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FREQUENCY DISTRIBUTIONS
"... A method of performing automatic classification of positive timefrequency distributions is presented. These distributions are computed via constrained optimization, minimizing the crossentropy of the distribution subject to a set of constraints. An algorithm for clustering using crossentropy as t ..."
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A method of performing automatic classification of positive timefrequency distributions is presented. These distributions are computed via constrained optimization, minimizing the crossentropy of the distribution subject to a set of constraints. An algorithm for clustering using cross
Distributional Clustering Of English Words
 In Proceedings of the 31st Annual Meeting of the Association for Computational Linguistics
, 1993
"... We describe and evaluate experimentally a method for clustering words according to their dis tribution in particular syntactic contexts. Words are represented by the relative frequency distributions of contexts in which they appear, and relative entropy between those distributions is used as the si ..."
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Cited by 629 (27 self)
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We describe and evaluate experimentally a method for clustering words according to their dis tribution in particular syntactic contexts. Words are represented by the relative frequency distributions of contexts in which they appear, and relative entropy between those distributions is used
Matching pursuits with timefrequency dictionaries
 IEEE Transactions on Signal Processing
, 1993
"... AbstractWe introduce an algorithm, called matching pursuit, that decomposes any signal into a linear expansion of waveforms that are selected from a redundant dictionary of functions. These waveforms are chosen in order to best match the signal structures. Matching pursuits are general procedures t ..."
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Cited by 1671 (13 self)
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to compute adaptive signal representations. With a dictionary of Gabor functions a matching pursuit defines an adaptive timefrequency transform. We derive a signal energy distribution in the timefrequency plane, which does not include interference terms, unlike Wigner and Cohen class distributions. A
TimeFrequency Distributions—a Review
 Proceedings of the IEEE, 77
, 1989
"... A review and tutorial of the fundamental ideas and methods of joint timefrequency distributions is presented. The objective of the field is to describe how the spectral content of a signal is changing in time, and to develop the physical and mathematical ideas needed to understand what a timevaryi ..."
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Cited by 135 (1 self)
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A review and tutorial of the fundamental ideas and methods of joint timefrequency distributions is presented. The objective of the field is to describe how the spectral content of a signal is changing in time, and to develop the physical and mathematical ideas needed to understand what a time
Optimization Flow Control, I: Basic Algorithm and Convergence
 IEEE/ACM TRANSACTIONS ON NETWORKING
, 1999
"... We propose an optimization approach to flow control where the objective is to maximize the aggregate source utility over their transmission rates. We view network links and sources as processors of a distributed computation system to solve the dual problem using gradient projection algorithm. In thi ..."
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Cited by 694 (64 self)
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at different times and with different frequencies. We provide asynchronous distributed algorithms and prove their convergence in a static environment. We present measurements obtained from a preliminary prototype to illustrate the convergence of the algorithm in a slowly timevarying environment.
Modeling and Forecasting Realized Volatility
, 2002
"... this paper is built. First, although raw returns are clearly leptokurtic, returns standardized by realized volatilities are approximately Gaussian. Second, although the distributions of realized volatilities are clearly rightskewed, the distributions of the logarithms of realized volatilities are a ..."
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Cited by 549 (50 self)
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within a standard frictionless arbitragefree multivariate pricing environment. In section 3 we discuss the practical construction of realized volatilities from highfrequency foreign exchange returns. Next, in section 4 we summarize the salient distributional features of r...
Relations between the statistics of natural images and the response properties of cortical cells
 J. Opt. Soc. Am. A
, 1987
"... The relative efficiency of any particular imagecoding scheme should be defined only in relation to the class of images that the code is likely to encounter. To understand the representation of images by the mammalian visual system, it might therefore be useful to consider the statistics of images f ..."
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Cited by 831 (18 self)
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of space, spatial frequency, and orientation (Gaborlike transforms). For many classes of image, such codes will not be an efficient means of representing information. However, the results obtained with six natural images suggest that the orientation and the spatialfrequency tuning of mammalian simple
Evaluation of Release Consistent Software Distributed Shared Memory on Emerging Network Technology
"... We evaluate the effect of processor speed, network characteristics, and software overhead on the performance of releaseconsistent software distributed shared memory. We examine five different protocols for implementing release consistency: eager update, eager invalidate, lazy update, lazy invalidat ..."
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Cited by 467 (43 self)
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We evaluate the effect of processor speed, network characteristics, and software overhead on the performance of releaseconsistent software distributed shared memory. We examine five different protocols for implementing release consistency: eager update, eager invalidate, lazy update, lazy
A ReExamination of Text Categorization Methods
, 1999
"... This paper reports a controlled study with statistical significance tests on five text categorization methods: the Support Vector Machines (SVM), a kNearest Neighbor (kNN) classifier, a neural network (NNet) approach, the Linear Leastsquares Fit (LLSF) mapping and a NaiveBayes (NB) classifier. We f ..."
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Cited by 853 (24 self)
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focus on the robustness of these methods in dealing with a skewed category distribution, and their performance as function of the trainingset category frequency. Our results show that SVM, kNN and LLSF significantly outperform NNet and NB when the number of positive training instances per category
The Frequency Distribution Of English Syntagms
, 1973
"... this paper, a methodology is outlined by which the frequency usage of syntactic structures can be measured for subsets of a language, and for a language as a whole. In order to establish homogeneity features within a subset, reliance is made on calculations of chisquare on batches of sentences withi ..."
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Cited by 1 (0 self)
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within the subset. ]Before considering whether or not a more sensitive test should be applied to detect significant differences within and among subsets of a language, it seemed advisable to determine the frequency distribution of syntagms throughout particular genres. An extension of the methodology
Results 1  10
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