arXiv Machine Learning

Relative Prime Factorization and Finite-State Presentations under Fixed Finite-Monoid Observation

The paper investigates exact factorization and canonical presentations of languages relative to a fixed finite‑monoid observation. It shows that unique factorization does not guarantee a finite relative presentation property (FRP) by presenting a 36‑element quotient with infinite valid prime‑return rules, and introduces the stronger finite‑state relative presentation property (FSRP). The authors further define prime‑target left‑division determinism (PTLD), prove its implications for factorization and rule bounds, and provide efficient learning algorithms for the canonical PTLD presentation and FSRP controller.

arXiv Machine Learning
Oct 22

A Reverse-Gold Theorem: Positive-Data Identification by Substrate-Bounded Contrastive Learners

The paper presents a positive result contrasting Gold’s theorem by showing that a learner equipped with a recursive contrast operator and a bounded-capacity InfoNCE-style scorer can achieve PAC conditional identification from positive data alone. Under a faithfulness condition, the trained scorer ranks almost all positives above any out-of-language perturbation within their orbit, with polynomial sample complexity in the operator’s capacity, orbit size, score bound, and error tolerance. The method constructs negatives internally, avoids global normalization, and extends to a membership classifier and a normalization-free Metropolis–Hastings generator, with instantiations for substitutable context‑free and subregular languages. whyItMatters":"The work demonstrates that contrastive learning can overcome classical limits on language identification by positive data, offering a concrete, sample‑efficient framework for learning structured language classes without external negative examples."

By Rakesh Sengupta
arXiv Computation and Language
Oct 23

Finitely Verifiable Segmentation: Decidability for Every Tokenizer with a Finite-State Verifier

The paper introduces the notion of finitely verifiable segmentation, where a finite automaton accepts exactly the segmentations produced by a given policy. It proves that several key decision problems—such as boundary certification, bounded gaps, mask completable generation, and policy equivalence—become decidable for this class, which lies strictly between online‑scannable and regular‑domain policies. The class is closed under common pipeline operations and supports practical implementations like maximal‑munch lexing and WordPiece, with all results accompanied by executable checks.

By Nicklas Nidh\"ogg
arXiv AI
Aug 14

Algebraic Decomposition Theory for Transformer Length Generalization

arXiv:2608. 13433v1 Announce Type: cross Abstract: Transformer-based language models are known to sometimes generalize to sequences longer than seen during training, but we lack a precise characterization of which tasks admit length generalization.

By Andy Yang, Blerta Veseli, Corentin Barloy, Micha\"el Cadilhac, Andreas Krebs, Charles Paperman, Howard Straubing, Michael Hahn
arXiv Machine Learning
Aug 12

Power law graph attention: exact generalization of scaled dot-product attention, empirical collapse at inference

arXiv:2608. 10288v1 Announce Type: new Abstract: The Large Language Model from Power Law Decoder Representations (PLDR-LLM) and its attention, Power Law Graph Attention (PLGA), replace the fixed bilinear form of scaled dot-product attention (SDPA) with a learned, input-generated bilinear operator $G_{LM}$, built from a positive tensor $A_{LM}$ by elementwise power laws.

By Burc Gokden