Jumping knowledge (JK) combines representations from multiple graph-convolution layers instead of relying only on the final layer. This lets the model use neighborhood information from different depths and adapt the effective receptive field for each node. section 3.2.2
Two-layer GCN
A CustomGCN applies two GCNConv layers, stores the activated first-layer output and second-layer output, then combines both with JumpingKnowledge(mode='cat').
