財政赤字與財政支出關係的檢驗──Buchanan-Wagner假說成立嗎？

An Examination of the Public Deficits and Government Spending Relationship: Does the Buchanan-Wagner Hypothesis Hold?

本文探討我國實質政府總支出、政府賦稅收入占實質政府總支出比率、每人實質所得、私部門工資率與總納稅人口數等5個變數之間的長期均衡及動態調整關係，據以檢測台灣地區財政赤字與實質政府總支出之間是否具有長期正向關係（支持Buchanan-Wagner假說）。此外也檢測每人實質所得增加是否會帶動實質政府總支出增加，若實質政府總支出的所得彈性大於1，則表示支持華格納法則（Wagner's Law）。本文的實證結果顯示：一、上述5個變數之間具有長期均衡關係。二、台灣地區財政赤字與實質政府總支出具有顯著的正向關係，即提高財政赤字會促使實質政府總支出增加，支持Buchanan-Wagner假說。三、每人實質所得增加，會帶動實質政府總支出增加，但所得彈性小於1，表示Wagner法則在台灣無法成立，但若將實質政府總支出細分為實質政府經常支出與實質政府資本支出，則Wagner法則成立與否會因財政支出型態的不同而有差異，即實質政府經常支出成立，而實質政府資本支出不成立。四、公部門的生產效率低於私部門的生產效率。五、實質政府總支出因人口的增加而有規模經濟現象。

This paper provides a full discussion of the long-run co-movements and the short-run dynamic adjustment relationships among government spending, public deficits, income, wages, and adult population in a multivariate model. This paper aims to investigate the issue of whether there is a long-run positive relationship between real government spending and public deficits supporting the Buchanan-Wagner hypothesis in Taiwan. Moreover, we also explore whether real per capita income stimulates real government spending. If the income elasticity of demand for government spending exceeds unity, then the Wagner's Law should be supported. Our main findings are as follows. First, we find substantive evidence in favour of the existence of a long-run equilibrium relationship among the above variables. Second, the empirical results demonstrate that public deficits and government spending have a significantly positive relationship, which provides a strong support for the Buchanan-Wagner hypothesis. This means that high deficits produce higher levels of government spending. Third, increasing real per capita income promotes real government spending, but the income elasticity is less than one indicating the Wagner's Law finds no statistical support in Taiwan. Fourth, productivity in the public sector is lower than in the private sector. Finally, scale economy exists in the provision of government services.