Automated assessment using Natural Language Processing (NLP) has the potential to make English speaking assessments more reliable, authentic, and accessible. Yet without careful examination, NLP may exacerbate social prejudices based on gender or native language (L1). Current NLP-based assessments are prone to such biases, yet research and…

This study examined how L2 English speakers interpreted the notion of native English speakers (NESs) and nonnative English speakers (NNESs) and whether nativeness would influence their self-perception and speech production. It aimed at filling the following research gaps. First, limited studies have explored how L2 English speakers view the other…

Nonverbal behavior is essential in human interaction (Gullberg, de Bot, & Volterra, 2008; McNeill, 1992, 2005). For second language speakers, nonverbal features can be helpful for successful and efficient communication (e.g., Dahl & Ludvigsen, 2014). However, due to the complexity of nonverbal features, language testing institutions have…

Despite the importance that learners must place on using prosody appropriately in EIL interaction, pragmatic functions of prosody have been largely disregarded in teaching materials and classroom instruction (Nikolic, 2018). Moreover, with a recent change in classroom paradigms instigated by the global development of educational technologies and…

This dissertation explored whether unnecessary linguistic complexity (LC) in mathematics and biology assessment items changes the direction and significance of differential item functioning (DIF) between subgroups emergent bilinguals (EBs) and English proficient students (EPs). Due to inconsistencies in measuring LC in items, Study One adapted a…

Despite the benefits of performance-based oral communication tests, a plethora of variables, as illustrated in Ockey and Li's (2015) model of oral communication assessment, can create construct-irrelevant variance in test scores. In relation to human participants in the oral communication tests, previous studies mostly focused on the direct effect…

Syntactic (i.e., grammatical) complexity refers to the range and the degree of sophistication of the forms that appear in language production (Ortega, 2003). This concept has long been regarded as an important construct of language proficiency and has been actively investigated in the field of second language (L2) writing. Syntactic complexity is…

A fundamental issue in speech science concerns the extent to which speech sounds are mentally represented by articulatory-motor and/or auditory-acoustic features. This dissertation aims to expand upon the current literature by investigating changes in production and perception following visual feedback training with either articulatory or acoustic…

This study investigated a computer-assisted pronunciation training (CAPT) software that utilized automatic speech recognition (ASR) and accent conversion technology to improve pronunciation of second language learners. Such speech processing method is capable of addressing the typical shortcoming of ASR technology for second language pronunciation…

Rater variation in performance assessment can impact test-takers' scores and compromise assessments' fairness and validity (Crooks, Kane, & Cohen, 1996). Rater variation can also undermine a test's validity and fairness; therefore, it is important to investigate raters' scoring patterns in order to inform rater training. Substantial work has…

Understanding the sources of variance in speaking assessment is important in Japan where society's high demand for English speaking skills is growing. Three challenges threaten fair assessment of speaking. First, in Japanese university speaking courses, teachers are typically the only raters, but teachers' knowledge of their students may unfairly…

Speaking performance tests typically employ raters to produce scores; accordingly, variability in raters' scoring decisions has important consequences for test reliability and validity. One such source of variability is the rater's level of expertise in scoring. Therefore, it is important to understand how raters' performance is influenced by…

Second language (L2) oral performance assessment always involves raters' subjective judgments and is thus subject to rater variability. The variability due to rater characteristics has important consequential impacts on decision-making processes, particularly in high-stakes testing situations (Bachman, Lynch, & Mason, 1995; A. Brown, 1995;…

By centralizing the issue of test fairness in language proficiency assessments, this study responds to a call by researchers for developing greater social responsibility in the language testing agenda. As inquiries into language attitude and psychology indicate, there is an underlying uncertainty pertaining to the validity of test use and score…

This study of L-2 Russian interlanguage production examined the salience of phonetic, lexical and syntactical features for L-1 listener intelligibility, based on L-2 recitation of written scripts (Part I) and also unrehearsed speech (Part II). Part III of the study investigated strategies used by native-speaking teachers of Russian as a Second…