The Role of Omitted Variables in Identifying a Long-run Equilibrium Relationship for the Italian Government Growth

We discuss the role of omitted variables in the long run empirical modeling of the Italian government growth based on a Wagner's Law framework. We identify a non-spurious long-run relationship between general government expenditure and domestic product only when our Wagner's Law model is enhanced by a measure of bureaucratic power, as a supply-side variable, and by the ratio of local to state expenditure, as an institutional factor that captures the division of competencies between local and central government in allocating public expenditure. This result is independent from the Wagner's Law specification chosen. The persistence profile analysis shows a slow adjustment to equilibrium for the estimated government growth relationship following system-wide shocks, pointing to rigidities and complex functioning of the public sector.