arXiv AI
Oct 9

Discovering Global False Negatives On the Fly for Self-supervised Contrastive Learning

The paper introduces GloFND, an optimization-based method that learns a threshold for each anchor image during training to automatically detect false negative pairs in self-supervised contrastive learning. Unlike prior approaches that only consider false negatives within a mini-batch, GloFND globally identifies them across the entire dataset while keeping per-iteration computation independent of dataset size. Experiments on image and image-text data show the method’s effectiveness, and the implementation is publicly available.

By Vicente Balmaseda, Bokun Wang, Ching-Long Lin, Tianbao Yang
arXiv AI
Oct 9

From Pixels, Without Pre-training: Joint Generative and Self-Supervised Representation Learning in One Model

The paper introduces SCION, a single-model framework that jointly learns generative and self‑supervised representation tasks without relying on labels or pretrained encoders. SCION uses a pixel‑space encoder conditioned on a flow timestep and a shared embedding, training contrastive and flow‑matching objectives simultaneously with gradient‑norm balancing and stop‑gradient techniques. On ImageNet 256×256, SCION achieves state‑of‑the‑art FID scores (8.92 with JiT‑B and 5.89/3.47 with JiT‑L) surpassing prior class‑unconditional and pretrained‑conditioned methods.

By Vicente Balmaseda, Ching-Long Lin, Tianbao Yang