New evidences about convergence across states

There are many empirical studies trying to test if there is income convergence across metropolitan areas in the continental United States. Drennan.et.al (J. of Economic Geography, 2004) claim that income divergence among metropolitan economies is diverging for the period 1969-2001 by applying univariate unit root tests to the time series data. This paper brings new information to this area of study by using linear unit root tests and non-linear unit root test of Exponential Smooth Auto-Regressive Augmented Dickey- Fuller (ESTAR-ADF) unit root test to the time series data for the period 1929-2005. Our results find evidence of stationarity for time series and, thereby supporting beta and sigma convergence among states.