Abstract: | This paper presents a set of simple statistical measures that illustrate the difference
between native English speakers and Polish learners of English in varying the length of
vocalic segments in read speech. Relative vowel duration and vowel length variation are
widely used as basic criteria for establishing rhythmic differences between languages and
dialects of a language. The parameter of vocalic duration is employed in popular measures
such as ΔV (Ramus et al. 1999), VarcoV (Dellwo 2006, White and Mattys 2007), and PVI
(Low et al. 2000, Grabe and Low 2002). Apart from rhythm studies, the processing of
data concerning vowel duration can be used to establish the level of discrepancy between
native speech and learner speech in investigating other temporal aspects of FL
pronunciation, such as tense-lax vowel distinction, accentual lengthening or the degree of
unstressed vowel reduction, which are often pointed out as serious problems in the
acquisition of English pronunciation by Polish learners. Using descriptive statistics
(relations between personal mean vowel duration and standard deviation), the author
calculates several indices that demonstrate individual learners' (13 subjects) scores in
relation to the native speakers' (12 subjects) score ranges. In some tested aspects, the
results of the two groups of speakers are almost cleanly separated, which suggests not
only the existence of specific didactic problems but also their actual scale. |