arXiv Computation and Language By Nir Yarden, Amit Ben-Artzy, Roy Schwartz

Beyond State Capacity: Why Retrieval Breaks in Mamba

Read the original on arXiv Computation and Language →

The paper investigates why Mamba models underperform Transformers on in-context retrieval tasks. It challenges the common belief that Mamba’s fixed-size recurrent state limits retrieval, showing that even when the query precedes the context, Mamba still lags behind Transformers. The study reveals that Mamba’s selection gates can strongly influence output, but they rely on relevance signals that only emerge gradually with depth, causing a retrieval bottleneck beyond state capacity.

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