This paper shows that the integrated modified OLS (IM-OLS) estimator developed for cointegrating linear regressions in Vogelsang and Wagner (2014a) can be straightforwardly extended to cointegrating multivariate polynomial regressions. These are regression models that include as explanatory...

We show that spline and wavelet series regression estimators for weakly dependent regressors attain the optimal uniform (i.e. sup-norm) convergence rate (n= log n)..p=(2p+d) of Stone (1982), where d is the number of regressors and p is the smoothness of the regression function. The optimal rate...

Since an economic or financial variable may be affected by both stationary andnonstationary variables, this paper proposes a class of augmented cointegrating linear(ACL) models that accommodate these time series of different types. Moreover, thevariables are allowed to be strongly correlated in...

We consider integrated modified least squares estimation for systems of cointegrating multivariate polynomial regressions, i. e., systems of regressions that include deterministic variables, integrated processes and products of these variables as regressors. The errors are allowed to be...

The environmental Kuznets curve predicts an inverted U-shaped relationship between air pollution and economic growth. Current analyses frequently employ models that restrict nonlinearities in the data to be explained by economic growth only. We propose a Global Trend Augmented Cointegrating...

This paper considers estimation and inference for varying-coefficient models with nonstationary regressors. We propose a nonparametric estimation method using penalized splines, which achieves the same optimal convergence rate as kernel-based methods, but enjoys computation advantages. Utilizing...