The Effect of Forms’ Ratio of Conditioning on Word-Final /s/ Voicing in Mexican Spanish

Abstract

There is mounting evidence that words that occur proportionately more often in contexts that condition a phonetically-motivated sound change end up changing more rapidly than other words. Support has been found in at least modern-day Spanish, Medieval Spanish, bilingual English-Spanish, and modern-day English. This study tests whether there is support for this idea with regards to the variable voicing of word-final /s/ in Spanish. An analysis of 1431 tokens of word-final /s/ spoken by 15 female speakers of Mexican Spanish living in Salinas, California, USA is performed. The response variable is the percentage of the /s/ segment that is voiced, and the effect of a handful of predictor variables shown in the literature to condition /s/ voicing is investigated. The variable of interest is forms’ ratio of conditioning (FRC), or the proportion of times with which word types occur in the context that conditions voicing of word-final /s/. The results of a series of 40 beta regression models indicate that FRC significantly conditions the percentage of voicing of word-final /s/ in these data. Also, the effect of manipulating two aspects of FRC operationalization is analyzed. This study adds to the growing body of literature documenting the importance of cumulative contextual information in the mental representation of words.