Using the recently developed linearity test and non-linear unit root test, this study shows that the income gaps of Finland, Norway and Sweden with respect to Denmark are non-linear but stationary with no significant trend effect, implying the Nordic countries have already attained steady state...

Estimating the lag length of autoregressive process for a time series is a crucial econometric exercise in most economic studies. This study attempts to provide helpfully guidelines regarding the use of lag length selection criteria in determining the autoregressive lag length. The most...