Convergence of per capita sulphur dioxide emissions across US states

This study examines the stochastic conditional convergence of sulphur dioxide (SO2) emissions using the Residual Augmented Least Squares–Lagrange Multiplier (RALS–LM) unit root test with structural breaks. This procedure allows the data to account for trend breaks and nonnormal errors that have been ignored or deemphasized in previous studies. The study finds that per capita sulphur dioxide emissions exhibits stochastic conditional convergence across US states.