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Title: Batch Active Learning with Graph Neural Networks via Multi-Agent Deep Reinforcement Learning
Graph neural networks (GNNs) have achieved tremendous success in many graph learning tasks such as node classifica- tion, graph classification and link prediction. For the classifi- cation task, GNNs’ performance often highly depends on the number of labeled nodes and thus could be significantly ham- pered due to the expensive annotation cost. The sparse litera- ture on active learning for GNNs has primarily focused on se- lecting only one sample each iteration, which becomes ineffi- cient for large scale datasets. In this paper, we study the batch active learning setting for GNNs where the learning agent can acquire labels of multiple samples at each time. We formu- late batch active learning as a cooperative multi-agent rein- forcement learning problem and present a novel reinforced batch-mode active learning framework (BIGENE). To avoid the combinatorial explosion of the joint action space, we in- troduce a value decomposition method that factorizes the to- tal Q-value into the average of individual Q-values. More- over, we propose a novel multi-agent Q-network consisting of a graph convolutional network (GCN) component and a gated recurrent unit (GRU) component. The GCN compo- nent takes both the informativeness and inter-dependences between nodes into account and the GRU component enables more » the agent to consider interactions between selected nodes in the same batch. Experimental results on multiple public datasets demonstrate the effectiveness and efficiency of our proposed method. « less
Award ID(s):
1947135 2134079
Publication Date:
Journal Name:
AAAI 2022
Sponsoring Org:
National Science Foundation
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