In this paper we present a unit root test against a nonlinear dynamic heterogenous panel with each cross section modelled as an LSTAR model. All parameters are viewed as cross section specific. We allow for serially correlated residuals over time and heterogenous variance among cross sections....

In this paper we derive tests for parameter constancy when the data generating process is non-stationary against the hypothesis that the parameters of the model change smoothly over time. To obtain the asymptotic distributions of the tests we generalize many theoretical results, as well as new...

In this paper we derive a unit root test against a Panel Logistic Smooth Transition Autoregressive (PLSTAR). The analysis is concentrated on the case where the time dimension is fixed and the cross section dimension tends to infinity. Under the null hypothesis of a unit root, we show that the...

This paper examines aggregate savings in a general equilibrium model where infinitely lived households face volatile (and possibly uncertain) income paths, hold a risk-free asset, and face a liquidity constraint. I first show that the equilibrium capital stock in an economy without uncertainty,...

The constant conditional correlation GARCH model is probably the most frequently applied multivariate GARCH model. In this paper we consider an extension to this model and examine its fourth-moment structure. The extension, first considered by Jeantheau (1998), is motivated by the result found...

In this paper we derive conditions for the conditional covariance matrix to be positive definite in a general vector ARCH model. The conditions can be easily extended to the diagonal vector GARCH model. For the general vector GARCH model, analytical expressions for the conditions in terms of the...

The labor-supply elasticity is a central element in many macroeconomic models. We argue that assumptions underlying previous econometric estimates of the intertemporal labor supply elasticity are inconsistent with incomplete markets economies. In particular, if the econometrician ignores...

We use the neoclassical growth framework to model international capital flows in an economy with exogenous demographic change. We compare model implications and actual current account data and find that the model explains a small but significant fraction of capital flows between OECD countries,...