Interdependence of government expenditure among European countries: Productivity spillover and strategic interaction
构建内生增长模型区分生产性与福利性政府支出，利用30个欧洲国家面板数据验证生产率溢出和策略互动，发现生产率正外部性导致生产性支出投资不足，福利负外部性引发福利锦标赛。
Abstract We build an endogenous growth model that distinguishes productive and welfare government expenditures and embeds fiscal externalities. The model yields three testable hypotheses: (i) productive expenditure raises growth (Barro effect); (ii) productive expenditure generates cross‐country productivity spillovers; (iii) government expenditure structure exhibits spatial dependence. Estimation with a spatial‐panel dataset for 30 European economies (EU27 + 3) corroborates all three hypotheses. We further show that positive productivity externalities induce an international free‐rider problem, causing systematic under‐investment in productive expenditure, while negative welfare externalities trigger a “welfare tournament” and over‐spending on non‐productive expenditure.