Dissertation Defense: Irani

May 22, 2019 at - | Linguistics Department Seminar Room -- Room 326, 3401-C Walnut Street, Suite 300

Ava Irani will defend her dissertation, titled "Learning from Positive Evidence: The Acquisition of Verb Argument Structure," on Wednesday, May 22, 2019 at 10am. The defense is open to the public and will be held in the Linguistics Department Seminar Room (Room 326, 3401-C Walnut Street, Suite 300).

More information and the abstract can be found below. 

Dissertation supervisors: Julie Anne Legate and Charles Yang

Committee: Kathryn Schuler

Date and time: Wednesday, May 22, 2019 at 10am

Location: Room 326, 3401-C Walnut Street, Suite 300

Learning from Positive Evidence: The Acquisition of Verb Argument Structure 

This dissertation investigates how children acquire verb argument structure using positive evidence from the linguistic input. I discuss three case studies: the acquisition of raising and control verbs, the acquisition of causatives, and the acquisition of passives. I address previous theories that attempt to account for verb argument structure learning through indirect negative evidence (e.g., Pinker 1989), and I show that these approaches are inadequate in accounting for the developmental trajectory of the learner. Instead, I defend two learning models in my dissertation: the Sufficiency Principle (Yang 2016) and the Active Mapping Model of Language Acquisition. I propose the Active Mapping Model to illustrate how the learner uses conceptual and structural information in their language to form verb classes. This model does not assume an innate mapping between the conceptual and structural cues.

Chapter 2 discusses the acquisition of raising and control verbs. The literature has foregrounded a learnability problem regarding the acquisition of these of verbs (Becker 2006): if some verbs can be both raising and control, then what prevents the learner from assuming that all verbs can take either structure? Using the Sufficiency Principle, I show that the problem of overgeneralization does not arise.

In Chapter 3, I discuss the acquisition of the causative alternation rule, which is a true case of overgeneralization, as seen by the errors made by children in their production data. I demonstrate that the overgeneralization errors are predicted under the Active Mapping Model where the learner categorizes verbs into classes based on conceptual and structural cues. Given the learner's vocabulary size and verb classes, the causative alternation rule is found to be productive according to the Sufficiency Principle when the learner’s input is examined.

In Chapter 4, I use the Sufficiency Principle and the Active Mapping Model to examine the developmental trajectory of children's acquisition of passives. Using the child production data and the input data, I show that the passive construction is productive in the input, and productive for the English-learning child. Moreover, under the Active Mapping Model, I show that the asymmetry between the acquisition of actional and non-actional passives observed in the literature (e.g., Pinker et al. 1987) is predicted. In each of the cases discussed in the chapters of the dissertation, I demonstrate the role of the input in language acquisition.