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Technique of Augmenting Molecular Graph Data by Perturbating Hidden Features.

Takahiro Inoue1, Kenichi Tanaka1, Kimito Funatsu1,2

  • 1Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.

Molecular Informatics
|January 10, 2022
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Summary

This study introduces a novel graph data augmentation technique for graph neural networks (GNNs). This method enhances GNN performance, especially on small datasets, by adding random perturbations during message passing.

Keywords:
ChemoinformaticsData augmentationGraph neural networkStructure-property relationshipsVirtual screening

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Area of Science:

  • Computational chemistry
  • Machine learning
  • Drug discovery

Background:

  • Quantitative structure-property relationship (QSPR) models are crucial for identifying molecules with specific properties in drug discovery and materials science.
  • Graph neural networks (GNNs) have demonstrated strong predictive performance in QSPR modeling.
  • Training GNNs typically requires large datasets, posing a challenge for studies with limited samples.

Purpose of the Study:

  • To develop an effective data augmentation method for GNNs applicable to small datasets.
  • To improve the feature extraction capabilities of GNNs when training data is scarce.
  • To enhance the prediction performance of GNNs in quantitative structure-property relationship tasks.

Main Methods:

  • A novel graph data augmentation technique was designed by introducing random perturbations to vertex features during the message passing phase of GNNs.
  • The proposed method was evaluated on both regression and classification tasks.
  • The effectiveness of data augmentation was analyzed based on the timing of perturbation addition within the GNN architecture.

Main Results:

  • The proposed data augmentation method proved effective in enhancing GNN performance for QSPR modeling.
  • Perturbations were most impactful when applied immediately before the readout layer of the GNN.
  • The benefits of this data augmentation approach were most pronounced on small datasets, particularly those with around 1000 samples.

Conclusions:

  • The developed graph data augmentation method offers a viable solution for improving GNN performance with limited data.
  • This technique is particularly valuable for accelerating drug discovery and materials development processes where large datasets may not be available.
  • The findings highlight the potential of targeted data augmentation strategies in advancing machine learning applications in chemistry.