Consider applying the Conjugate Residual (CR) method, which is a Krylov subspace type iterative solver, to systems of linear equations Ax = b or least squares problems min x∈Rn ‖b −Ax‖2, where A is singular and nonsymmetric. We will show that when R(A)⊥ = kerA, the CR method can be decomposed into the R(A) and kerA components, and the necessary and sufficient condition for the CR method to conv...

The present paper discusses the problem of least-squares over the real symplectic group of matrices Sp(2n,R). The least-squares problem may be extended from flat spaces to curved spaces by the notion of geodesic distance. The resulting non-linear minimization problem on manifold may be tackled by means of a gradient-descent algorithm tailored to the geometry of the space at hand. In turn, gradi...

This paper investigates interval pseudo-inverse matrices. We state an Interval Greville algorithm and extensions with bisections for calculation of interval pseudo-inverse matrices and give the examples of interval pseudo-inversion application for estimation of solutions of systems of linear equations, and show applications for estimations of solutions and pseudo-solutions in a least squares se...

Erdős and Rényi proposed in 1960 a probabilistic model for sums of s integral sth powers. Their model leads almost surely to a positive density for sums of s pseudo sth powers, which does not reflect the case of sums of two squares. We refine their model by adding arithmetical considerations and show that our model is in accordance with a zero density for sums of two pseudo-squares and a positi...

Source Localization in the non-synchronous mobile system is a very important issue since it only requires synchronized clocks between the based stations (BSs) and can reduce system complexity. There are time-difference-of-arrival (TDOA) and pseudo-range time-of-arrival (TOA) based localization techniques for a non-synchronous mobile system. Although many methods and performance analysis have be...

Hedonic methods are a prominent approach in the construction of quality-adjusted price indexes. This paper shows that the process of computing such indexes is substantially simplified if arithmetic (geometric) price indexes are computed based on exponential (log-linear) hedonic functions estimated by the Poisson pseudo maximum likelihood (ordinary least squares) method. A Monte Carlo simulation...

two multivariate calibration methods are compared for the simultaneous chromatographic determination and separation of sulfamethoxazole (smx) and phthalazine (phz) by high performance liquid chromatography (hplc). multivariate calibration techniques such as classical least squares (cls) and inverse least squares (ils) were introduced into hplc to determine the quantification by using uv detecto...