Keigo Sakurai

Laboratory of Media Creation Methodology

Hokkaido University

Sapporo, Japan

sakurai [at] lmd.ist.hokudai.ac.jp

I am an Assistant Professor at Hokkaido University, working with the Laboratory of Media Creation Methodology. I received my Ph.D. in Information Science from Hokkaido University in September 2025, where I was a JSPS Research Fellow (DC1).

My research focuses on data mining centered on recommender systems, applied across multiple domains including music, finance, and fashion. Currently, I am particularly interested in graph-based recommendation, sequential recommendation, generative retrieval and recommendation, explainability, and the use of large language models for recommendation in various domains.

My work has been published in premiere venues such as SIGIR, RecSys, WSDM, CIKM, ECIR, and ISMIR. I am a member of ACM, IEEE, the Japanese Society for Artificial Intelligence (JSAI), and the Information Processing Society of Japan (IPSJ).

日本語のプロフィールはこちら。

news

Aug 11, 2026	Two papers on graph collaborative filtering and sequential recommendation are accepted to CIKM 2026.
Jul 11, 2026	One paper on elucidating the last item-reliance effects in sequential recommendation is accepted to RecSys 2026.
Apr 02, 2026	One paper on sequential recommendation with self-attention is accepted to SIGIR 2026.
Apr 01, 2026	I started as an Assistant Professor at the Faculty of Information Science and Technology, Hokkaido University!
Nov 29, 2025	One paper on utility-aware financial asset recommendation is accepted to WSDM 2026.

selected publications

CIKM

The Edge Spectrum of Choice-Derived Item Graphs: Strong and Weak Edges Encode Different Relations in Collaborative Filtering

Keigo Sakurai, Takahiro Ogawa, and Miki Haseyama

In Proceedings of the ACM International Conference on Information and Knowledge Management (CIKM), 2026

Bib

@inproceedings{sakurai2026cikm,
  title = {The Edge Spectrum of Choice-Derived Item Graphs: Strong and Weak Edges Encode Different Relations in Collaborative Filtering},
  author = {Sakurai, Keigo and Ogawa, Takahiro and Haseyama, Miki},
  booktitle = {Proceedings of the ACM International Conference on Information and Knowledge Management (CIKM)},
  year = {2026}
}

RecSys

Explaining Last-Item Reliance in Causal Self-Attention for Sequential Recommendation via Residual Dominance

Keito Kozaki, Keigo Sakurai, Ren Togo, and 2 more authors

In Proceedings of the ACM Conference on Recommender Systems (RecSys), 2026

Bib

@inproceedings{kozaki2026recsys,
  title = {Explaining Last-Item Reliance in Causal Self-Attention for Sequential Recommendation via Residual Dominance},
  author = {Kozaki, Keito and Sakurai, Keigo and Togo, Ren and Ogawa, Takahiro and Haseyama, Miki},
  booktitle = {Proceedings of the ACM Conference on Recommender Systems (RecSys)},
  year = {2026},
}

SIGIR

Revisiting the Role of Learned Attention Weighting in SASRec

Keito Kozaki, Keigo Sakurai, Ren Togo, and 2 more authors

In Proceedings of the International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR), 2026

Bib

@inproceedings{kozaki2026sigir,
  title = {Revisiting the Role of Learned Attention Weighting in SASRec},
  author = {Kozaki, Keito and Sakurai, Keigo and Togo, Ren and Ogawa, Takahiro and Haseyama, Miki},
  booktitle = {Proceedings of the International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR)},
  pages = {3894--3899},
  year = {2026},
}

WSDM

Risk-Aware Utility Re-Ranking for Financial Asset Recommendation

Keigo Sakurai, Takahiro Ogawa, Miki Haseyama, and 2 more authors

In Proceedings of the ACM International Conference on Web Search and Data Mining (WSDM), 2026

Bib

@inproceedings{sakurai2026wsdm,
  title = {Risk-Aware Utility Re-Ranking for Financial Asset Recommendation},
  author = {Sakurai, Keigo and Ogawa, Takahiro and Haseyama, Miki and Anan, A. and Nakagawa, Kei},
  booktitle = {Proceedings of the ACM International Conference on Web Search and Data Mining (WSDM)},
  pages = {1227--1231},
  year = {2026},
}

ECIR

LLM Is Knowledge Graph Reasoner: LLM’s Intuition-Aware Knowledge Graph Reasoning for Cold-Start Sequential Recommendation

Keigo Sakurai, Ren Togo, Takahiro Ogawa, and 1 more author

In Proceedings of the European Conference on Information Retrieval (ECIR), 2025

Bib

@inproceedings{sakurai2025ecir,
  title = {LLM Is Knowledge Graph Reasoner: LLM's Intuition-Aware Knowledge Graph Reasoning for Cold-Start Sequential Recommendation},
  author = {Sakurai, Keigo and Togo, Ren and Ogawa, Takahiro and Haseyama, Miki},
  booktitle = {Proceedings of the European Conference on Information Retrieval (ECIR)},
  pages = {263--278},
  year = {2025},
}

ISMIR

MMT-BERT: Chord-Aware Symbolic Music Generation Based on Multitrack Music Transformer and MusicBERT

Jinlong Zhu, Keigo Sakurai, Ren Togo, and 2 more authors

In Proceedings of the International Society for Music Information Retrieval Conference (ISMIR), 2024

Bib

@inproceedings{zhu2024ismir,
  title = {MMT-BERT: Chord-Aware Symbolic Music Generation Based on Multitrack Music Transformer and MusicBERT},
  author = {Zhu, Jinlong and Sakurai, Keigo and Togo, Ren and Ogawa, Takahiro and Haseyama, Miki},
  booktitle = {Proceedings of the International Society for Music Information Retrieval Conference (ISMIR)},
  pages = {470--477},
  year = {2024},
}