Trusting self-evaluation: predicting music and language performance from subjective ratings.

Introduction: Subjective self-evaluation is frequently used to assess perceived musical and linguistic competence, but the extent to which such ratings correspond to objectively measured performance, particularly across domains, remains unclear. Methods: A total of 104 participants completed objective music tasks assessing singing, melodic discrimination, mistuning perception, and beat perception; language tasks assessing expressive reading, speech imitation, and auditory phonological pattern recognition; and multi-item self-evaluation scales for both domains. Associations were examined using correlation analyses, hierarchical regression models, and Bland-Altman analyses. Results: Subjective self-evaluation and objective performance were moderately associated within both domains but were not interchangeable. Objective music and language performance predicted one another more strongly than cross-domain self-evaluations. Within-domain self-evaluation contributed additional variance to the corresponding performance models. Bland-Altman analyses indicated negligible mean bias at the group level but substantial individual disagreement. Discussion: Subjective self-evaluation and objective performance capture complementary but theoretically distinct aspects of musical and linguistic ability. Objective assessment therefore remains necessary when performance itself is the target, whereas self-evaluation provides additional information about perceived competence. Comparable cross-domain association patterns are consistent with partly shared mechanisms across music and language.