Electronic Theses and Dissertations




Haiying Li



Date of Award


Document Type


Degree Name

Doctor of Philosophy




Experimental Psychology

Committee Chair

Arthur C. Graesser

Committee Member

Xiangen Hu

Committee Member

Philip Pavlik

Committee Member

Vasile Rus


The dissertation examined the impact of agents' conversational formality on the learning of summarization skills and learner impressions in an intelligent tutoring system (ITS) with trialogues (a teacher agent, a student agent, and a human learner). Formal language is in the informational genre (as opposed to narrative) and increases with word abstractness, syntactic complexity, referential cohesion, and deep cohesion. At the other end of the continuum, informal discourse tends to have concrete words, simple syntax, low cohesion (because knowledge-based inferences can fill the gaps), and high narrativity. There have been no experimental investigations that have maniputed teacher language because it is difficult and unreliable to have teachers systematically change their language in real world settings. This dissertation manipulates agents' communication language with three styles: (1) a formal condition in which both the teacher agent and the student agent spoke with a formal communication style, (2) an informal condition in which both agents spoke informally, and (3) a mixed condition in which the teacher agent spoke formally, whereas the student agent spoke informally. Unfortunately, results did not show significant effects of the formality manipulation on learning performance and learner impressions when adjusted with Bonferroni correction for 16 tests. A 90-min intervention that manipulated formality was not sufficient to have a significant impact on learning and summary writing, so the next step is to have an intervention that covers a longer period of time.


Data is provided by the student.

Library Comment

dissertation or thesis originally submitted to the local University of Memphis Electronic Theses & dissertation (ETD) Repository.