I consider multivariate (vector) time series models in which the error covariance matrix may be time-varying. I derive a test of constancy of the error covariance matrix against the alternative that the covariance matrix changes over time. I design a new family of Lagrange-multiplier tests...

This paper contains a Lagrange multiplier test of the hypothesis that the covariance matrix of a multivariate time series model is constant over time. It is further assumed that under the alternative, the error variances are time-varying whereas the correlation remain constant over time. Under...

This paper studies a special class of vector smooth-transition autoregressive (VS- TAR) models containing common nonlinear features (CNFs). To test the existence of CNFs in a VSTAR model, a triangular representation for such a system containing CNFs is proposed. A procedure of testing CNFs in a...

This paper proposes a method for detecting the sources of misspecification in a dynamic stochastic general equilibrium (DSGE) model based on testing, in a data-rich environment, the exogeneity of the variables of the DSGE with respect to some auxiliary variables. Finding evidence of...

This paper proposes a method for detecting the sources of misspecification in a DSGE model based on testing, in a data-rich environment, the exogeneity of the variables of the DSGE with respect to some auxiliary variables. Finding evidence of non-exogeneity implies misspecification, but finding...

In this paper we examine, by means of Monte Carlo simulation, the properties of the so called 'Pantula principle' for the simultaneous determination of rank and deterministic components in a vector error correction model. Examining the five models contained within the Johansen methodology, we...

The article deals with a recent and much up to date field of econometric science not yet known to the Russian reader — financial econometrics. Terminology and concepts of different kinds of risk management as well as methods of its measurement are considered in the paper. The article is a...

This report presents an application of a macro stress testing procedure on credit risk in the Romanian banking system. Macro stress testing, i.e. assessing the vulnerability of financial systems to exceptional but plausible macroeconomic scenarios, maintains a central role in macro-prudential...

In this paper, we consider both the partial unit root and the near partial unit root processes in nonlinear transition autoregression models. Our simulations show that when these time series data are used in ordinary least squares regression, spurious regression occurs. However, if we...

La presencia de cambios estructurales en las series económicas puede conducir a conclusiones equivocadas en cuanto a su estacionariedad, hecho que aconseja el desarrollo de contrastes ampliados para contemplar la presencia de rupturas. En el caso de los tests de raíces unitarias (tipo ADF)...