In this paper, we propose two parametric alternatives to the standard GARCH model. They allow the conditional variance to have a smooth time-varying structure of either additive or multiplicative type. The suggested parameterizations describe both nonlinearity and structural change in the...

In this paper we analyze the validity of the purchasing power parity (PPP) in a nonlinear framework using data for 18 bilateral US dollar exchange rates. Following Enders and Ludlow (2002), we use unit root and cointegration tests that do not assume a specific nonlinear adjustment. We find...

We propose information theoretic tests for serial independence and linearity in time series against nonlinear dependence on lagged variables, based on the conditional mutual information. The conditional mutual information, which is a general measure for dependence, is estimated using the...

The standard procedure for analyzing transitional dynamics in non-linear macro models has been to employ linear approximations. This paper investigates the reliability of this procedure in evaluating the dynamic adjustments to policy changes or structural shocks. We analyze this issue using the...

The purpose of the present paper is to relate two important concepts of time series analysis, namely, nonlinearity and persistence. Traditional measures of persistence are based on correlations or periodograms, which may be inappropriate under nonlinearity and/or non-Gaussianity. This article...

This article proposes a simulation approach to obtain least-squares or generalized least-squares estimators of structural nonlinear errors-in-variables models. The proposed estimators are computationally attractive because they do not need numerical integration nor huge numbers of simulations...

This paper proposes a simple chartist-fundamentalist model in which we allow for nonlinear time variation in chartists' extrapolation rate. Estimation of the model using monthly data for the major currencies vis-a-vis the US dollar shows that the model is significant in-sample and that it has...

Under some regularity conditions, the paper provides an alternative proof for the revised moment conditions proposed by Hong and Tamer (2003) in the nonlinear least squares regression model, when the covariates are measured with Laplace error. The asymptotic normality of the revised moment...