We apply a complexity theoretic notion of feasible learnability called "polynomial learnability" to the evaluation of grammatical formalisms for linguistic description. We show that a novel, nontrivial constraint on the degree of "locality" of grammars allows not only context free languages but also a rich class of mildly context sensitive languages to be polynomially learnable. We discuss poss...

We propose to apply a complexity theoretic notion of feasible learnability called "polynomial learnability" to the evaluation of grammatical formalisms for linguistic description. Polynomial learnability was originally defined by Valiant in the context of boolean concept learning and subsequently generalized by Blumer et al. to infinitary domains. We give a clear, intuitive exposition of this n...

We consider random Schrödinger equations on Rd for d ≥ 3 with a homogeneous Anderson-Poisson type random potential. Denote by λ the coupling constant and ψt the solution with initial data ψ0. The space and time variables scale as x ∼ λ−2−κ/2, t ∼ λ−2−κ with 0 < κ < κ0(d). We prove that, in the limit λ → 0, the expectation of the Wigner distribution of ψt converges weakly to the solution of a he...

In Logic Programming, ”negation as failure” has become an important area of research. ”Negation as failure” is ubiquitous in deductive databases ([Minker, 1987]), in truth maintenance systems ([Doyle, 1979]), and in default logic ([Reiter, 1980]). It is a naturally occurring “non-monotonic logic”. The original (breadth-first) PROLOG is a (monotonic) classical logic of pure Horn clauses. There, ...

OBJECTIVE The aim of this study was to investigate whether volumes of the corpus callosum could predict a response to antiepileptic drugs in patients with newly diagnosed focal epilepsy. METHODS Fifty-three patients with newly diagnosed focal epilepsy of unknown etiology and healthy subjects were enrolled in this study. First, we analyzed the differences in the volumes of the corpus callosum ...

Locking mechanisms and metal-liner interface surfaces of six modular acetabular systems were evaluated to determine their effect on micromotion and backside wear of the polyethylene liner. Rotational and axial motion between the metal shell and polyethylene liner was measured in the Duraloc (DePuy, Warsaw, IN), Harris-Galante (Zimmer, Warsaw, IN), Impact (Biomet, Warsaw, IN), Lip Loc (Biomet), ...

We prove the existence of localized states at the edges of the bands for the two-dimensional Landau Hamiltonian with a random potential, of arbitrary disorder, provided that the magnetic field is sufficiently large. The corresponding eigenfunctions decay exponentially with the magnetic field and distance. We also prove that the integrated density of states is Lipschitz continuous away from the ...

A growing body of literature supports the association between adverse stress experiences and health inequities, including obesity, among African American/Black women. Adverse stress experiences can contribute to poor appetite regulation, increased food intake, emotional eating, binge eating, and sedentary behavior, all of which can contribute to weight gain and obesity. Most research studies co...

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