RecSys 2026 · – · Room “Trees”

Transformer models for recommendation

Transformer-based
Sequential Recommender Systems

From user histories to next-item predictions: an introduction to sequence models, their training objectives, and the choices that shape evaluation and serving.

Jan Malte Lichtenberg Aleksandr V. Petrov

The slides include interactive model playgrounds. For offline use, unzip the download and open tutorial/index.html in your browser.

Programme

Block 1

Foundations and SASRec

Sequential recommendation, chronological data preparation, item embeddings, causal self-attention, and next-item training. SASRec and a small MovieLens example make the model’s computations inspectable.

Block 2

Objectives, evaluation, and scale

Training objectives and BERT4Rec, evaluation choices, large item catalogs, content representations, cold start, serving, and recent directions in generative recommendation.

Audience and preparation

For researchers and practitioners familiar with basic recommendation and machine-learning concepts. No prior experience with sequential recommenders is required.

Bring a laptop to try the playgrounds. Models run in your browser; no account, software installation, or inference service is needed.

Citation

BibTeX

If you use these tutorial materials, please cite:

@inproceedings{lichtenberg2026transformer,
  title={Transformer-based Sequential Recommender Systems},
  author={Lichtenberg, Jan Malte and Petrov, Aleksandr V},
  booktitle={Proceedings of the 20th ACM Conference on Recommender Systems},
  pages={1911--1912},
  year={2026}
}