Melodic and rhythmic properties of speech correlate with grammatical structures such as phrase, and word boundaries. Listeners use prosodic information to identify syntactic units during speech perception. This processing can be characterized by a Fuzzy Logic Model of Perception (FLMP) (Massaro, 1987). Since FLMP models may be viewed within a logistic regression modeling framework (e.g., Crowther, Batchelder, & Hu, 1995), the current study used logistic regression models to investigate how the trading relationship between pitch and durational cues develops between children (ages 5 and 7) and adults. A listening experiment was conducted in which subjects interpreted word strings as "sun, flowerpot" or "sunflower, pot", depending on prosody. The audio stimuli for this two-alternative forced-choice task were created using re-synthesized speech having three levels of pitch and five levels of durational patterns. The data are being modeled as follows: Each level of pitch and durational will be treated as independent, binary variables. Pitch x Duration interactions and a constant will be assumed. Each possible combination of these terms will be tested against the obtained data. The best models for each age group will be selected based on the Generalized Akaike Information Criterion (GAIC; a generalization of AIC robust to model misspecification), as well as constraints concerning semantic interpretability and multicollinearity reduction. Age differences are predicted for the model structures and estimated coefficients. The results will be interpreted with respect to theories of cue-trading and a developmental cue-weighting shift in the use of prosodic cues for disambiguation. |