1 code implementation • 14 Jul 2024 • Muyao Niu, Tong Chen, Yifan Zhan, Zhuoxiao Li, Xiang Ji, Yinqiang Zheng
Neural Radiance Fields (NeRFs) have become increasingly popular because of their impressive ability for novel view synthesis.
2 code implementations • 26 Jun 2024 • Mathieu Fourment, Matthew Macaulay, Christiaan J Swanepoel, Xiang Ji, Marc A Suchard, Frederick A Matsen IV
Furthermore, we explore the use of the forward KL divergence as an optimizing criterion for variational inference, which can handle discontinuous and non-differentiable models.
no code implementations • 6 Jun 2024 • Xiang Ji, Sanjeev Kulkarni, Mengdi Wang, Tengyang Xie
This work studies the challenge of aligning large language models (LLMs) with offline preference data.
1 code implementation • CVPR 2024 • Xiang Ji, Haiyang Jiang, Yinqiang Zheng
Experiment results have verified the effectiveness of our proposed algorithm, as well as the validity of our dual imaging setting.
no code implementations • 16 Oct 2023 • Zihao Li, Xiang Ji, Minshuo Chen, Mengdi Wang
In fact, human preference data are now used with classic reinforcement learning algorithms such as actor-critic methods, which involve evaluating an intermediate policy over a reward learned from human preference data with distribution shift, known as off-policy evaluation (OPE).
no code implementations • 15 Oct 2023 • Yulong Yang, Chenhao Lin, Xiang Ji, Qiwei Tian, Qian Li, Hongshan Yang, Zhibo Wang, Chao Shen
Instead, a one-shot adversarial augmentation prior to training is sufficient, and we name this new defense paradigm Data-centric Robust Learning (DRL).
no code implementations • 25 Sep 2023 • Zhenghao Xu, Xiang Ji, Minshuo Chen, Mengdi Wang, Tuo Zhao
As a result, by properly choosing the network size and hyperparameters, NPMD can find an $\epsilon$-optimal policy with $\widetilde{O}(\epsilon^{-\frac{d}{\alpha}-2})$ samples in expectation, where $\alpha\in(0, 1]$ indicates the smoothness of environment.
no code implementations • 3 Aug 2023 • Chenhao Lin, Xiang Ji, Yulong Yang, Qian Li, Chao Shen, Run Wang, Liming Fang
Adversarial training (AT) is widely considered the state-of-the-art technique for improving the robustness of deep neural networks (DNNs) against adversarial examples (AE).
no code implementations • 24 Jul 2023 • Xiang Ji, Huazheng Wang, Minshuo Chen, Tuo Zhao, Mengdi Wang
A popular approach is to utilize human feedback to learn a reward function for training.
no code implementations • 3 Jul 2023 • Xiang Ji, Jiaxin Wei, Yifu Wang, Huiliang Shang, Laurent Kneip
Visual place recognition is an important problem towards global localization in many robotics tasks.
no code implementations • NeurIPS 2023 • Xiang Ji, Gen Li
A crucial problem in reinforcement learning is learning the optimal policy.
2 code implementations • 23 Mar 2023 • Andrew F. Magee, Andrew J. Holbrook, Jonathan E. Pekar, Itzue W. Caviedes-Solis, Fredrick A. Matsen IV, Guy Baele, Joel O. Wertheim, Xiang Ji, Philippe Lemey, Marc A. Suchard
Phylogenetic and discrete-trait evolutionary inference depend heavily on an appropriate characterization of the underlying character substitution process.
no code implementations • ICCV 2023 • Xiang Ji, Zhixiang Wang, Shin'ichi Satoh, Yinqiang Zheng
Image degradation often occurs during fast camera or object movements, regardless of the exposure modes: global shutter (GS) or rolling shutter (RS).
no code implementations • ICCV 2023 • Xiang Ji, Zhixiang Wang, Zhihang Zhong, Yinqiang Zheng
Image restoration from various motion-related degradations, like blurry effects recorded by a global shutter (GS) and jello effects caused by a rolling shutter (RS), has been extensively studied.
1 code implementation • CVPR 2023 • Zhihang Zhong, Mingdeng Cao, Xiang Ji, Yinqiang Zheng, Imari Sato
This paper studies the challenging problem of recovering motion from blur, also known as joint deblurring and interpolation or blur temporal super-resolution.
