Introduction and notation. The sensitivity of computational problems is a major factor determining the accuracy of computations in machine arithmetic. It may be revealed and taken into account by the methods of perturbation analysis [14, 6]. Below we consider the technique of Lyapunov majorants for perturbation analysis of algebraic matrix equations F (A, X) = 0 arising in science and engineeri...

In this paper we discuss identification of codependent VAR and VEC models. Codependence of order q is given if a linear combination of autocorrelated variables eliminates the serial correlation after q lags. Importantly, maximum likelihood estimation and corresponding likelihood ratio testing are only possible if the codependence restrictions can be uniquely imposed. However, our study reveals ...

We present a unified approach to quantum error correction, called operator quantum error correction. Our scheme relies on a generalized notion of a noiseless subsystem that is investigated here. By combining the active error correction with this generalized noiseless subsystems method, we arrive at a unified approach which incorporates the known techniques--i.e., the standard error correction m...

We implement several Bayesian and classical models to forecast employment for eight sectors of the US economy. In addition to standard vector-autoregressive and Bayesian vector autoregressive models, we also include the information content of 143 additional monthly series in some models. Several approaches exist for incorporating information from a large number of series. We consider two approa...

We describe the two-sided ideals in the universal enveloping algebras of the Lie algebras of vector fields on the line and the circle which annihilate the tensor density modules. Both of these Lie algebras contain the projective subalgebra, a copy of sl2. The restrictions of the tensor density modules to this subalgebra are duals of Verma modules (of sl2) for Vec(R) and principal series modules...

This study considered the impact of inflation on unemployment in Nigeria viz avis selected macroeconomic variables. The researcher adopted co integration, vector error correction model and VEC Granger causality test econometric procedure analysis data employed. specific objectives are; (i) to determine extent which within period study, (ii) examine if government expenditure have any significant...

In this paper, we always assume that H is an N-dimensional complex Hilbert space. Let L(H) be the set of all linear operators from H to H . A state ρ of some quantum system, described by H , is a positive semi-definite operator of trace one, in particular, for each unit vector |ψ〉 ∈ H , the operator ρ = |ψ〉〈ψ| is said to be a pure state. The set of all states onH is denoted by D(H). If X,Y ∈ L(...

globalization is a worldwide phenomenon. the concept globalization is a very recent term only establishing its current meaning in the 1970s, which emerged from the intersection of four inter related sets of communities of practice, academics, journalists, publishers. this paper models the channels through which globalization affects financial sector development in nigeria. to this end this stud...