The effect of long-run identification on impulse-response functions: An application to the relationship between macroeconomics and agriculture in Tunisia

The objective of this paper is to analyse some of the most relevant relationships among macroeconomic variables and the agricultural sector in Tunisia. Three alternative models are specified and estimated: a VAR in levels, an unrestricted Vector Error Correction Model (VECM), and a Restricted VECM in which long-run relationships among the relevant variables are identified. In all models short-run dynamics are analysed through the use of Generalised Impulse Response Functions. Results indicate that alternative model specifications generate different short-run dynamics. Long-run identification seems to be a necessary condition for obtaining consistent economic results.