Evolving Computation Graphs

Graph neural networks (GNNs) have demonstrated success in modeling relational data, especially for data that exhibits homophily: when a connection between nodes tends to imply that they belong to the same class. However, while this assumption is true in many relevant situations, there are important real-world scenarios that violate this assumption. In this work, we propose Evolving Computation Graphs (ECGs), a novel method for enhancing GNNs on heterophilic datasets without requiring prior domain knowledge. Our approachbuilds on prior theoretical insights linking node degree, high homophily, and inter vs intra-class embedding similarity by rewiring the GNNs’ computation graph towards adding edges that connect nodes that are likely to be in the same class. We utilise weaker classifiers to identify these edges and evaluate ECGs on a diverse set of recently-proposed heterophilous datasets, demonstrating improvements over 95% of the relevant baselines.