no code implementations • 24 Apr 2024 • Ziheng Chen, Jia Wang, Jun Zhuang, Abbavaram Gowtham Reddy, Fabrizio Silvestri, Jin Huang, Kaushiki Nag, Kun Kuang, Xin Ning, Gabriele Tolomei
This bias emerges from two main sources: (1) data-level bias, characterized by uneven data removal, and (2) algorithm-level bias, which leads to the contamination of the remaining dataset, thereby degrading model accuracy.
1 code implementation • 17 Mar 2024 • Ziheng Chen, Yue Song, Yunmei Liu, Nicu Sebe
Using the deformation concept, we generalize the existing Lie groups on SPD manifolds into three families of parameterized Lie groups.
1 code implementation • 18 May 2023 • Ziheng Chen, Yue Song, Gaowen Liu, Ramana Rao Kompella, XiaoJun Wu, Nicu Sebe
Besides, our framework offers a novel intrinsic explanation for the most popular LogEig classifier in existing SPD networks.
no code implementations • 30 Apr 2023 • Ziheng Chen, Fabrizio Silvestri, Jia Wang, Yongfeng Zhang, Gabriele Tolomei
By reversing the learning process of the recommendation model, we thus develop a proficient greedy algorithm to generate fabricated user profiles and their associated interaction records for the aforementioned surrogate model.
no code implementations • 26 Mar 2023 • Ziheng Chen, Yue Song, Tianyang Xu, Zhiwu Huang, Xiao-Jun Wu, Nicu Sebe
Symmetric Positive Definite (SPD) matrices have received wide attention in machine learning due to their intrinsic capacity of encoding underlying structural correlation in data.
no code implementations • 4 Aug 2022 • Ziheng Chen, Fabrizio Silvestri, Jia Wang, Yongfeng Zhang, Zhenhua Huang, Hongshik Ahn, Gabriele Tolomei
Although powerful, it is very difficult for a GNN-based recommender system to attach tangible explanations of why a specific item ends up in the list of suggestions for a given user.
no code implementations • 16 Jun 2022 • Rui Wang, Xiao-Jun Wu, Ziheng Chen, Tianyang Xu, Josef Kittler
Image set-based visual classification methods have achieved remarkable performance, via characterising the image set in terms of a non-singular covariance matrix on a symmetric positive definite (SPD) manifold.
1 code implementation • 11 May 2022 • Ziheng Chen
Abstract In this work, we build two environments, namely the modified QLBS and RLOP models, from a mathematics perspective which enables RL methods in option pricing through replicating by portfolio.
1 code implementation • ACL 2022 • Xiao Li, Gong Cheng, Ziheng Chen, Yawei Sun, Yuzhong Qu
Recent machine reading comprehension datasets such as ReClor and LogiQA require performing logical reasoning over text.
1 code implementation • 25 Jan 2022 • Ziheng Chen, Tianyang Xu, Xiao-Jun Wu, Rui Wang, Zhiwu Huang, Josef Kittler
The Symmetric Positive Definite (SPD) matrices have received wide attention for data representation in many scientific areas.
1 code implementation • 22 Oct 2021 • Ziheng Chen, Fabrizio Silvestri, Jia Wang, He Zhu, Hongshik Ahn, Gabriele Tolomei
However, existing CF generation methods either exploit the internals of specific models or depend on each sample's neighborhood, thus they are hard to generalize for complex models and inefficient for large datasets.
no code implementations • 14 Feb 2021 • Ziheng Chen, Jin Huang, Hongshik Ahn, Xin Ning
We consider the problem of costly feature classification, where we sequentially select the subset of features to make a balance between the classification error and the feature cost.
no code implementations • 11 Nov 2019 • Ziheng Chen, Hongshik Ahn
In this article, we propose a novel probabilistic framework to improve the accuracy of a weighted majority voting algorithm.