Articulatory Strategies for Place Contrasts of Unreleased Final Stops on Preceding Vowels: Evidence from Ultrasound Imaging

This ultrasound study examines the gestural coordination involved in vowel-to-consonant sequences concerning unreleased final stops, which are more susceptible to reduction than their released counterparts. Thus, coarticulatory information on the preceding vowel is important to signal place contrasts of post-vocalic stops. The gestural coordination of vowel-consonant sequences of monosyllabic words in Cantonese represents a testing case for having preserved phonemic contrasts of six unreleased final stops in a range of vowel contexts. Preliminary results from smoothing spline ANOVA and linear mixed-effect regression show that coarticulatory patterns depend on vowel height, that is, non-high vowels are undergoing gradual coarticulation whereas high vowels are phonologising the lingual properties of the unreleased final stops on the preceding vowels.

An asymptotic and empirical smoothing parameters selection method for smoothing spline ANOVA models in large samples

Summary Large samples are generated routinely from various sources. Classic statistical models, such as smoothing spline ANOVA models, are not well equipped to analyse such large samples because of high computational costs. In particular, the daunting computational cost of selecting smoothing parameters renders smoothing spline ANOVA models impractical. In this article, we develop an asympirical, i.e., asymptotic and empirical, smoothing parameters selection method for smoothing spline ANOVA models in large samples. The idea of our approach is to use asymptotic analysis to show that the optimal smoothing parameter is a polynomial function of the sample size and an unknown constant. The unknown constant is then estimated through empirical subsample extrapolation. The proposed method significantly reduces the computational burden of selecting smoothing parameters in high-dimensional and large samples. We show that smoothing parameters chosen by the proposed method tend to the optimal smoothing parameters that minimize a specific risk function. In addition, the estimator based on the proposed smoothing parameters achieves the optimal convergence rate. Extensive simulation studies demonstrate the numerical advantage of the proposed method over competing methods in terms of relative efficacy and running time. In an application to molecular dynamics data containing nearly one million observations, the proposed method has the best prediction performance.

Speakers’ rapidly-updated expectations influence prosodic realization of information structure

A production experiment was conducted to investigate the role of perspective-taking in the prosodic marking of information structure. Participants played an interactive game in which they produced verbal instructions that directed an addressee to place objects in locations on the computer screen. We manipulated (i) the participants’ assumptions about the addressee’s familiarity with the objects and (ii) the addressee’s accuracy in identifying the objects. F0 measurements of the participants’ utterances were analyzed with Smoothing-spline ANOVA models. We find that speakers’ expectations about the addressee’s knowledge state influence the prosodic realization of both new and given information, and that speakers rapidly update their expectations based on the addressee’s behavior during the conversation.

Backward multiple imputation estimation of the conditional lifetime expectancy function with application to censored human longevity data

The conditional lifetime expectancy function (LEF) is the expected lifetime of a subject given survival past a certain time point and the values of a set of explanatory variables. This function is attractive to researchers because it summarizes the entire residual life distribution and has an easy interpretation compared with the popularly used hazard function. In this paper, we propose a general framework of backward multiple imputation for estimating the conditional LEF and the variance of the estimator in the right-censoring setting. Simulation studies are conducted to investigate the empirical properties of the proposed estimator and the corresponding variance estimator. We demonstrate the method on the Beaver Dam Eye Study data, where the expected human lifetime is modeled with smoothing-spline ANOVA given the covariates information including sex, lifestyle factors, and disease variables.