing a novel no-RL, no-graph, no-odometry, no-metric map approach to the image goal navigation task.
Learning Progress Driven Multi-Agent Curriculum
Zhao, Wenshuai, Li, Zhiyuan, Pajarinen, Joni
Curriculum reinforcement learning (CRL) aims to speed up learning by gradually increasing the difficulty of a task, usually quantified by the achievable expected return. Inspired by the success of CRL in single-agent settings, a few works have attempted to apply CRL to multi-agent reinforcement learning (MARL) using the number of agents to control task difficulty. However, existing works typically use manually defined curricula such as a linear scheme. In this paper, we first apply state-of-the-art single-agent self-paced CRL to sparse reward MARL. Although with satisfying performance, we identify two potential flaws of the curriculum generated by existing reward-based CRL methods: (1) tasks with high returns may not provide informative learning signals and (2) the exacerbated credit assignment difficulty in tasks where more agents yield higher returns. Thereby, we further propose self-paced MARL (SPMARL) to prioritize tasks based on \textit{learning progress} instead of the episode return. Our method not only outperforms baselines in three challenging sparse-reward benchmarks but also converges faster than self-paced CRL.
On-Demand Sampling: Learning Optimally from Multiple Distributions ∗ Nika Haghtalab, Michael I. Jordan, and Eric Zhao University of California, Berkeley
Societal and real-world considerations such as robustness, fairness, social welfare and multi-agent tradeoffs have given rise to multi-distribution learning paradigms, such as collaborative [5], group distributionally robust [36], and fair federated learning [27]. In each of these settings, a learner seeks to minimize its worstcase loss over a set of n predefined distributions, while using as few samples as possible. In this paper, we establish the optimal sample complexity of these learning paradigms and give algorithms that meet this sample complexity.
A Background
A.1 Partially Observable Mackov Decision Process We follow previous works [25] to consider MARL as a partially observable Markov games [22]. We define a set of states S describing the possible configurations of all n agents. Then, each agent i gets rewards as a function of the state and agent's action r In the following paragraph, we use superscript to indicate agent's index and subscript to indicate time step for states, observations, rewards and actions. A.2 Decision Transformer Decision Transformer [3] using Transformer [44] which is an architecture to efficiently model sequential data shows its ability to cast the problem of RL as conditional sequence modeling. The core component of transformer is attention mechanism [44].
Offline Multi-Agent Reinforcement Learning with Knowledge Distillation, Lin Yen-Chen
We introduce an offline multi-agent reinforcement learning (offline MARL) framework that utilizes previously collected data without additional online data collection. Our method reformulates offline MARL as a sequence modeling problem and thus builds on top of the simplicity and scalability of the Transformer architecture. In the fashion of centralized training and decentralized execution, we propose to first train a teacher policy who has the privilege to access every agent's observations, actions, and rewards. After the teacher policy has identified and recombined the "good" behavior in the dataset, we create separate student policies and distill not only the teacher policy's features but also its structural relations among different agents' features to student policies. We show that our framework significantly improves performances on a range of tasks and outperforms state-of-the-art offline MARL baselines. Furthermore, we demonstrate that the proposed method has a better convergence rate, is more sample efficient, and is more robust to various demonstration qualities compared with baselines.