財政政策與二氧化碳排放之關連性研究-以日本為例

本研究採用時間序列分析法，分析日本財政政策與二氧化碳之間的長期均衡與短期動態關係，日本至1990年後為了刺激經濟成長，則多次採取擴張性財政政策以舒緩經濟困境，本文為瞭解日本之財政政策與二氧化碳排放量之間關係，並驗證財政政策是否會影響二氧化碳排放。研究樣本為1980至2016年，共37年之時間序列資料，以實證方法分析二氧化碳排放量、政府支出、私人消費、私人非住宅投資以及實質GDP之關係。本文先以ADF、KPSS單根檢定來確認所有變數皆為I(1)之定態時間序列，接續以Johansen跡檢定估計法與最大概似估計法找出一組共整合向量關係，即代表變數間具有長期的均衡關係，並進一步利用向量誤差修正模型、衝擊反應函數分析變數間短期修正調整過程，透過以上計量研究方法來檢驗變數之間關連性。茲將主要研究結果摘要於下: 1. 日本財政政策是否會影響二氧化碳排放量?此兩種變數之間存在著長期的負向關係，當政府支出的增加將有助於二氧化碳排放量的減少，在短期動態調整過程發現到，當政府支出增加越多時，對二氧化碳的排放量也會得到顯著的減少效果。 2. 私人消費及私人非住宅投資對二氧化碳排放量有顯著的長期正向關係，私人消費有助於二氧化碳排放量增加，每增加一單位的私人消費都會有二氧化碳的產生，而私人非住宅投資有助於二氧化碳排放量增加，推測其原因有可能是私人部門投資於汙染較重之產業別，而非綠色能源或低汙染之產業。 3. 實質GDP對二氧化碳排放量的影響效果，呈現顯著的長期負向關係。實質GDP增加時將有助於二氧化碳排放量的減少，從1995年到2015年，可以明顯的發現到日本產業結構有所改變，因此實質GDP對二氧化碳排放量的影響效果，呈現長期負向影響。

關鍵字

日本；財政政策；二氧化碳排放；向量誤差修正模型

並列摘要

After 1990, Japan has adopted expansionary fiscal policy to alleviate economic difficulties and stimulated economic growth. This paper takes Japan’s data from 1980 to 2016 for a total of 37 years to understand whether fiscal policy will affect CO2 emissions. I empirically analyze the long-term equilibrium and short-term dynamic relationships among CO2 emissions, government expenditure, private consumption, private non-residential investment, and real GDP. In this paper, ADF unit root test and KPSS unit root test are first used to confirm that all variables are stationary of I(1). Then, Johansen co-integration test about trace test and maximum eigenvalue test are used to find a set of co-integration vector relations. The results showed that there is a long-term equilibrium relationship between them. VECM model and impulse response function are further used to analyze the short-term correction adjustment process between variables. The main findings are summarized as follows: 1. There is a long-term negative relationship between Japan’s fiscal policy and CO2 emissions. When government expenditure increases, it will reduce CO2 emissions. In the short-term dynamic adjustment process, it is found that when government expenditure increases, CO2 emissions will also be significantly reduced. This is presumably due to the government's increased investment in environmental quality. Therefore, government expenditure increases will reduce CO2 emissions. 2. Private consumption and private non-residential investment have a significant long-term positive relationship with CO2 emissions. Because the private sector invested in heavily polluting industries rather than green energy or low-pollution industries, increased private non-residential investment and consumption will increase CO2 emissions. 3. The effect of real GDP on CO2 emissions presents a significant long-term negative relationship. From 1995 to 2015, it can be found that the industrial structure of Japan has changed (the industrial part of GDP has decreased from 34.65% to 29.143%).The influence effect of real GDP to CO2 emissions demonstrate negative effect in long term.