Quantity-related variation of duration, pitch and vowel quality in spontaneous Estonian

The three-way distinction of the Estonian quantity is a feature of the primary stressed disyllabic foot. The quantity degrees are realized by different temporal patterns of the segments within the foot. Additionally, other phonetic features appear to vary depending on the quantity, such as pitch contour and vowel quality. In this paper, the quantity-related variation of segment duration, pitch, and vowel quality was investigated in spontaneous Estonian in words occurring in sentence-medial position. While a disyllabic foot can be made up of a number of segmental combinations, the data showed that the quantity opposition operates independently of the segmental structure of the foot. The effect of the analyzed features was evaluated with a multinomial logistic regression model. The model showed that all the variables which were included had a significant effect. Besides the inverse relation of the stressed and unstressed syllable rhymes, which is traditionally used to describe the three-way opposition, syllable onset duration also had a weak effect. Additionally, vowel quality was significant for the opposition of short (Q1) and long (Q2), and pitch alignment was significant for the opposition of long (Q2) and overlong (Q3) quantities.