Graph Neural Networks Are More Powerful Than we Think

  title={Graph Neural Networks Are More Powerful Than we Think},
  author={Charilaos I. Kanatsoulis and Alejandro Ribeiro},
Graph Neural Networks (GNNs) are powerful convolutional architectures that have shown remarkable performance in various node-level and graph-level tasks. Despite their success, the common belief is that the expressive power of GNNs is limited and that they are at most as discriminative as the Weisfeiler-Lehman (WL) algorithm. In this paper we argue the opposite and show that the WL algorithm is the upper bound only when the input to the GNN is the vector of all ones. In this direction, we… 
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