activity
20092023
most citedFluid Models of Many-server Queues with Abandonment

44 citations · 93 across the 21 of their papers we have counts for

collaborators

21 papers

cs.LG2023

Stochastic Graph Bandit Learning with Side-Observations

Xueping Gong, Jiheng Zhang

In this paper, we investigate the stochastic contextual bandit with general function space and graph feedback. We propose an algorithm that addresses this problem by adapting to bo…

cs.LG2023

Efficient Transfer Learning via Causal Bounds

Xueping Gong, Wei You, Jiheng Zhang

Transfer learning seeks to accelerate sequential decision-making by leveraging offline data from related agents. However, data from heterogeneous sources that differ in observed fe…

cs.LG2023★ 2 cited

Debiasing Recommendation by Learning Identifiable Latent Confounders

Qing Zhang, Xiaoying Zhang, Yang Liu +4

Recommendation systems aim to predict users' feedback on items not exposed to them. Confounding bias arises due to the presence of unmeasured variables (e.g., the socio-economic st…

stat.ML2023★ 1 cited

Single-Trajectory Distributionally Robust Reinforcement Learning

Zhipeng Liang, Xiaoteng Ma, Jose Blanchet +2

To mitigate the limitation that the classical reinforcement learning (RL) framework heavily relies on identical training and test environments, Distributionally Robust RL (DRRL) ha…

cs.LG2022★ 2 cited

Optimal Contextual Bandits with Knapsacks under Realizability via Regression Oracles

Yuxuan Han, Jialin Zeng, Yang Wang +2

We study the stochastic contextual bandit with knapsacks (CBwK) problem, where each action, taken upon a context, not only leads to a random reward but also costs a random resource…

cs.LG2022

Dual Instrumental Method for Confounded Kernelized Bandits

Xueping Gong, Jiheng Zhang

The contextual bandit problem is a theoretically justified framework with wide applications in various fields. While the previous study on this problem usually requires independenc…

cs.LG2022★ 1 cited

Distributionally Robust Offline Reinforcement Learning with Linear Function Approximation

Xiaoteng Ma, Zhipeng Liang, Jose Blanchet +5

Among the reasons hindering reinforcement learning (RL) applications to real-world problems, two factors are critical: limited data and the mismatch between the testing environment…

cs.LG2022

On Private Online Convex Optimization: Optimal Algorithms in -Geometry and High Dimensional Contextual Bandits

Yuxuan Han, Zhicong Liang, Zhipeng Liang +3

Differentially private (DP) stochastic convex optimization (SCO) is ubiquitous in trustworthy machine learning algorithm design. This paper studies the DP-SCO problem with streamin…

cs.CR2021

Improving Blockchain Consistency Bound by Assigning Weights to Random Blocks

Qing Zhang, Xueping Gong, Huizhong Li +2

Blockchains based on the celebrated Nakamoto consensus protocol have shown promise in several applications, including cryptocurrencies. However, these blockchains have inherent sca…

stat.ML2021★ 6 cited

Generalized Linear Bandits with Local Differential Privacy

Yuxuan Han, Zhipeng Liang, Yang Wang +1

Contextual bandit algorithms are useful in personalized online decision-making. However, many applications such as personalized medicine and online advertising require the utilizat…

cs.DC2019★ 4 cited

Consensus Mechanism Design based on Structured Directed Acyclic Graphs

Jiahao He, Guangju Wang, Guangyuan Zhang +1

We introduce a structure for the directed acyclic graph (DAG) and a mechanism design based on that structure so that peers can reach consensus at large scale based on proof of work…

math.PR2018★ 2 cited

A Note on Many-server Fluid Models with Time-varying Arrivals

Zhenghua Long, Jiheng Zhang

We extend the measure-valued fluid model, which tracks residuals of patience and service times, to allow for time-varying arrivals. The fluid model can be characterized by a one-di…

math.PR2017

Heavy-traffic approximations for a layered network with limited resources

Angelos Aveklouris, Maria Vlasiou, Jiheng Zhang +1

Motivated by a web-server model, we present a queueing network consisting of two layers. The first layer incorporates the arrival of customers at a network of two single-server nod…

math.PR2016★ 3 cited

Instantaneous Control of Brownian Motion with a Positive Lead Time

Zhen Xu, Jiheng Zhang, Rachel Q. Zhang

Consider a storage system where the content is driven by a Brownian motion absent control. At any time, one may increase or decrease the content at a cost proportional to the amoun…

math.PR2014

Insensitivity of Proportional Fairness in Critically Loaded Bandwidth Sharing Networks

Maria Vlasiou, Jiheng Zhang, Bert Zwart

Proportional fairness is a popular service allocation mechanism to describe and analyze the performance of data networks at flow level. Recently, several authors have shown that th…

eess.SY2014

Approximations and Optimal Control for State-dependent Limited Processor Sharing Queues

Varun Gupta, Jiheng Zhang

The paper studies approximations and control of a processor sharing (PS) server where the service rate depends on the number of jobs occupying the server. The control of such a sys…

math.PR2014

Separation of timescales in a two-layered network

Maria Vlasiou, Jiheng Zhang, Bert Zwart

We investigate a computer network consisting of two layers occurring in, for example, application servers. The first layer incorporates the arrival of jobs at a network of multi-se…

math.PR2013

Convergence to Equilibrium States for Fluid Models of Many-server Queues with Abandonment

Zhenghua Long, Jiheng Zhang

Fluid models have become an important tool for the study of many-server queues with general service and patience time distributions. The equilibrium state of a fluid model has been…

math.PR2012★ 1 cited

A Unified Approach to Diffusion Analysis of Queues with General Patience-time Distributions

Junfei Huang, Hanqin Zhang, Jiheng Zhang

We propose a unified approach to establishing diffusion approximations for queues with impatient customers within a general framework of scaling customer patience time. The approac…

math.PR2009★ 27 cited

Diffusion limits of limited processor sharing queues

Jiheng Zhang, J. G. Dai, Bert Zwart

We consider a processor sharing queue where the number of jobs served at any time is limited to , with the excess jobs waiting in a buffer. We use random counting measures on th…

math.PR2009★ 44 cited

Fluid Models of Many-server Queues with Abandonment

Jiheng Zhang

We study many-server queues with abandonment in which customers have general service and patience time distributions. The dynamics of the system are modeled using measure- valued p…