A large portion of passenger requests is reportedly unserviced, partially due to vacant for-hire drivers' cruising behavior during the passenger seeking process. This paper aims to model the multi-driver repositioning task through a mean field multi-agent reinforcement learning (MARL) approach that captures competition among multiple agents. Because the direct application of MARL to the multi-driver system under a given reward mechanism will likely yield a suboptimal equilibrium due to the selfishness of drivers, this study proposes a reward design scheme with which a more desired equilibrium can be reached. To effectively solve the bilevel optimization problem with upper level as the reward design and the lower level as a multi-agent system, a Bayesian optimization (BO) algorithm is adopted to speed up the learning process. We then apply the bilevel optimization model to two case studies, namely, e-hailing driver repositioning under service charge and multiclass taxi driver repositioning under NYC congestion pricing. In the first case study, the model is validated by the agreement between the derived optimal control from BO and that from an analytical solution. With a simple piecewise linear service charge, the objective of the e-hailing platform can be increased by 8.4%. In the second case study, an optimal toll charge of $5.1 is solved using BO, which improves the objective of city planners by 7.9%, compared to that without any toll charge. Under this optimal toll charge, the number of taxis in the NYC central business district is decreased, indicating a better traffic condition, without substantially increasing the crowdedness of the subway system.
Order dispatching and driver repositioning (also known as fleet management) in the face of spatially and temporally varying supply and demand are central to a ride-sharing platform marketplace. Hand-crafting heuristic solutions that account for the dynamics in these resource allocation problems is difficult, and may be better handled by an end-to-end machine learning method. Previous works have explored machine learning methods to the problem from a high-level perspective, where the learning method is responsible for either repositioning the drivers or dispatching orders, and as a further simp…
LLM-ODDR: A Large Language Model Framework for Joint Order Dispatching and Driver Repositioning
Thrust of Artificial Intelligence, The Hong Kong University of Science and Technology (Guangzhou)(人工智能前沿技术 thrust,香港科学与技术大学(广州));Department of Aeronautical and Aviation Engineering, The Hong Kong Polytechnic University(航空与航空工程系,香港理工大学);Research Center for Low Altitude Economy, The Hong Kong Polytechnic University(低空经济研究中心,香港理工大学);Department of Computer Science and Engineering, The Hong Kong University of Science and Technology(计算机科学与工程系,香港科学与技术大学);Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology(土木与环境工程系,香港科学与技术大学)
DiDi Labs(滴滴实验室);Didi Chuxing(滴滴出行);University of Michigan(密歇根大学)
We present a new practical framework based on deep reinforcement learning and decision-time planning for real-world vehicle repositioning on ride-hailing (a type of mobility-on-demand, MoD) platforms. Our approach learns the spatiotemporal state-value function using a batch training algorithm with deep value networks. The optimal repositioning action is generated on-demand through value-based policy search, which combines planning and bootstrapping with the value networks. For the large-fleet problems, we develop several algorithmic features that we incorporate into our framework and that we d…
The University of Alabama(阿拉巴马大学);Purdue University(普渡大学)
In a ride-hailing system, an optimal relocation of vacant vehicles can significantly reduce fleet idling time and balance the supply-demand distribution, enhancing system efficiency and promoting driver satisfaction and retention. Model-free deep reinforcement learning (DRL) has been shown to dynamically learn the relocating policy by actively interacting with the intrinsic dynamics in large-scale ride-hailing systems. However, the issues of sparse reward signals and unbalanced demand and supply distribution place critical barriers in developing effective DRL models. Conventional exploration s…
Skip What You Can Predict: Predictive Repositioning for Policy Optimization for Efficient LLM Training
Bangladesh University of Engineering and Technology(孟加拉工程与技术大学);University of Maryland, College Park(马里兰大学学院公园分校);Illinois Institute of Technology(伊利诺伊理工学院);University of Central Florida(佛罗里达中央大学)
