How to mix Confronting “mixed” NP models and bilinguals' choices

The widespread occurrence of nouns in one language with a determiner in the other, often referred to as mixed NPs, has generated much theorizing and debate. Since both a syntactic account based on abstract features of the determiner and an account highlighting the notion of a Matrix language yield largely the same predictions, we assess how the tenets of each play out in speaker choices. The data derive from a massive corpus of spontaneous nominal mixes, produced by bilinguals in New Mexico, where bidirectional code-switching is the norm. Bilinguals' choices concern (1) NP status (mixed vs. unmixed); (2) mixing type (limited-item vs. multi-word); and (3) language of the noun (here, English vs. Spanish). Results show that the community preference is for mixed NPs, independent of their theoretical felicity as dictated by determiner language properties. As to mixing type, these NPs are mostly constituted of lone nouns, such that the language of the determiner and any associated verb is perforce that of the surrounding discourse. Finally, the overwhelming choice is for English lone nouns incorporated into Spanish, and hence for a Spanish determiner. The language of the determiner thus proceeds, not from abstract linguistic properties, but instead from straightforward adherence to bilingual speech community conventions.