Length Generalization with Log-Depth Recurrent Units
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Abstract (arXiv)
Length generalization remains a persistent challenge for neural networks: recurrent models tend to suffer from positional biases, while transformers are constrained by fixed computational depth. Regular languages provide a frequently used testbed for evaluating length generalization, as label prediction can be checked for any sequence length. We propose MLP-LDRU, a type of Log-Depth Recurrent Unit, which captures a class of associativity-biased operators designed to approximate recurrence through parallel reduction. We evaluate MLP-LDRU on 21 regular-language tasks, consisting of standard benchmarks and new prefix languages, where it achieves 100% out-of-distribution accuracy on 18 tasks and at least 99.9% on the remaining 3 when increasing max training length, outperforming comparable recurrent and attention-based models. We further evaluate MLP-LDRU beyond regular languages on ListOps and NLP classification benchmarks, where it performs competitively.
Key facts. Cited by 1 paper in the map (data through 7 Oct 2026). Builds on 53 of its 79 references that are in the map. First posted on arXiv 25 May 2026.
Builds on
53 of 79 references.
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Citing papers per year: 2026: 1.
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- 2026Log-Depth Recurrent Language Modelingcited by 0
- 2026Log-Depth Recurrent Language Modeling23 Sep 2026