Electric Vehicle (EV) charging recommendation that both accommodates user preference and adapts to the ever-changing external environment arises as a cost-effective strategy to alleviate the range anxiety of private EV drivers. Previous studies focus on centralized strategies to achieve optimized resource allocation, particularly useful for privacy-indifferent taxi fleets and fixed-route public transits. However, private EV driver seeks a more personalized and resource-aware charging recommendation that is tailor-made to accommodate the user preference (when and where to charge) yet sufficient…
University of Virginia(弗吉尼亚大学);University of Illinois at Urbana Champaign(伊利诺伊大学厄巴纳-香槟分校);Rice University(莱斯大学)
Inspired by human visual attention, we propose a novel inverse reinforcement learning formulation using Maximum Entropy Deep Inverse Reinforcement Learning (MEDIRL) for predicting the visual attention of drivers in accident-prone situations. MEDIRL predicts fixation locations that lead to maximal rewards by learning a task-sensitive reward function from eye fixation patterns recorded from attentive drivers. Additionally, we introduce EyeCar, a new driver attention dataset in accident-prone situations. We conduct comprehensive experiments to evaluate our proposed model on three common benchmark…
Reinforcement learning (RL)-based driver assistance systems seek to improve fuel consumption via continual improvement of powertrain control actions considering experiential data from the field. However, the need to explore diverse experiences in order to learn optimal policies often limits the application of RL techniques in safety-critical systems like vehicle control. In this paper, an exponential control barrier function (ECBF) is derived and utilized to filter unsafe actions proposed by an RL-based driver assistance system. The RL agent freely explores and optimizes the performance object…
Columbia University(哥伦比亚大学);Didi Chuxing Inc.(滴滴出行有限公司);National Maglev Transportation Engineering R&D Center, Tongji University(同济大学国家磁浮交通工程技术研究中心);University of Michigan Transportation Research Institute, University of Michigan(密歇根大学密歇根大学交通研究所);Ford School of Public Policy, University of Michigan(密歇根大学福特公共政策学院)
Vacant taxi drivers' passenger seeking process in a road network generates additional vehicle miles traveled, adding congestion and pollution into the road network and the environment. This paper aims to employ a Markov Decision Process (MDP) to model idle e-hailing drivers' optimal sequential decisions in passenger-seeking. Transportation network companies (TNC) or e-hailing (e.g., Didi, Uber) drivers exhibit different behaviors from traditional taxi drivers because e-hailing drivers do not need to actually search for passengers. Instead, they reposition themselves so that the matching platfo…
Google Brain(谷歌大脑);Zhejiang University(浙江大学);Institut Mines-TELECOM(法国国立高等矿业电信学校联盟);TELECOM SudParis(南巴黎电信学院)
We consider the problem of learning to behave optimally in a Markov Decision Process when a reward function is not specified, but instead we have access to a set of demonstrators of varying performance. We assume the demonstrators are classified into one of k ranks, and use ideas from ordinal regression to find a reward function that maximizes the margin between the different ranks. This approach is based on the idea that agents should not only learn how to behave from experts, but also how not to behave from non-experts. We show there are MDPs where important differences in the reward functio…
Key Laboratory of Road and Traffic Engineering, Ministry of Education(教育部道路与交通工程重点实验室);School of Transportation Engineering, Tongji University(同济大学交通运输工程学院);Department of Civil and Environmental Engineering, University of Washington(华盛顿大学土木与环境工程系)
This study proposes a framework for human-like autonomous car-following planning based on deep reinforcement learning (deep RL). Historical driving data are fed into a simulation environment where an RL agent learns from trial and error interactions based on a reward function that signals how much the agent deviates from the empirical data. Through these interactions, an optimal policy, or car-following model that maps in a human-like way from speed, relative speed between a lead and following vehicle, and inter-vehicle spacing to acceleration of a following vehicle is finally obtained. The mo…
