SnapE -- Training Snapshot Ensembles of Link Prediction Models
Ali Shaban, Heiko Paulheim
TL;DR
The paper tackles the challenge of robust link prediction in sparse knowledge graphs by employing snapshot ensembles (SnapE) within the same training budget as a single model. It adapts cyclic learning-rate schedules to store multiple diverse snapshots and introduces an extended negative sampling strategy that uses prior snapshots to generate hard negatives, while combining predictions via normalization and weighting. Across four datasets and four base KGEs, SnapE delivers consistent improvements over single-model baselines and offers favorable trade-offs compared to low-dimensional ensemble approaches, without increasing training cost. The work also analyzes runtime, diversity of models, and ablations, outlining directions for broader applicability to other graph methods and downstream tasks.
Abstract
Snapshot ensembles have been widely used in various fields of prediction. They allow for training an ensemble of prediction models at the cost of training a single one. They are known to yield more robust predictions by creating a set of diverse base models. In this paper, we introduce an approach to transfer the idea of snapshot ensembles to link prediction models in knowledge graphs. Moreover, since link prediction in knowledge graphs is a setup without explicit negative examples, we propose a novel training loop that iteratively creates negative examples using previous snapshot models. An evaluation with four base models across four datasets shows that this approach constantly outperforms the single model approach, while keeping the training time constant.
