About Me

Hello there! I’m a Postdoctoral Researcher in the Department of Computer Science and Engineering at the University of California, Riverside, where I’m mentored by Prof. Vagelis Papalexakis. My current work focuses on developing machine learning methods to address challenges in precision agriculture.

Prior to UCR, I completed my PhD in Computer Science and Computational Mathematics at the University of São Paulo, under Prof. Alneu de Andrade Lopes where I developed graph reduction methods aimed at improving the efficiency and scalability of graph-based learning systems.

Research Interests:

  • Graph Machine Learning
  • Data-Centric AI and Representation Learning
  • Large-Scale Data and Model Compression
  • Efficient and Scalable AI Systems
  • AI for Precision Agriculture

Selected Publications

Multi-view Graph Condensation via Tensor Decomposition
Nícolas Roque dos Santos, Dawon Ahn, Diego Minatel, Alneu de Andrade Lopes, and Evangelos E. Papalexakis
Proceedings of WSDM, 2026  [paper]

One-mode Projection of Bipartite Graphs for Text Classification using Graph Neural Networks
Nícolas Roque dos Santos, Diego Minatel, and Alan Demétrius Baria Valejo
Proceedings of ACM/SIGAPP SAC, 2025  [paper]

Semi-Supervised Coarsening of Bipartite Graphs for Text Classification via Graph Neural Network
Nícolas Roque dos Santos, Diego Minatel, Alan Demétrius Baria Valejo, and Alneu de Andrade Lopes
IEEE DSAA, 2024  [paper]

Spectral Regularization for Diffusion Models
Satish Chandran*, Nícolas Roque dos Santos*, Yunshu Wu, Greg Ver Steeg, and Evangelos E. Papalexakis (*Equal contribution)
Preprint, 2026  [paper]

FairDIF: Debiasing Classifiers with Item Response Theory and Differential Item Functioning
Diego Minatel, Antonio Rafael Sabino Parmezan, Nícolas Roque dos Santos, Mariana Cúri, Ricardo Bastos Cavalcante Prudêncio, and Alneu de Andrade Lopes
AI and Ethics, 2026  [paper]

Unfairness in Machine Learning for Web Systems Applications
Diego Minatel, Nícolas Roque dos Santos, Angelo Cesar Mendes da Silva, Mariana Cúri, Ricardo Marcondes Marcacini, and Alneu de Andrade Lopes
WebMedia, 2023  [paper]

News

  • [Mar 2026] Paper accepted at WSDM 2026: Multi-view Graph Condensation via Tensor Decomposition
  • [Feb 2026] Preprint out: Spectral Regularization for Diffusion Models
  • [Jan 2026] Paper accepted at AI and Ethics: FairDIF: Debiasing Classifiers with Item Response Theory and Differential Item Functioning
  • [Jan 2025] Started as a Postdoctoral Researcher at the University of California, Riverside
  • [Dec 2025] Paper accepted at BRACIS 2025: Graph Condensation for Text Classification