University of California, Berkeley(加州大学伯克利分校);Shanghai Jiaotong University(上海交通大学)
In the past decades, we have witnessed significant progress in the domain of autonomous driving. Advanced techniques based on optimization and reinforcement learning (RL) become increasingly powerful at solving the forward problem: given designed reward/cost functions, how should we optimize them and obtain driving policies that interact with the environment safely and efficiently. Such progress has raised another equally important question: \emph{what should we optimize}? Instead of manually specifying the reward functions, it is desired that we can extract what human drivers try to optimize …
Centre Borelli(博雷利中心);ENS Paris-Saclay(巴黎萨克雷高等师范学院);EDF Lab(法国电力公司实验室);CREST(法国国家科学研究中心经济学与统计学研究中心);ENSAE Paris(巴黎高等统计学院);Criteo AI Lab(Criteo人工智能实验室);LUISS(路易斯大学)
We study online learning for optimal allocation when the resource to be allocated is time. %Examples of possible applications include job scheduling for a computing server, a driver filling a day with rides, a landlord renting an estate, etc. An agent receives task proposals sequentially according to a Poisson process and can either accept or reject a proposed task. If she accepts the proposal, she is busy for the duration of the task and obtains a reward that depends on the task duration. If she rejects it, she remains on hold until a new task proposal arrives. We study the regret incurred by…
Novel advanced policy gradient (APG) algorithms, such as proximal policy optimization (PPO), trust region policy optimization, and their variations, have become the dominant reinforcement learning (RL) algorithms because of their ease of implementation and good practical performance. This dissertation is concerned with theoretical justification and practical application of the APG algorithms for solving processing network control optimization problems. Processing network control problems are typically formulated as Markov decision process (MDP) or semi-Markov decision process (SMDP) problems t…
The University of Queensland(昆士兰大学);Intuitive Surgical(直觉外科公司)
Multiple-Intent Inverse Reinforcement Learning (MI-IRL) seeks to find a reward function ensemble to rationalize demonstrations of different but unlabelled intents. Within the popular expectation maximization (EM) framework for learning probabilistic MI-IRL models, we present a warm-start strategy based on up-front clustering of the demonstrations in feature space. Our theoretical analysis shows that this warm-start solution produces a near-optimal reward ensemble, provided the behavior modes satisfy mild separation conditions. We also propose a MI-IRL performance metric that generalizes the po…
We propose and validate a novel car following model based on deep reinforcement learning. Our model is trained to maximize externally given reward functions for the free and car-following regimes rather than reproducing existing follower trajectories. The parameters of these reward functions such as desired speed, time gap, or accelerations resemble that of traditional models such as the Intelligent Driver Model (IDM) and allow for explicitly implementing different driving styles. Moreover, they partially lift the black-box nature of conventional neural network models. The model is trained on …
Tongji University(同济大学);University of Washington(华盛顿大学)
A model used for velocity control during car following was proposed based on deep reinforcement learning (RL). To fulfil the multi-objectives of car following, a reward function reflecting driving safety, efficiency, and comfort was constructed. With the reward function, the RL agent learns to control vehicle speed in a fashion that maximizes cumulative rewards, through trials and errors in the simulation environment. A total of 1,341 car-following events extracted from the Next Generation Simulation (NGSIM) dataset were used to train the model. Car-following behavior produced by the model wer…
Ubiquitous mobile computing have enabled ride-hailing services to collect vast amounts of behavioral data of riders and drivers and optimize supply and demand matching in real time. While these mobility service providers have some degree of control over the market by assigning vehicles to requests, they need to deal with the uncertainty arising from self-interested driver behavior since workers are usually free to drive when they are not assigned tasks. In this work, we formulate the problem of passenger-vehicle matching in a sparsely connected graph and proposed an algorithm to derive an equi…
