I demonstrate the application of hierarchical regression modeling, a state-of-the-art technique for statistical inference, to language research. First, a stable sociolinguistic variable in Philadelphia (Labov, 2001) is reconsidered, with attention paid to the treatment of collinearities among socioeconomic predictors. I then demonstrate the use of hierarchical models to account for the random s...

Recently, various types of mixture models have been developed for data sets having a hierarchical or multilevel structure (see, e,g., [9, 12]). Most of these models include finite mixture distributions at multiple levels of a hierarchical structure. In these multilevel mixture models, selection of the number of mixture component is more complex than in standard mixture models because one has to...

Question answering systems answer correctly to different questions because they are based on different strategies. In order to increase the number of questions which can be answered by a single process, we propose solutions to combine two question answering systems, QAVAL and RITEL. QAVAL proceeds by selecting short passages, annotates them by question terms, and then extracts from them answers...

Technological advances in genotyping have given rise to hypothesisbased association studies of increasing scope. As a result, the scientific hypotheses addressed by these studies have become more complex and more difficult to address using existing analytic methodologies. Obstacles to analysis include inference in the face of multiple comparisons, complications arising from correlations among t...

Technological advances in genotyping have given rise to hypothesis-based association studies of increasing scope. As a result, the scientific hypotheses addressed by these studies have become more complex and more difficult to address using existing analytic methodologies. Obstacles to analysis include inference in the face of multiple comparisons, complications arising from correlations among ...

We present a model hierarchy multilevel optimisation approach to solve an optimal boundary control problem in glass manufacturing. The process is modelled by radiative heat transfer and formulated as an optimal control problem restricted by partial differential algebraic equations (PDAE) and additional control constraints. We consider a sequence of model approximations given by space-time depen...

We use simulation studies, whose design is realistic for educational and medical research (as well as other fields of inquiry), to compare Bayesian and likelihood-based methods for fitting variance-components (VC) and random-effects logistic regression (RELR) models. The likelihood (and approximate likelihood) approaches we examine are based on the methods most widely used in current applied mu...

This paper proposes a generalized space vector pulse width modulation (SVPWM) technique for hybrid multilevel inverters for minimizing total harmonic distortion (THD). The proposed method easily determines the actual location of the instantaneous reference space vector and the corresponding switching sequence of a multilevel inverter. The proposed algorithm offers a novel method for minimizing ...