本文主要探討民主化程度與所得不均間的關係是否會因所得水準不同而有所差異。運用95個國家，1981年至2013年的橫斷面資料並以門檻迴歸進行分析。

本文以民主規模-獨裁規模的差 (Democracy) 做為衡量民主化程度的指標，以吉尼 (Gini) 係數的成長率作為衡量所得不均的指標，以所得水準為門檻變數。結果發現在低所得的國家，民主化程度與所得不均間存在負向且顯著的關係，說明在低所得的國家中民主化程度上升是可以減緩所得不均；而在中高所得國家與高所得國家，民主化程度與所得不均間存在正向且顯著的關係，說明在中高所得國家與高所得國家民主化程度提高反而會使所得不均的情況更為惡化。

This paper tries to investigate the threshold effects of democracy on income inequality. Specifically, we use Hansen’s (2000) threshold regression model to examine the democracy- inequality links varies with the degree of country’s income level. By applying the model to 95 countries during the period 1981-2013, we find that there indeed exists an income threshold in the democracy- inequality link. 
The empirical results show that low-income countries have a negative and significant relationship between the democracy and income inequality.  However, the relation is positive and significant in the middle-income countries and high-income countries.  It indicates that the increasing in the degree of democratization would reduce income inequality in low-income countries, but increase income inequality in the middle-income countries and high-income countries.

目錄
目錄 Ⅰ
表目錄 Ⅱ
第一章 緒論 1
第一節 研究動機與目的 1
第二節 研究方法與架構 3
第二章 文獻回顧 5
第一節 民主化程度與所得不均呈負向關係 5
第二節 民主化程度無法消除所得不均的影響 8
第三節 民主化程度與所得不均間的雙向關係 11
第四節 所得與民主間呈正向關係 13
第三章 研究方法 17
第一節  HANSEN 門檻迴歸模型 18
第二節  資料來源與敘述 21
第四章  實證分析	28
第一節  門檻迴歸1	28
第二節  門檻迴歸2	31
第五章 結論與建議	33
參考文獻	34
附錄 39

表目錄
表2.1 民主化程度所得不均間的關係 15
表3.1 樣本國家 25
表3.2 敘述統計表 27
表3.3 相關係數矩陣 27
表4.1 吉尼係數成長率與民主化程度指標之門檻關係(一)	30
表4.2 吉尼係數成長率與民主化程度指標之門檻關係(二)	32

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