1 code implementation • 9 Nov 2022 • Christiaan Swanepoel, Mathieu Fourment, Xiang Ji, Hassan Nasif, Marc A Suchard, Frederick A Matsen IV, Alexei Drummond
Probabilistic programming frameworks are powerful tools for statistical modelling and inference.
2 code implementations • 3 Nov 2022 • Mathieu Fourment, Christiaan J. Swanepoel, Jared G. Galloway, Xiang Ji, Karthik Gangavarapu, Marc A. Suchard, Frederick A. Matsen IV
Gradients of probabilistic model likelihoods with respect to their parameters are essential for modern computational statistics and machine learning.
no code implementations • 24 Oct 2022 • Xiang Ji, Yesim Sungu-Eryilmaz, Elaheh Momeni, Reza Rawassizadeh
Natural language processing applications, such as conversational agents and their question-answering capabilities, are widely used in the real world.
no code implementations • 6 Jun 2022 • Xiang Ji, Minshuo Chen, Mengdi Wang, Tuo Zhao
We consider the off-policy evaluation problem of reinforcement learning using deep convolutional neural networks.
1 code implementation • CVPR 2022 • Zhixiang Wang, Xiang Ji, Jia-Bin Huang, Shin'ichi Satoh, Xiao Zhou, Yinqiang Zheng
In this paper, we investigate using rolling shutter with a global reset feature (RSGR) to restore clean global shutter (GS) videos.
no code implementations • 31 Jan 2022 • Chengzhuo Ni, Ruiqi Zhang, Xiang Ji, Xuezhou Zhang, Mengdi Wang
Policy gradient (PG) estimation becomes a challenge when we are not allowed to sample with the target policy but only have access to a dataset generated by some unknown behavior policy.
1 code implementation • 25 Oct 2021 • Xiang Ji, Alexander A. Fisher, Shuo Su, Jeffrey L. Thorne, Barney Potter, Philippe Lemey, Guy Baele, Marc A. Suchard
Divergence time estimation is crucial to provide temporal signals for dating biologically important events, from species divergence to viral transmissions in space and time.
1 code implementation • ACL 2021 • Yixin Cao, Xiang Ji, Xin Lv, Juanzi Li, Yonggang Wen, Hanwang Zhang
We present InferWiki, a Knowledge Graph Completion (KGC) dataset that improves upon existing benchmarks in inferential ability, assumptions, and patterns.
no code implementations • 3 Mar 2021 • Andrew J. Holbrook, Xiang Ji, Marc A. Suchard
Mutations sometimes increase contagiousness for evolving pathogens.
no code implementations • 6 Feb 2021 • Botao Hao, Xiang Ji, Yaqi Duan, Hao Lu, Csaba Szepesvári, Mengdi Wang
Bootstrapping provides a flexible and effective approach for assessing the quality of batch reinforcement learning, yet its theoretical property is less understood.
1 code implementation • 20 Oct 2020 • Xinyu Ma, Jiafeng Guo, Ruqing Zhang, Yixing Fan, Xiang Ji, Xueqi Cheng
Recently pre-trained language representation models such as BERT have shown great success when fine-tuned on downstream tasks including information retrieval (IR).
no code implementations • 21 Aug 2020 • Sheng Liu, Zuo-Jun Max Shen, Xiang Ji
We formalize the bike lane planning problem in view of the cyclists' utility functions and derive an integer optimization model to maximize the utility.
1 code implementation • 20 Apr 2020 • Xiangyu Zhu, Zhenbo Luo, Pei Fu, Xiang Ji
Then we use orientation and camera similarity as penalty to get final similarity.
1 code implementation • 29 May 2019 • Xiang Ji, Zhen-Yu Zhang, Andrew Holbrook, Akihiko Nishimura, Guy Baele, Andrew Rambaut, Philippe Lemey, Marc A. Suchard
To make this tractable, we present a linear-time algorithm for ${\cal O}\hspace{-0. 2em}\left( N \right)$-dimensional gradient evaluation and apply it to general continuous-time Markov processes of sequence substitution on a phylogenetic tree without a need to assume either stationarity or reversibility.
Computation Populations and Evolution Methodology
1 code implementation • 24 May 2019 • Jiafeng Guo, Yixing Fan, Xiang Ji, Xue-Qi Cheng
Text matching is the core problem in many natural language processing (NLP) tasks, such as information retrieval, question answering, and conversation.