Charu Aggarwal


2023

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Distance-Based Propagation for Efficient Knowledge Graph Reasoning
Harry Shomer | Yao Ma | Juanhui Li | Bo Wu | Charu Aggarwal | Jiliang Tang
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing

Knowledge graph completion (KGC) aims to predict unseen edges in knowledge graphs (KGs), resulting in the discovery of new facts. A new class of methods have been proposed to tackle this problem by aggregating path information. These methods have shown tremendous ability in the task of KGC. However they are plagued by efficiency issues. Though there are a few recent attempts to address this through learnable path pruning, they often sacrifice the performance to gain efficiency. In this work, we identify two intrinsic limitations of these methods that affect the efficiency and representation quality. To address the limitations, we introduce a new method, TAGNet, which is able to efficiently propagate information. This is achieved by only aggregating paths in a fixed window for each source-target pair. We demonstrate that the complexity of TAGNet is independent of the number of layers. Extensive experiments demonstrate that TAGNet can cut down on the number of propagated messages by as much as 90% while achieving competitive performance on multiple KG datasets.

2020

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SetConv: A New Approach for Learning from Imbalanced Data
Yang Gao | Yi-Fan Li | Yu Lin | Charu Aggarwal | Latifur Khan
Proceedings of the 2020 Conference on Empirical Methods in Natural Language Processing (EMNLP)

For many real-world classification problems, e.g., sentiment classification, most existing machine learning methods are biased towards the majority class when the Imbalance Ratio (IR) is high. To address this problem, we propose a set convolution (SetConv) operation and an episodic training strategy to extract a single representative for each class, so that classifiers can later be trained on a balanced class distribution. We prove that our proposed algorithm is permutation-invariant despite the order of inputs, and experiments on multiple large-scale benchmark text datasets show the superiority of our proposed framework when compared to other SOTA methods.