graph ae
FastGAE: Fast, Scalable and Effective Graph Autoencoders with Stochastic Subgraph Decoding
Salha, Guillaume, Hennequin, Romain, Remy, Jean-Baptiste, Moussallam, Manuel, Vazirgiannis, Michalis
Graph autoencoders (AE) and variational autoencoders (VAE) are powerful node embedding methods, but suffer from scalability issues. In this paper, we introduce FastGAE, a general framework to scale graph AE and VAE to large graphs with millions of nodes and edges. Our strategy, based on node sampling and subgraph decoding, significantly speeds up the training of graph AE and VAE while preserving or even improving performances. We demonstrate the effectiveness of FastGAE on numerous real-world graphs, outperforming the few existing approaches to scale graph AE and VAE by a wide margin.
Simple and Effective Graph Autoencoders with One-Hop Linear Models
Salha, Guillaume, Hennequin, Romain, Vazirgiannis, Michalis
Graph autoencoders (AE) and variational autoencoders (VAE) recently emerged as powerful node embedding methods, with promising performances on challenging tasks such as link prediction and node clustering. Graph AE, VAE and most of their extensions rely on graph convolutional networks (GCN) encoders to learn vector space representations of nodes. In this paper, we propose to replace the GCN encoder by a significantly simpler linear model w.r.t. the direct neighborhood (one-hop) adjacency matrix of the graph. For the two aforementioned tasks, we show that this approach consistently reaches competitive performances w.r.t. GCN-based models for numerous real-world graphs, including all benchmark datasets commonly used to evaluate graph AE and VAE. We question the relevance of repeatedly using these datasets to compare complex graph AE and VAE. We also emphasize the effectiveness of the proposed encoding scheme, that appears as a simpler and faster alternative to GCN encoders for many real-world applications.
Keep It Simple: Graph Autoencoders Without Graph Convolutional Networks
Salha, Guillaume, Hennequin, Romain, Vazirgiannis, Michalis
Graph autoencoders (AE) and variational autoencoders (V AE) recently emerged as powerful node embedding methods, with promising perform ances on challenging tasks such as link prediction and node clustering. Graph AE, V AE and most of their extensions rely on graph convolutional networks (G CN) to learn vector space representations of nodes. In this paper, we propose to replace the GCN encoder by a simple linear model w.r.t. the adjacency matrix of the graph. For the two aforementioned tasks, we empirically show that this app roach consistently reaches competitive performances w.r.t. GCN-based models for numerous real-world graphs, including the widely used Cora, Citeseer and P ubmed citation networks that became the de facto benchmark datasets for evaluating graph AE and V AE. This result questions the relevance of repeatedly usin g these three datasets to compare complex graph AE and V AE models. It also emphasizes t he effectiveness of simple node encoding schemes for many real-world applica tions.
Gravity-Inspired Graph Autoencoders for Directed Link Prediction
Salha, Guillaume, Limnios, Stratis, Hennequin, Romain, Tran, Viet Anh, Vazirgiannis, Michalis
Graph autoencoders (AE) and variational autoencoders (VAE) recently emerged as powerful node embedding methods. In particular, graph AE and VAE were successfully leveraged to tackle the challenging link prediction problem, aiming at figuring out whether some pairs of nodes from a graph are connected by unobserved edges. However, these models focus on undirected graphs and therefore ignore the potential direction of the link, which is limiting for numerous real-life applications. In this paper, we extend the graph AE and VAE frameworks to address link prediction in directed graphs. We present a new gravity-inspired decoder scheme that can effectively reconstruct directed graphs from a node embedding. We empirically evaluate our method on three different directed link prediction tasks, for which standard graph AE and VAE perform poorly. We achieve competitive results on three real-world graphs, outperforming several popular baselines.