A Review of Corpus-based Statistical Models of Language Variation

This paper is a brief review of the research on language variation using corpus data and statistical modeling methods. The variation phenomena covered in this review include phonetic variation (in spontaneous speech) and syntactic variation, with a focus on studies of English and Chinese. The goal of this paper is to demonstrate the use of corpus-driven statistical models in the study of language variation, and discuss the contribution and future directions of this line of research.

Sonority bias in Rugao di-syllabic syllable contraction

Two analyses, vowel sonority and the linear order of pre-contraction vowels, have been proposed to account for the vowel selection between two competing vowels in Chinese syllable contraction. An experiment was run to test whether sonority and/or linear order bias the vowel selection in Rugao syllable contraction. Our results confirmed the role of vowel sonority, and did not present supporting evidence for the linear order analysis. Sonority hierarchies along the dimensions of both height and centrality exhibit the same consistent and robust pattern, providing a new perspective to look at competing vowels in vowel-related phonological processes

Frequency Effects in Second Language Acquisition: An Annotated Survey

The aim of this study is to investigate the relationship between frequency and language acquisition from many perspectives including implicit and explicit instruction, frequency effects on morpheme acquisition in L2, the relationship between frequency and multi-word constructions, frequency effects on phonetics, vocabulary, gerund and infinitive constructions, bitransitive constructions, and so on. In his impressive article on frequency, Ellis (2002a) asked this crucial question about the relationship between frequency and SLA: “How exactly does the frequency of patterns in the input affect acquisition?” Another fundamental question that needs to be answered is: “What purpose does frequency serve in language acquisition?” In addition, frequency and range are said to be the most salient criteria for determining the general usefulness of a word (Koprowski, 2005). Moreover, both corpus and experimental data suggest that frequency has significant effects on second language acquisition. These questions and arguments, which constitute the foundation of frequency studies in second language acquisition, led and guided this study. This annotated survey, summarizing the studies on frequency effects on L2 learning, shows that there are still lots of ways to go with research on the relationship between frequency and second language acquisition in the literature. Some pedagogical implications are discussed with recommendations for the stakeholders of foreign language contexts (i.e. curriculum designers, coursebook writers, language teachers and learners)

Lexical Effects in Phonemic Neutralization in Taiwan Mandarin

BLS 38: General Session and Thematic Session on Language Contac

Mechanism of disyllabic tonal reduction in Taiwan Mandarin

This study was designed to test the hypothesis that time pressure is a direct cause of tonal reduction in Taiwan Mandarin. Tonal reduction refers to the phenomenon of the tones of a disyllabic unit being contracted into a monosyllabic unit. An experiment was carried out in which six native Taiwan Mandarin male speakers produced sentences containing disyllabic compound words /ma/+/ma/ with varying tonal combinations at different speech rates. Analyses indicated that increasing time pressure led to severe tonal reductions. Articulatory effort, measured by the slope of F0 peak velocity of unidirectional movement over F0 movement amplitude, is insufficient to compensate for duration-dependent undershoot (in particular, when time pressure exceeds certain thresholds). Mechanisms of tonal reduction were further examined by comparing F0 velocity profiles against the Edge-in model, a rule-based phonological model. Results showed that the residual tonal variants in contracted syllables are gradient rather than categorical—as duration is shortened, the movement towards the desired targets is gradually curtailed

Mechanism of extreme phonetic reduction: evidence from Taiwan Mandarin

Extreme reduction refers to the phenomenon where intervocalic consonants are so severely reduced that two or more adjacent syllables appear to be merged into one. Such severe reduction is often considered a characteristic of natural speech and to be closely related to factors including lexical frequency, information load, social context and speaking style. This thesis takes a novel approach to investigating this phenomenon by testing the time pressure account of phonetic reduction, according to which time pressure is the direct cause of extreme reduction. The investigation was done with data from Taiwan Mandarin, a language where extreme reduction (referred to as contraction) has been reported to frequently occur. Three studies were conducted to test the main hypothesis. In Study 1, native Taiwan Mandarin speakers produced sentences containing nonsense disyllabic words with varying phonetic structures at differing speech rates. Spectral analysis showed that extreme reduction occurred frequently in nonsense words produced under high time pressure. In Study 2a, further examination of formant peak velocity as a function of formant movement amplitude in experimental data suggested that articulatory effort was not decreased during reduction, but in fact likely to be increased. Study 2b examined high frequency words from three spontaneous speech corpora for reduction variations. Results demonstrate that patterns of reduction in high frequency words in spontaneous speech (Study 2b) were similar to those in nonsense words spoken under experimental conditions (Study 2a). Study 3 investigated tonal reduction with varying tonal contexts and found that tonal reduction can also be explained in terms of time pressure. Analysis of F0 trajectories demonstrates that speakers attempt to reach the original underlying tonal targets even in the case of extreme reduction and that there was no weakening of articulatory effort despite the severe reduction. To further test the main hypothesis, two computational modelling experiments were conducted. The first applied the quantitative Target Approximation model (qTA) for tone and intonation and the second applied the Functional Linear Model (FLM). Results showed that severely reduced F0 trajectories in tone dyads can be regenerated to a high accuracy by qTA using generalized canonical tonal targets with only the syllable duration modified. Additionally, it was shown that using FLM and adjusting duration alone can give a fairly good representation of contracted F0 trajectory shapes. In summary, results suggest that target undershoot under time pressure is likely to be the direct mechanism of extreme reduction, and factors that have been commonly associated with reduction in previous research very likely have an impact on duration, which in turn determines the degree of target attainment through the time pressure mechanism