Timothy J. O'Donnell

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Parallel computers have matured to the point where they are capable of running a significant production workload. Characterizing this workload, however, is far more complicated than for the single-processor case. Besides the varying number of processors that may be invoked, the nodes themselves may provide differing computational resources (memory size, for(More)
We present a model of unsupervised phonological lexicon discovery—the problem of simultaneously learning phoneme-like and word-like units from acoustic input. Our model builds on earlier models of unsupervised phone-like unit discovery from acoustic data (Lee and Glass, 2012), and unsupervised symbolic lexicon discovery using the Adaptor Grammar framework(More)
Understanding developmental and evolutionary aspects of the language faculty requires comparing adult languages users' abilities with those of non-verbal subjects, such as babies and non-human animals. Classically, comparative work in this area has relied on the rich theoretical frameworks developed by linguists in the generative grammar tradition. However,(More)
Activation of thin filaments in striated muscle occurs when tropomyosin exposes myosin binding sites on actin either through calcium-troponin (Ca-Tn) binding or by actin-myosin (A-M) strong binding. However, the extent to which these binding events contributes to thin filament activation remains unclear. Here we propose a simple analytical model in which(More)
In morphology, researchers have provided compelling evidence for the storage of even fully compositional structures that could otherwise be computed by rule. For example, a high-frequency word composed of multiple morphemes (e.g., root + plural inflection) may be stored directly rather than computed on the fly (e.g., Baayen, Dijkstra, & Schreuder, 1997).(More)
This technical report presents a general framework for parsing a variety of grammar formalisms. We develop a grammar formalism, called an Abstract Grammar, which is general enough to represent grammars at many levels of the hierarchy, including Context Free Grammars, Minimalist Grammars, and Generalized Context-free Grammars. We then develop a single(More)
We present a model for inducing sentential argument structure, which distinguishes arguments from optional modifiers. We use this model to study whether representing an argument/modifier distinction helps in learning argument structure, and whether a linguistically-natural argument/modifier distinction can be induced from distributional data alone. Our(More)
The 1994 Molecular Graphics Art Show and Video Show were presented at the 13th annual international meeting of the Molecular Graphics and Modelling Society. The art show--shown in the Mary & Leigh Block Gallery on the campus of Northwestern University, Evanston, Illinois--included original artworks by eighteen artists and the video show included nine(More)
a r t i c l e i n f o Low male voice pitch may communicate potential benefits for offspring in the form of heritable health and/or dominance, whereas access to resources may be indicated by correlates of socioeconomic status, such as sociolinguistic features. Here, we examine if voice pitch and social dialect influence women's perceptions of men's(More)