ProDiff: Prototype-Guided Diffusion for Minimal Information Trajectory Imputation
This addresses trajectory imputation for applications relying on incomplete data, offering a novel approach that reduces data requirements compared to existing methods.
The paper tackles trajectory data imputation with minimal information (only two endpoints) by proposing ProDiff, which integrates prototype learning and diffusion models. It outperforms state-of-the-art methods with accuracy improvements of 6.28% on FourSquare and 2.52% on WuXi, and shows a 0.927 correlation with real trajectories.
Trajectory data is crucial for various applications but often suffers from incompleteness due to device limitations and diverse collection scenarios. Existing imputation methods rely on sparse trajectory or travel information, such as velocity, to infer missing points. However, these approaches assume that sparse trajectories retain essential behavioral patterns, which place significant demands on data acquisition and overlook the potential of large-scale human trajectory embeddings. To address this, we propose ProDiff, a trajectory imputation framework that uses only two endpoints as minimal information. It integrates prototype learning to embed human movement patterns and a denoising diffusion probabilistic model for robust spatiotemporal reconstruction. Joint training with a tailored loss function ensures effective imputation. ProDiff outperforms state-of-the-art methods, improving accuracy by 6.28\% on FourSquare and 2.52\% on WuXi. Further analysis shows a 0.927 correlation between generated and real trajectories, demonstrating the effectiveness of our approach.