Search Results - "DEMETRIOU, I. C"

Separation theorems for the extrema of best piecewise monotonic approximations to successive data by Demetriou, I. C.

“…Separation properties of the local extrema of best piecewise monotonic approximations to measurements of a real univariate function are of fundamental…”
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L2CXCV: A Fortran 77 package for least squares convex/concave data smoothing by Demetriou, I.C.

“…Fortran 77 software is given for least squares smoothing to data values contaminated by random errors subject to one sign change in the second divided…”
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Signs of divided differences yield least squares data fitting with constrained monotonicity or convexity by Demetriou, I.C.

“…Methods are presented for least squares data smoothing by using the signs of divided differences of the smoothed values. Professor M.J.D. Powell initiated the…”
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Least Squares Convex-Concave Data Smoothing by Demetriou, I C

“…We consider n noisy measurements of a smooth (unknown) function, which suggest that the graph of the function consists of one convex and one concave section…”
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A theorem for piecewise convex–concave data approximation by Demetriou, I.C.

“…We are given univariate data that include random errors. We consider the problem of calculating a best approximation to the data by minimizing a strictly…”
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A linearly distributed lag estimator with r -convex coefficients by Vassiliou, E.E., Demetriou, I.C.

“…The purpose of linearly distributed lag models is to estimate, from time series data, values of the dependent variable by incorporating prior information of…”
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Certain positive definite submatrices that arise from binomial coefficient matrices by Demetriou, I.C., Lipitakis, E.A.

“…We are concerned with the solution of an overdetermined system of compatible linear equations whose matrix arises from binomial coefficients with alternating…”
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CXFTV2: A Fortran subroutine for the discrete least squares convex approximation by Demetriou, I.C.

“…A Fortan subroutine calculates the least squares approximation to n data values containing random errors subject to non-negative second divided differences…”
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A O(n) algorithm for the discrete best L4 monotonic approximation problem by Demetriou, I.C.

“…An approximation to discrete noisy data is constructed that obtains monotonicity. Precisely, we address the problem of making the least sum of 4th powers…”
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An adaptive algorithm for least squares piecewise monotonic data fitting by Vassiliou, E., Demetriou, I.C.

“…The number of peaks and troughs of measurements of smooth function values can be unacceptably larger than the number of turning points of the function, when…”
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Discrete Piecewise Monotonic Approximation by a Strictly Convex Distance Function by Demetriou, I. C.

“…Theory and algorithms are presented for the following smoothing problem. We are given n measurements of a real-valued function that have been altered by random…”
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Adaptive Preconditioned Variational Methods For Solving Self-Adjoint Partial Differential Equations by Demetriou, I. C., Evans, D. J.

“…The implementation of the Preconditioned Conjugate Gradient method for the solution of large linear systems arising from the discretization of differential…”
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A Characterization Theorem for the Discrete Best Monotonic Approximation Problem by Demetriou, I. C.

“…A characterization theorem is derived that motivates a procedure for generating discrete best monotonic approximations to $n$ sequential data values, when a…”
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A linearly distributed lag estimator with r-convex coefficients: The Fifth Special Issue on Computational Econometrics by VASSILIOU, E. E, DEMETRIOU, I. C

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L1PMA: A Fortran 77 package for best Ld1 piecewise monotonic data smoothing by Demetriou, I C

“…Fortran 77 software is presented for the calculation of a best Ld1 approximation to n measurements that include random errors by requiring k-1 sign changes in…”
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An adaptive algorithm for least squares piecewise monotonic data fitting: Computational econometrics by VASSILIOU, E, DEMETRIOU, I. C

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L1PMA: A Fortran 77 package for best L1 piecewise monotonic data smoothing by Demetriou, I.C

“…Fortran 77 software is presented for the calculation of a best L 1 approximation to n measurements that include random errors by requiring k−1 sign changes in…”
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A theorem for piecewise convex-concave data approximation by DEMETRIOU, I. C

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