Ensemble Model with BERT, RoBERTa and XLNet for Molecular Property Prediction
Research Article  ·  Published: 06 August 2026
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ICCK Transactions on Emerging Topics in Artificial Intelligence
Volume 3, Issue 3, 2026: 170-187
Research Article Open Access

Ensemble Model with BERT, RoBERTa and XLNet for Molecular Property Prediction

1 School of Intelligent Manufacturing, Chongqing Jianzhu College, Chongqing 400072, China
* Corresponding Author: Junling Hu, [email protected]
Volume 3, Issue 3

Article Information

Abstract

Molecular property prediction is a fundamental task in drug discovery and materials science, yet most high-performing approaches depend on large-scale pretraining that demands substantial computational resources. This work proposes a pretraining-free ensemble framework that trains multiple Transformer-based architectures—BERT, RoBERTa, and XLNet—from random initialization using the Atom-in-SMILES (AIS) molecular representation, which provides richer atomic-level semantics than conventional SMILES. The three Transformer encoders are coupled with BiLSTM prediction heads and integrated via a BaggingRegressor to reduce variance and improve generalization. Experiments on the ZINC250k and ZINC310k benchmarks demonstrate that the proposed framework achieves competitive performance against pretrained baselines including GROVER, CHEM-BERT, and D-MPNN, while requiring only task-specific end-to-end training with adaptive early stopping. These results establish that carefully designed molecular representations combined with heterogeneous ensemble learning can serve as a practical and resource-efficient alternative to pretraining-based paradigms in molecular modeling.

Graphical Abstract

Ensemble Model with BERT, RoBERTa and XLNet for Molecular Property Prediction

Keywords

ensemble learning BERT RoBERTa XLNet molecular property prediction

Data Availability Statement

The code and data supporting the findings of this study are openly available on GitHub at https://github.com/jlinghu/AIS-Ensemble-model.

Funding

This work was supported without any funding.

Conflicts of Interest

The author declares no conflicts of interest.

AI Use Statement

The author declares that no generative AI was used in the preparation of this manuscript.

Ethical Approval and Consent to Participate

Not applicable. This study is purely computational and does not involve human participants, animal subjects, or identifiable personal data. No ethical approval or informed consent was required.

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Cite This Article

APA Style
Hu, J. (2026). Ensemble Model with BERT, RoBERTa and XLNet for Molecular Property Prediction. ICCK Transactions on Emerging Topics in Artificial Intelligence, 3(3), 170-187. https://doi.org/10.62762/TETAI.2026.604672
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TY  - JOUR
AU  - Hu, Junling
PY  - 2026
DA  - 2026/08/06
TI  - Ensemble Model with BERT, RoBERTa and XLNet for Molecular Property Prediction
JO  - ICCK Transactions on Emerging Topics in Artificial Intelligence
T2  - ICCK Transactions on Emerging Topics in Artificial Intelligence
JF  - ICCK Transactions on Emerging Topics in Artificial Intelligence
VL  - 3
IS  - 3
SP  - 170
EP  - 187
DO  - 10.62762/TETAI.2026.604672
UR  - https://www.icck.org/article/abs/TETAI.2026.604672
KW  - ensemble learning
KW  - BERT
KW  - RoBERTa
KW  - XLNet
KW  - molecular property prediction
AB  - Molecular property prediction is a fundamental task in drug discovery and materials science, yet most high-performing approaches depend on large-scale pretraining that demands substantial computational resources. This work proposes a pretraining-free ensemble framework that trains multiple Transformer-based architectures—BERT, RoBERTa, and XLNet—from random initialization using the Atom-in-SMILES (AIS) molecular representation, which provides richer atomic-level semantics than conventional SMILES. The three Transformer encoders are coupled with BiLSTM prediction heads and integrated via a BaggingRegressor to reduce variance and improve generalization. Experiments on the ZINC250k and ZINC310k benchmarks demonstrate that the proposed framework achieves competitive performance against pretrained baselines including GROVER, CHEM-BERT, and D-MPNN, while requiring only task-specific end-to-end training with adaptive early stopping. These results establish that carefully designed molecular representations combined with heterogeneous ensemble learning can serve as a practical and resource-efficient alternative to pretraining-based paradigms in molecular modeling.
SN  - 3068-6652
PB  - Institute of Central Computation and Knowledge
LA  - English
ER  - 
BibTeX Format
Compatible with LaTeX, BibTeX, and other reference managers
@article{Hu2026Ensemble,
  author = {Junling Hu},
  title = {Ensemble Model with BERT, RoBERTa and XLNet for Molecular Property Prediction},
  journal = {ICCK Transactions on Emerging Topics in Artificial Intelligence},
  year = {2026},
  volume = {3},
  number = {3},
  pages = {170-187},
  doi = {10.62762/TETAI.2026.604672},
  url = {https://www.icck.org/article/abs/TETAI.2026.604672},
  abstract = {Molecular property prediction is a fundamental task in drug discovery and materials science, yet most high-performing approaches depend on large-scale pretraining that demands substantial computational resources. This work proposes a pretraining-free ensemble framework that trains multiple Transformer-based architectures—BERT, RoBERTa, and XLNet—from random initialization using the Atom-in-SMILES (AIS) molecular representation, which provides richer atomic-level semantics than conventional SMILES. The three Transformer encoders are coupled with BiLSTM prediction heads and integrated via a BaggingRegressor to reduce variance and improve generalization. Experiments on the ZINC250k and ZINC310k benchmarks demonstrate that the proposed framework achieves competitive performance against pretrained baselines including GROVER, CHEM-BERT, and D-MPNN, while requiring only task-specific end-to-end training with adaptive early stopping. These results establish that carefully designed molecular representations combined with heterogeneous ensemble learning can serve as a practical and resource-efficient alternative to pretraining-based paradigms in molecular modeling.},
  keywords = {ensemble learning, BERT, RoBERTa, XLNet, molecular property prediction},
  issn = {3068-6652},
  publisher = {Institute of Central Computation and Knowledge}
}

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