El book or the libro? Insights from acceptability judgments into determiner/noun code

We used two types of acceptability judgments to experimentally test the predictions of two theoretical models of code-switching regarding the surface realization of the determiner in nominal constructions: lexicalist approaches within the Minimalist Program (MP) versus the Bilingual NP Hypothesis within the Matrix Language Frame Model (MLF). Two separate groups of 40 early Spanish-English bilinguals evaluated the acceptability of sentences with code-switches between the determiner and the noun that reflected the predictions of the MP model, the MLF, of both or none. The first group rated them on a Likert scale, while the second group performed a two-alternative forced-choice acceptability task (2AFC). Ratings from the Likert ratings were subjected to an analysis of variance while results from the 2AFC were analyzed using Thurstone’s Law of Comparative Judgment. Both experiments yielded converging evidence supporting the predictions of the MLF. Results from the 2AFC provided a more detailed picture that suggests also a (smaller) contribution of the language of the determiner. This is the first study to use acceptability judgments to directly contrast the predictions of these major theoretical models regarding switches between determiner and noun. An additional novelty is the use of the 2AFC and Thurstone’s Law of Comparative Judgment, which yielded a more detailed picture than the more commonly used Likert-scale ratings. Our results provide further support for Eppler, Luescher, and Deuchar’s recent claim that we can only advance our understanding of grammaticality in code-switching if we combine the insights of the different frameworks rather than considering them in isolation