Negative-Aware Diffusion Process for Temporal Knowledge Graph Extrapolation
Yanglei Gan, Peng He, Yuxiang Cai, Run Lin, Guanyu Zhou, Qiao Liu
TL;DR
NADEx addresses two core gaps in diffusion-based Temporal Knowledge Graph extrapolation: neglect of informative negative context and reliance on generic reconstruction losses. It encodes subject-centric histories, applies forward diffusion to target embeddings, and uses a Transformer-based denoiser conditioned on temporal-relational context, augmented by a cosine-alignment regularizer built from batch-wise negative prototypes. Empirical results on ICEWS14, ICEWS18, ICEWS05-15, and GDELT show state-of-the-art performance, with strong gains on unseen events and data-scarce scenarios, while maintaining efficient inference. This work advances generative TK reasoning by producing calibrated, discriminative predictions that effectively model temporal dynamics under uncertainty.
Abstract
Temporal Knowledge Graph (TKG) reasoning seeks to predict future missing facts from historical evidence. While diffusion models (DM) have recently gained attention for their ability to capture complex predictive distributions, two gaps remain: (i) the generative path is conditioned only on positive evidence, overlooking informative negative context, and (ii) training objectives are dominated by cross-entropy ranking, which improves candidate ordering but provides little supervision over the calibration of the denoised embedding. To bridge this gap, we introduce Negative-Aware Diffusion model for TKG Extrapolation (NADEx). Specifically, NADEx encodes subject-centric histories of entities, relations and temporal intervals into sequential embeddings. NADEx perturbs the query object in the forward process and reconstructs it in reverse with a Transformer denoiser conditioned on the temporal-relational context. We further derive a cosine-alignment regularizer derived from batch-wise negative prototypes, which tightens the decision boundary against implausible candidates. Comprehensive experiments on four public TKG benchmarks demonstrate that NADEx delivers state-of-the-art performance.
