In this study, we tackle three main challenges of deep sequential processing models in previous research: (1) memory degradation, (2) inaccurate gradient backpropagation, and (3) compatibility with next-token prediction. Specifically, to address (1-2), we define a Flashback property in which memory is preserved perfectly as an identity mapping of its stored value in a memory region until it is overwritten by a hidden state at a different time step. We propose a Flashback mechanism that satisfies this property in a fully differentiable, end-to-end manner. Further, to tackle (3), we propose architectures that incorporate the Flashback mechanism into Transformers and Mamba, enabling next-token prediction for language modeling tasks. In experiments, we trained on The Pile dataset, which includes diverse texts, to evaluate tradeoffs between commonsense reasoning accuracy, processing speed, and memory usage after introducing the Flashback mechanism into existing methods. The evaluations confirmed the effectiveness of the Flashback mechanism.

This paper presents Text2Traj2Text, a novel learning-by-synthesis framework for captioning possible contexts behind shopper’s trajectory data in retail stores. Our work will impact various retail applications that need better customer understanding, such as targeted advertising and inventory management. The key idea is leveraging large language models to synthesize a diverse and realistic collection of contextual captions as well as the corresponding movement trajectories on a store map. Despite learned from fully synthesized data, the captioning model can generalize well to trajectories/captions created by real human subjects. Our systematic evaluation confirmed the effectiveness of the proposed framework over competitive approaches in terms of ROUGE and BERT Score metrics.