HT-Transformer: Event Sequences Classification by Accumulating Prefix Information with History Tokens

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Karpukhin, Ivan, Savchenko, Andrey
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866913972426375168
author Karpukhin, Ivan
Savchenko, Andrey
author_facet Karpukhin, Ivan
Savchenko, Andrey
contents Deep learning has achieved remarkable success in modeling sequential data, including event sequences, temporal point processes, and irregular time series. Recently, transformers have largely replaced recurrent networks in these tasks. However, transformers often underperform RNNs in classification tasks where the objective is to predict future targets. The reason behind this performance gap remains largely unexplored. In this paper, we identify a key limitation of transformers: the absence of a single state vector that provides a compact and effective representation of the entire sequence. Additionally, we show that contrastive pretraining of embedding vectors fails to capture local context, which is crucial for accurate prediction. To address these challenges, we introduce history tokens, a novel concept that facilitates the accumulation of historical information during next-token prediction pretraining. Our approach significantly improves transformer-based models, achieving impressive results in finance, e-commerce, and healthcare tasks. The code is publicly available on GitHub.
format Preprint
id arxiv_https___arxiv_org_abs_2508_01474
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle HT-Transformer: Event Sequences Classification by Accumulating Prefix Information with History Tokens
Karpukhin, Ivan
Savchenko, Andrey
Machine Learning
Deep learning has achieved remarkable success in modeling sequential data, including event sequences, temporal point processes, and irregular time series. Recently, transformers have largely replaced recurrent networks in these tasks. However, transformers often underperform RNNs in classification tasks where the objective is to predict future targets. The reason behind this performance gap remains largely unexplored. In this paper, we identify a key limitation of transformers: the absence of a single state vector that provides a compact and effective representation of the entire sequence. Additionally, we show that contrastive pretraining of embedding vectors fails to capture local context, which is crucial for accurate prediction. To address these challenges, we introduce history tokens, a novel concept that facilitates the accumulation of historical information during next-token prediction pretraining. Our approach significantly improves transformer-based models, achieving impressive results in finance, e-commerce, and healthcare tasks. The code is publicly available on GitHub.
title HT-Transformer: Event Sequences Classification by Accumulating Prefix Information with History Tokens
topic Machine Learning
url https://arxiv.org/abs/2508.01474