GARLIC: GPT-Augmented Reinforcement Learning with Intelligent Control for Vehicle Dispatching
City University of Hong Kong(香港城市大学);Jilin University(吉林大学);Zhejiang University of Technology(浙江工业大学);Southern University of Science and Technology(南方科技大学);Harbin Institute of Technology (Shenzhen)(哈尔滨工业大学(深圳));Alibaba Group(阿里巴巴集团)
Wayne State University(韦恩州立大学);DiDi Research America(滴滴美国研究院);DiDi Research(滴滴研究院)
In this paper, we develop a reinforcement learning (RL) based system to learn an effective policy for carpooling that maximizes transportation efficiency so that fewer cars are required to fulfill the given amount of trip demand. For this purpose, first, we develop a deep neural network model, called ST-NN (Spatio-Temporal Neural Network), to predict taxi trip time from the raw GPS trip data. Secondly, we develop a carpooling simulation environment for RL training, with the output of ST-NN and using the NYC taxi trip dataset. In order to maximize transportation efficiency and minimize traffic …
The University of Queensland(昆士兰大学);Intuitive Surgical(直觉外科公司)
We provide new perspectives and inference algorithms for Maximum Entropy (MaxEnt) Inverse Reinforcement Learning (IRL), which provides a principled method to find a most non-committal reward function consistent with given expert demonstrations, among many consistent reward functions. We first present a generalized MaxEnt formulation based on minimizing a KL-divergence instead of maximizing an entropy. This improves the previous heuristic derivation of the MaxEnt IRL model (for stochastic MDPs), allows a unified view of MaxEnt IRL and Relative Entropy IRL, and leads to a model-free learning alg…
We demonstrate the first application of deep reinforcement learning to autonomous driving. From randomly initialised parameters, our model is able to learn a policy for lane following in a handful of training episodes using a single monocular image as input. We provide a general and easy to obtain reward: the distance travelled by the vehicle without the safety driver taking control. We use a continuous, model-free deep reinforcement learning algorithm, with all exploration and optimisation performed on-vehicle. This demonstrates a new framework for autonomous driving which moves away from rel…
Significant development of ride-sharing services presents a plethora of opportunities to transform urban mobility by providing personalized and convenient transportation while ensuring efficiency of large-scale ride pooling. However, a core problem for such services is route planning for each driver to fulfill the dynamically arriving requests while satisfying given constraints. Current models are mostly limited to static routes with only two rides per vehicle (optimally) or three (with heuristics). In this paper, we present a dynamic, demand aware, and pricing-based vehicle-passenger matching…
When learning to behave in a stochastic environment where safety is critical, such as driving a vehicle in traffic, it is natural for human drivers to plan fallback strategies as a backup to use if ever there is an unexpected change in the environment. Knowing to expect the unexpected, and planning for such outcomes, increases our capability for being robust to unseen scenarios and may help prevent catastrophic failures. Control of Autonomous Vehicles (AVs) has a particular interest in knowing when and how to use fallback strategies in the interest of safety. Due to imperfect information avail…
One of the key drivers of complexity in the classical (stochastic) multi-armed bandit (MAB) problem is the difference between mean rewards in the top two arms, also known as the instance gap. The celebrated Upper Confidence Bound (UCB) policy is among the simplest optimism-based MAB algorithms that naturally adapts to this gap: for a horizon of play n, it achieves optimal O(log n) regret in instances with "large" gaps, and a near-optimal O(\sqrt{n log n}) minimax regret when the gap can be arbitrarily "small." This paper provides new results on the arm-sampling behavior of UCB, leading to seve…
Sony Europe B.V., Schlieren/Switzerland Branch(索尼欧洲有限公司,施利伦/瑞士分公司);University of Zurich(苏黎世大学)
