arXiv AI

Representable but Unlearned: Encoding Rank and the Interaction-Prediction Floor

The paper investigates how input encodings constrain the set of contrasts a predictor can reproduce, even when no individual contrast is forced to zero. By computing the attainable contrast space from an encoder’s equivalence classes and a fixed contrast design—without using labels, loss, or a fitted model—the authors derive an empirical error floor for any unrestricted decoder on those classes. Experiments on a 140‑rectangle siRNA interaction panel show that a graph neural network’s training‑only feature mask reduces the rank of interaction contrasts from 140 to 72, creating a floor of 0.009980 (14.6% of the fitted model’s interaction squared error). Removing the mask eliminates the floor but only marginally improves MSE, while restoring chemistry columns recovers full rank. A separate RNA‑splicing predictor with an injective encoding achieves full rank and a zero floor, illustrating that the encoding itself, not the model, limits recoverable contrast space.

arXiv AI
Aug 19

No Gaussian Required: Contrastive Inverse Dynamics for JEPA World Models

The paper introduces Action-Contrastive Masked Transition Modeling (AC‑MTM), a method that replaces the Gaussian regularizer used in Joint‑Embedding Predictive Architectures (JEPAs) with a contrastive inverse‑dynamics head. AC‑MTM trains a forward latent‑prediction model while an auxiliary inverse‑dynamics task forces the encoder to distinguish actions from latent transitions, preventing collapse without requiring a target network or reconstruction loss. Experiments on pixel‑control and multi‑object visual tasks show that AC‑MTM matches or surpasses the performance of the Gaussian‑based SIGReg regularizer, achieving up to 20–24 point improvements on the OGBench Visual Scene benchmark.

By Jack Boylan, Chris Hokamp
arXiv Machine Learning
Sep 21

Certified Topological Interaction in Neural Representations: Exact Tests and the Statistic They Require

The paper introduces the Intersection Euler Characteristic Profile, a topological metric for measuring class overlap in neural representations, and provides exact permutation and sign‑flip tests to assess disentanglement across layers. Using this statistic, the authors analyze 111 networks and 52,650 measurements, finding that disentanglement is depth‑graded, occurs early, and is influenced by training choices such as augmentation and weight decay. The study also demonstrates that the unnormalized mass of the profile predicts test accuracy, while the dimensionless quotient does not outperform simple linear probes.

By Sushovan Majhi
arXiv Machine Learning
Aug 31

Locked Evaluation Surfaces: Transfer Failure and Sampling-Depth Entanglement in CRISPRi Perturbation-Effect Prediction

The study evaluates a frozen Geneformer representation for predicting CRISPRi perturbation effects under a tightly controlled, pre‑registered protocol. While the representation shows significant predictive power within the Virtual Cell Challenge dataset, it fails to transfer to external screens, with negative zero‑shot Spearman correlations. The analysis also reveals that the VCC endpoint is heavily influenced by sampling depth, as cell count alone explains most of the variance, indicating a sampling‑depth entanglement that could mask transfer failures in less controlled settings.

By Mehrdad Shoeibi, Niloofar Yousefi
arXiv Computer Vision
Sep 3

Breaking the Geometric Bottleneck: Contrastive Expansion in Asymmetric Cross-Modal Distillation

The paper investigates how knowledge distillation from Vision Transformers to smaller CNNs can cause dimensional collapse in the student’s representation space. Using SVD and Shannon entropy, the authors show that cosine‑based distillation leads to a drastic reduction in effective rank, while adding an InfoNCE objective can double the rank but harms downstream accuracy due to signal dilution. They further demonstrate that a label‑aware contrastive objective (Supervised Contrastive distillation) can maintain or improve accuracy without unnecessary rank expansion, indicating that effective rank alone is not a reliable indicator of representation quality.

By Kabir Thayani
arXiv Computer Vision
Aug 25

EXPL-FR: Explaining Face Recognition Models via Vision-Language Alignment

EXPL-FR is a lightweight adapter that aligns a vision‑language model’s image encoder with a frozen face‑recognition (FR) embedding space, enabling the FR model to be explained using semantic attribute prompts without any text training. By mapping 978 attribute prompts across 22 categories into the FR space, the method identifies the most detectable concepts—forming a readable semantic signature that better separates identities than the full vocabulary. The approach is evaluated on four FR backbones and two VLM encoders, providing identity‑level, per‑image, and differential explanations, and demonstrates that prompt‑driven audits can rank FR models by per‑ethnicity error and attribute‑change verification cost without requiring labeled data.

By Guray Ozgur, Mustafa Efe Tamyapar, Naser Damer, Fadi Boutros
Hugging Face Trending Papers
Aug 18

No Gaussian Required: Contrastive Inverse Dynamics for JEPA World Models

The paper introduces Action-Contrastive Masked Transition Modeling (AC‑MTM), a method that stabilizes Joint‑Embedding Predictive Architectures (JEPAs) without relying on Gaussian regularization. AC‑MTM adds a training‑only inverse‑dynamics head that uses Action‑NCE to force each latent transition to identify its generating action, thereby preventing encoder collapse. Experiments on pixel‑control and multi‑object visual tasks show that AC‑MTM trains stably from scratch and matches or surpasses the performance of SIGReg, achieving up to a 24‑point improvement on the OGBench Visual Scene benchmark.