The standard ParsEval metrics alone are often not sufficient for evaluating parsers integrated in natural language understanding systems. We propose to augment intrinsic parser evaluations by extrinsic measures in the context of human-robot interaction using a corpus from a human cooperative search task. We compare a constituent with a dependency parser on both intrinsic and extrinsic measures ...

This lecture note describes an iterative optimization algorithm, ‘SALSA’, for solving L1-norm penalized least squares problems. We describe the use of SALSA for sparse signal representation and approximation, especially with overcomplete Parseval transforms. We also illustrate the use of SALSA to perform basis pursuit (BP), basis pursuit denoising (BPD), and morphological component analysis (MC...

Fourier Integral Operators appear naturally in a variety of problems related to hyperbolic partial differential equations. While wavelets and other traditional time-frequency methods have been successfully employed for representing many classes of singular integral operators, these methods are not equally effective in dealing with Fourier Integral Operators. In this paper, we show that the shea...

This paper presents a statistical parser for a wide-coverage Combinatory Categorial Grammar (CCG) derived from the Penn Treebank. The Treebank is translated to a corpus of canonical CCG derivations. We de ne a generative statistical model over CCG derivations and train it on the transformed Treebank. This model is evaluated using Parseval measures and the accuracy of recovery of word-word depen...

This paper considers group reconstruction systems (GRS’s), for finite dimensional real or complex Hilbert spaces H, that are associated with unitary representations of finite abelian groups. The relation between these GRS’s and the generalized Fourier matrix is established. A special type of Parseval GRS, called harmonic reconstruction system (HRS), is defined. It is shown that there exist HRS’...

This paper introduces a new Parseval frame, based on the 3–D shearlet representation, which is especially designed to capture geometric features such as discontinuous boundaries with very high efficiency. We show that this approach exhibits essentially optimal approximation properties for 3–D functions f which are smooth away from discontinuities along C2 surfaces. In fact, the N term approxima...

Segmentation plays an important role in many preprocessing stages in image processing. Recently, convex relaxation methods for image multi-labeling were proposed in the literature. Often these models involve the total variation (TV) semi-norm as regularizing term. However, it is well-known that the TV functional is not optimal for the segmentation of textured regions. In recent years directiona...

Traditional methods of time-frequency and multiscale analysis, such as wavelets and Gabor frames, have been successfully employed for representing most classes of pseudodifferential operators. However these methods are not equally effective in dealing with Fourier Integral Operators in general. In this paper, we show that the shearlets, recently introduced by the authors and their collaborators...

Partialsummen M = µ∈I M ψ µ ψ µ approximieren, wobei I M die Indexmenge der M größten Koeffizienten | ψ µ | ist. Verwenden wir hinreichend glatte Tensorprodukt-Wavelets, so besitzt der Approximationsfehler M der besten M-Term-Approximation M das optimale, asymptotische Abklingverhalten der Ordnung Für stückweise C 2-Bilder liefern die Curvelets gemäß [CD04] die Approximationseigenschaft M = − M...

This paper describes use of negative examples in training the HVS semantic model. We present a novel initialization of the lexical model using negative examples extracted automatically from a semantic corpus as well as description of an algorithm for extraction these examples. We evaluated the use of negative examples on a closed domain human-human train timetable dialogue corpus. We significan...