aiqbench analysis
This research introduces a novel geometric framework for analyzing second-language pronunciation by projecting speech representations into a native-reference coordinate system derived from self-supervised features. By eliminating the need for matched native recordings or explicit labels, the method effectively quantifies acoustic-phonetic deviations that correlate strongly with speaking proficiency metrics. The approach advances automatic speech assessment by providing interpretable measures of pronunciation quality directly from spontaneous learner speech.
A Native-Reference Phone-Class Geometry for Second-Language Pronunciation Analysis
arXiv:2609.30075v1 Announce Type: new Abstract: Automatic speaking assessment systems can provide holistic proficiency scores, but often lack interpretable measures that characterize pronunciation quality. We propose a native-reference phone-class geometry for measuring second language (L2) pronunciation deviation without requiring pronunciation labels, read-aloud prompts, or matched recordings of the same text from native and L2 speakers. Given a native speech corpus, we average frame-level self-supervised representations for each context-dependent phone-class and use singular value decomposition (SVD) to derive a compact native-reference coordinate system. For each L2 utterance, we compute the corresponding averages and project them into the native-reference space. We then demonstrate that the distances between L2 and native-reference coordinates for matched phone-classes show consistent negative correlations with holistic speaking proficiency on the Dev subset of the Speak and Improve Corpus 2025 (Spearman's $\rho\!=\!-0.53$) and with pronunciation quality on the learner subset of the English Read by Japanese Students dataset ($\rho\!=\!-0.34$). These findings suggest that the proposed geometry captures acoustic-phonetic information relevant for proficiency rating while remaining applicable to spontaneous L2 speech without matched native recordings.
Abstract:Automatic speaking assessment systems can provide holistic proficiency scores, but often lack interpretable measures that characterize pronunciation quality. We propose a native-reference phone-class geometry for measuring second language (L2) pronunciation deviation without requiring pronunciation labels, read-aloud prompts, or matched recordings of the same text from native and L2 speakers. Given a native speech corpus, we average frame-level self-supervised representations for each context-dependent phone-class and use singular value decomposition (SVD) to derive a compact native-reference coordinate system. For each L2 utterance, we compute the corresponding averages and project them into the native-reference space. We then demonstrate that the distances between L2 and native-reference coordinates for matched phone-classes show consistent negative correlations with holistic speaking proficiency on the Dev subset of the Speak and Improve Corpus 2025 (Spearman's $\rho\!=\!-0.53$) and with pronunciation quality on the learner subset of the English Read by Japanese Students dataset ($\rho\!=\!-0.34$). These findings suggest that the proposed geometry captures acoustic-phonetic information relevant for proficiency rating while remaining applicable to spontaneous L2 speech without matched native recordings.
Computation and Language (cs.CL); Sound (cs.SD)
arXiv:2609.30075 [cs.CL]
(or arXiv:2609.30075v1 [cs.CL] for this version)
https://doi.org/10.48550/arXiv.2609.30075 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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