Autonomous car racing is a major challenge in robotics. It raises fundamental problems for classical approaches such as planning minimum-time trajectories under uncertain dynamics and controlling the car at the limits of its handling. Besides, the requirement of minimizing the lap time, which is a sparse objective, and the difficulty of collecting training data from human experts have also hindered researchers from directly applying learning-based approaches to solve the problem. In the present work, we propose a learning-based system for autonomous car racing by leveraging a high-fidelity phy…
Shared Control of Holonomic Wheelchairs through Reinforcement Learning
Swiss Paraplegic Research, SPF(瑞士瘫痪研究机构);SCAI Lab, D-HEST, Swiss Federal School of Technology in Zurich - ETH Zurich(SCAI实验室,瑞士联邦理工学院-苏黎世-ETH Zurich);Centre for Artificial Ingelligece, Zurich University of Applied Sciences - ZHAW. Switzerland(人工智能中心,瑞士应用科学大学-ZHAW)
Understanding electricity consumption behaviour through Inverse Reinforcement Learning
Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano(米兰理工大学电子、信息与生物工程系);Dipartimento di Ingegneria Gestionale, Politecnico di Milano(米兰理工大学管理工程系);RFF-CMCC European Institute on Economics and the Environment(RFF - CMCC欧洲经济与环境研究所);Centro Euro-Mediterraneo sui Cambiamenti Climatici(欧洲地中海气候变化中心)
For effective matching of resources (e.g., taxis, food, bikes, shopping items) to customer demand, aggregation systems have been extremely successful. In aggregation systems, a central entity (e.g., Uber, Food Panda, Ofo) aggregates supply (e.g., drivers, delivery personnel) and matches demand to supply on a continuous basis (sequential decisions). Due to the objective of the central entity to maximize its profits, individual suppliers get sacrificed thereby creating incentive for individuals to leave the system. In this paper, we consider the problem of learning approximate equilibrium soluti…
The large variety of digital payment choices available to consumers today has been a key driver of e-commerce transactions in the past decade. Unfortunately, this has also given rise to cybercriminals and fraudsters who are constantly looking for vulnerabilities in these systems by deploying increasingly sophisticated fraud attacks. A typical fraud detection system employs standard supervised learning methods where the focus is on maximizing the fraud recall rate. However, we argue that such a formulation can lead to sub-optimal solutions. The design requirements for these fraud models require…
RAST-MoE-RL: A Regime-Aware Spatio-Temporal MoE Framework for Deep Reinforcement Learning in Ride-Hailing
Massachusetts Institute of Technology(麻省理工学院);Tongji University(同济大学);University of California, Berkeley(加州大学伯克利分校);Carnegie Mellon University(卡内基梅隆大学);McGill University(麦吉尔大学);Northeastern University(东北大学)
Altruistic Ride Sharing: A Framework for Fair and Sustainable Urban Mobility via Peer-to-Peer Incentives
Dept. of CSIS and APPCAIR, BITS Pilani K K Birla Goa Campus(BITS Pilani K K Birla Goa校区计算机科学与信息系统系及应用人工智能中心);School of Computer Science, Carnegie Mellon University(卡内基梅隆大学计算机科学学院)
From $P(y|x)$ to $P(y)$: Investigating Reinforcement Learning in Pre-train Space
Institute of Automation, Chinese Academy of Sciences(中国科学院自动化研究所);University of Chinese Academy of Sciences(中国科学院大学);National University of Singapore(新加坡国立大学);Tencent AI Lab(腾讯AI实验室)
Using artificial intelligence (AI) to automatically test a game remains a critical challenge for the development of richer and more complex game worlds and for the advancement of AI at large. One of the most promising methods for achieving that long-standing goal is the use of generative AI agents, namely procedural personas, that attempt to imitate particular playing behaviors which are represented as rules, rewards, or human demonstrations. All research efforts for building those generative agents, however, have focused solely on playing behavior which is arguably a narrow perspective of wha…
Revisiting Entropy in Reinforcement Learning for Large Reasoning Models
TJUNLP Lab, School of Computer Science and Technology, Tianjin University, China(天津大学计算机科学与技术学院 TJUNLP 实验室,中国);Independent Researcher(独立研究者);College of Computer and Information Engineering, Tianjin Normal University, China(天津师范大学计算机与信息工程学院,中国)
Preference-Conditioned Multi-Objective Reinforcement Learning for Tactical Decision Making in Heavy-Duty Vehicles
Department of Computer Science and Engineering, Chalmers University of Technology and University of Gothenburg(计算机科学与工程系,查尔姆斯理工大学和哥德堡大学);Department of Mechanics and Maritime Sciences, Chalmers University of Technology(机械与海洋科学系,查尔姆斯理工大学)