Variation and Processing of Subject Contact Relatives: A Comparison of AAL and MAE

Subject contact relatives (SCRs) are relative clauses that do not require an overt complementizer (e.g., that, which) and where the relative clause is a subject-extracted relative clause. For example, “The girl bought the leash is looking for the dogs” would be a subject contact relative, whereas “The dogs (that) the girl found are happy” would be an object contact relative. In African American Language (AAL) both subject and object contact relatives are present, but Mainstream American English (MAE) only the object contact relative is allowed. The central question of this dissertation is how speakers of comprehend complex structures that are present or not present in their dialect. To do this, I complete three experiments. In Chapter 2, I complete a judgment study to establish how the SCR structure is distributed in the community of AAL speakers that I work with. SCRs can occur in a variety of different forms that are not consistent cross-linguistically. Therefore, it was important to determine what types of SCRs the community of speakers allowed and disallowed. In this chapter, I find that there is a unimodal rather than a bimodal distribution in acceptance of the different types of SCRs. It could have been the case that members of the community do allow SCRs, but they could have accepted different types of SCRs. However, what I observed is that of the three different SCR classes tested, AAL comprehenders found them all to be acceptable. In Chapter 3, I turn to computational modeling to investigate how predictive lan- guage modeling might account for SCRs when the language models are trained on mostly MAE language data. I complete two experiments. First, modeled after work done by Aina and Linzen (2021), I manipulate the length of the text preamble to un- derstand whether, and if so how, a off-the-shelf language model can make predicted continuations for SCRs. For example, and ambiguous preamble would be “Alisha was the one handed the chair ” because it could continue as a SCR (e.g., Alisha was the one handed the chair to the magician) or as a reduced relative clause (e.g., Alisha was the one handed the chair by the magician). What I find is that the language models are capable of producing text continuations in line with an SCR structure, but do so at a low and inconsistent rate, especially compared to other the unambiguous pream- bles. The second experiment in this chapter focuses on computational parsing, and I complete several parsing studies to investigate how a computational parser might as- sign structure to the SCR as well as whether augmentation of representative samples (i.e., including toy SCR examples) in the training data influence performance. Once again, the models are capable of assigning relations in line with an SCR structure, but do so at a low rate. This rate does improve when toy examples are included in the training data. Lastly, I move onto human studies in Chapter 4. This chapter focuses on how speakers of AAL and MAE comprehend the SCR. I use a visual world paradigm study and manipulate the ambiguity of the SCR before a dismabiguating word. For example, “Alisha was the one handed the chair” is ambiguous for an AAL speaker between a SCR and a reduced relative clause, as discussed above. The presence of a preposition such as “to” or “by” disambiguates as it indicates if Alisha is receiving or giving the chair. With this design I test both AAL and MAE speakers. Special focus is given to the MAE speaking participants as the SCR is not present in their dialect. Using the Noisy Channel Model proposed by Levy (2008), I explore how these speakers comprehend a unfamiliar, ungrammatical, and “noisy” structure. The results suggest that MAE comprehenders prefer the rare parse, the reduced relative, over the “noisy” and ungrammatical option, the SCR. This is an interesting result as it contrasts with similar work done by Keshev and Meltzer-Asscher (2021) and their work on Hebrew. I conclude with a discussion surrounding how the incorporation of dialects can further inform linguistic study surrounding the Noisy Channel model, as well as ensure a more diverse representation of languages and dialects in the literature. The key contributions of this dissertation are as follows: (i) it establishes the distribution of SCRs in an AAL speaking community, (ii) finds that off-the-shelf predictive language models can exhibit behavior that would allow for the presence of an SCR, but it does so inconsistently and at a low likelihood, and (iii) finds that MAE comprehenders prefer the uncommon reduced relative parse over the subject contact relative, following a Rare over Noisy pattern.