Marialaura Pesce Dept Mathematics and Statistics and CSEF - Centre for Studies in Economics and Finance   via Cinthia, Complesso Monte S.Angelo Naples, 80126 Italy   marialaura.pesce@unina.it   http://www.csef.it/people/pesce.htm           JEL Areas: D5 : General Equilibrium and Disequilibrium: General H5 : National Government Expenditures and Related Policies National Government Expenditures and Related Policies: General