本文的主要目的是分別探討在國內與國際耗盡原則下，所得不均惡化對本國製造商與外國代理商策略及其利潤、與兩國的消費者剩餘與社會福利之影響有何不同。我們的研究發現，若本國採國內耗盡原則，兩國所得不均度惡化使本國製造商會降低產品品質，批發價先降後升。同時，製造商與代理商的利潤皆會下降。此外，兩國消費者剩餘皆上升，且兩國社會福利會先降後升。若本國採國際耗盡原則之下，在平行貿易發生後，本國所得不均度增加可能使批發價提高(不會下降)。外國所得不均度增加可能使外國的社會福利會下降(不會上升)。此外，我們還發現了，在國際耗盡原則之下，若製造商所在的國家其所得不均度較高時，此時外國的代理商有意願回賣。在平行貿易之下，製造商降低生產的產品品質，且會提高代理商的批發價。同時，兩廠商的利潤均減少。此外，本國消費者剩餘增加，外國消費者剩餘減少，使本國社會福利增加，外國社會福利減少。但兩國總福利會減少。

This paper aims to examine how income inequality affects the strategies and profits of domestic manufacturer and foreign distributor, and their impacts on the consumer surplus and social welfare of the two countries under the two different regimes of national and international exhaustion, respectively. Our results show that, under the national regime, when income inequality is getting worse in the two countries, the domestic manufacturer reduces its product quality, and the wholesale price first fall and then rise. The profits of the manufacturer and distributor both fall. In addition, the consumer surpluses in the two countries both increase while the social welfare in both countries fall first and then rise. Furthermore, we show that, under the international regime, the parallel trade occurs, only when the home country with the manufacturer has higher income inequality. With parallel trade, manufacturer reduces its product quality and increase the wholesale prices for the distributor. The profits of manufacturer and distributor both decrease. In addition, the consumer surplus in the home country increases, while the consumer surplus in the foreign country decreases, resulting in an increase in home country’s social welfare and a decrease in foreign country’s social welfare. Besides, the total welfare of the two countries both decrease.

學位論文審定書.........................................i
摘要...........................................................ii
Abstract...................................................iii
一、前言....................................................1
二、文獻回顧............................................4
三、模型設定............................................6
四、國內耗盡原則....................................8
五、國際耗盡原則..................................14
六、結論..................................................20
參考文獻..................................................21
附錄..........................................................22

Gabszewicz, J. and J.F. Thisse (1979) Price competition, quality and income disparities,
Journal of Economic Theory, 20, 340--359.
Hwang, H., C. Peng and P. Shih (2014) Parallel Imports, product innovation and market
structure, International Review of Economics and Finance, 34, 237–245.
Matteucci, G. and P. Reverberi (2014) Parallel trade, product quality and welfare.
Economics Letters, 122, 258–262.
Motta, M. (1993) Endogenous quality choice: price v.s.quantity competition. Journal of
Industrial Economics, 41, 113-131.
Reisinger, M., L. Saurí and H. Zenger (2019) Parallel imports, price controls and
innovation. Journal of Health Economics, 66, 163-179.
Shih, P.C., Y.S. Lin and F.Y. Chen (2017) Profit-enhancing parallel imports in the
presence of vertical control. Keynote speech, Department of Economics, National
Chung Cheng University