Cross-Linguistic and Socioeconomic Differences in the Use of Variation Sets in Children's Communicative Environments.

This study examines variation sets (VS) - structured repetitions of words in different morphosyntactic contexts - in child-directed speech (CDS) compared to adult-directed speech (ADS) across two communities (Argentinian Spanish and North American English) and socioeconomic groups. Drawing on naturalistic recordings from 101 families, results show that VS are more frequent in CDS than in ADS. In Argentinian Spanish, they are more prevalent in middle socioeconomic status (SES) households, whereas no SES-related differences emerged in the North American sample. Across languages, they were often anchored in verbs. However, SES-related differences in lexical anchoring varied by community: in Argentinian middle-SES households, CDS includes more VS anchored in adjectives, whereas in middle-SES North American English households, noun-based VS were less frequent relative to verb-based VS. Findings indicate that linguistic typology - particularly the pro-drop versus non-pro-drop distinction - and socioeconomic context are associated with the lexical distribution and organization of repetition with variation in children's everyday linguistic environments.