Previous hypergraph expansions are solely carried out on either vertex level or hyperedge level, thereby missing the symmetric nature of data co-occurrence, and resulting in information loss. To address the problem, this paper treats vertices and hyperedges equally and proposes a new hypergraph formulation named the \emph{line expansion (LE)} for hypergraphs learning. The new expansion bijectively induces a homogeneous structure from the hypergraph by treating vertex-hyperedge pairs as "line nodes". By reducing the hypergraph to a simple graph, the proposed \emph{line expansion} makes existing graph learning algorithms compatible with the higher-order structure and has been proven as a unifying framework for various hypergraph expansions. We evaluate the proposed line expansion on five hypergraph datasets, the results show that our method beats SOTA baselines by a significant margin.
@article{arxiv.2005.04843,
title = {Semi-supervised Hypergraph Node Classification on Hypergraph Line Expansion},
author = {Chaoqi Yang and Ruijie Wang and Shuochao Yao and Tarek Abdelzaher},
journal= {arXiv preprint arXiv:2005.04843},
year = {2023}
}