Linda Kaufman

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A new regression technique based on Vapnik’s concept of support vectors is introduced. We compare support vector regression (SVR) with a committee regression technique (bagging) based on regression trees and ridge regression done in feature space. On the basis of these experiments, it is expected that SVR will have advantages in high dimensionality space(More)
The EM algorithm is the basic approach used to maximize the log likelihood objective function for the reconstruction problem in positron emission tomography (PET). The EM algorithm is a scaled steepest ascent algorithm that elegantly handles the nonnegativity constraints of the problem. It is shown that the same scaled steepest descent algorithm can be(More)
In this paper we explain some of the changes that have been incorporated in the latest version of the LAPACK subroutine for reducing a symmetric banded matrix to tridiagonal form. These modifications improve the performance for larger-bandwidth problems and reduce the number of operations when accumulating the transformations onto the identity matrix, by(More)
This paper persents a program SERRG2 that solves separable elliptic equations on a rectangle. The program uses a matrix decomposition technique to directly solve the linear system arising from a Rayleigh-Ritz-Galerkin approach with tensor product B-splines to solve the separable partial differential equation. This approach permits high-order(More)
Most algorithms associated with finding eigenvalues of banded matrices do not have many, if any, obvious vector operations. On vector machines it is not immediately obvious, if sufficient memory is available, whether one should treat banded matrices as dense matrices and use algorithms that have vector operations, or take advantage of the band structure of(More)
The QZ algorithm of Moler and Stewart solves the generalized eigenvalue problem of finding and x such that Ax = XBx for real square matrices A and B by first simultaneously reducing A to upper Hessenberg form and B to triangular form and then iteratively reducing A to quasi-triangular form (no two consecutive elements on the subdiagonal of A are(More)
The incidence of hepatocellular carcinoma (HCC) is significantly elevated in a Hispanic community in Bexar County, Texas. Chronic exposure to dietary aflatoxins (AFs) is a major risk factor for HCC; increased risk has been linked to polycyclic aromatic hydrocarbon (PAH) co-exposure and hepatitis virus infection. The aims of this study were to assess AF and(More)