稅制改革乃是與時俱進，配合國家社會、經濟等情勢之演變而進行。本文旨在探討發生於1930年代臺灣所進行稅制改革之背景與內容，另其重點置於研究本次稅制改革所造成的結果，以對此次稅改有更全面性之認識。 第一、探討日治時期所得稅的引進與發展。本次稅制改革除順應戰前臺灣的租稅結構中，所得稅自創設以來明顯之成長趨勢外，更因所得稅具備戰時租稅、符合公平正義及具備彈性等特質，因此成為本次稅制改革所欲發展的重心。 第二、探討稅制改革後直接稅比重之變化。在國稅體系或國稅與地方稅體系合併考量下，直接稅佔稅收的比重皆於1937年稅制改革當年度超越間接稅比重。平均而言，本次稅制改革確實達到提高直接稅比重之目的。 第三、研究稅收增加對國家財政之改善情形。稅制改革後，稅收之成長皆對中央或地方政府之決算剩餘產生了相當程度的幫助與改善。本次稅制改革雖以增稅為主要目標，然1937年至1941年間臺灣人民的租稅負擔仍不算沉重。至稅制改革後，稅收所得彈性大部分年度呈現大於1之情況，顯示國家租稅收入增加幅度超越國內生產毛額成長幅度的現象。

遺產及贈與稅的課徵具有實現社會公平的正面意義，但開徵至今，不僅稅收不豐，更因租稅規避行為普遍而失去效率，我國遂於2009年針對遺產及贈與稅制進行大幅改革。 　　本研究以美國、香港及新加坡的稅制實施與改革經驗為借鏡，輔以財政部國稅局的實際課徵數據，探討此次遺贈稅制改革的內容與影響。研究發現，此次遺贈稅改的影響，於短期會造成遺贈稅的稅收損失，但就長期而言，因稽徵效率提升及降低民眾跨期與跨區配置資源的條件限制，可增進整體社會資源的配置效率。此外，調降後的遺贈稅稅率約與租稅規劃成本相當，可望減緩我國資金外流的情形；惟仍須配合國內政治、經濟及社會環境之發展，方有足夠誘因吸引資金回流。 　　是故，本研究建議政府機關應有明確之政策發展方向，如欲以租稅政策促進經濟發展，應先正視我國目前面臨的競爭環境及資金流向問題，塑造優良投資環境，方能吸引資金回流，活絡我國經濟並培養適當稅源。再者，亦應確立遺贈稅制之定位，於未來改革方向，不論再降稅或廢除，均應規劃妥善之配套措施，使我國整體賦稅制度更臻完善。 / The estate and gift taxes are most often justified by the need to ensure a particular sense of fairness in the overall tax system. However, the two contribute to a rather insignificant share to total tax collection, and also encourage widespread tax avoidance. Thus, many economists argue that the estate and gift taxes are hard to justify on either efficiency or equity grounds. For these reasons, the Estate and Gift Tax Act in Taiwan was substantially revised in January, 2009. The main purpose of this study is to explore the major revisions and the impact of the tax reform, supported by the financial statistics offered by the Ministry of Finance, R.O.C. The results of this study indicate that the significant revision will lead to a reduction in tax revenue in the short term. Neverthetheless, it will make the allocation of resources in the economy more efficient in the long term, since the collection efficiency of the two taxes improves and the restriction on allocation of resources for the public is reduced. Besides, the new tax rate is nearly equal to the cost of tax planning, so the capital outflow may be eased off. If the government and regulatory bodies also improve the investment environment, it will attract more foreign capital back to Taiwan. Based on the above, this study provides some suggestions for the tax administration. First, it is necessary to set a clear policy direction. If policy makers intend to use tax policies as a tool for promoting economic development, it is important to address the issues which our country currently encounters with, including the competitive economic environment and where the capital flows to. Only with the better investment environment, can our country attract more international capital to invest in. Second, tax administration must establish the role played by estate and gift taxation in our tax system. Any reforms of the estate and gift taxes must entail a set of complementary measures, so that our tax system could be fairer and more efficient.

隨著全球暖化問題日益嚴重，許多歐洲國家於1990年代遂進行一連串的綠色稅制改革，盼透過課徵環境稅的方式有效改善環境問題；本研究即以綠色稅制改革的先驅者—歐洲15國作為研究對象，觀察期間為1995年至2005年，利用計量方法探討能源相關稅制對溫室氣體減量之真實效果。 研究發現課徵碳稅、能源稅等與污染排放相關之環境稅，確實能有效降低二氧化碳等溫室氣體的排放量；但以車輛為稅基的交通運輸稅類別環境稅則未能產生改善環境的作用。此外，研究結果顯示提高能源價格亦有助於降低二氧化碳等溫室氣體之排放量，而能源密度、發電結構及工業導向之產業結構皆為提高二氧化碳等溫室氣體之重要因素；且全部的國家皆因各自的天然環境等特質而產生二氧化碳等溫室氣體排放量固定效果。 根據實證結果，本研究提出以下建議： 一、 世界各國皆應加快腳步研擬一套因地制宜的綠色稅制，；亦可將能源相關環境稅之課徵與能源價格調升交互運用。 二、 應著重於直接對污染排放及燃料使用課稅，且可考慮廢除沒有實際改善環境效果的車輛稅、牌照稅等交通運輸稅。 三、 需深入思考經濟發展與環境永續發展間的抵換關係，若遇開發中國家礙於經濟發展需求及國家能力而無法於短期內轉型之情況，已開發國家亦應遵循京都議定書之相關內容及規定，盡力予以協助。

本論文在實質與貨幣內生成長模型中探討政府租稅的效果，而其中又以稅制改革政策為主角。 在第二章中，我們將內生生育率的概念引入了Romer (1986)的實質經濟成長模型，並說明當政府在維持稅收中立的原則下將所得稅制轉換為消費稅制時，將可能對經濟成長與社會福利有所傷害。而後我們也提供了一些數值模擬以支持我們的論點。至於第三章，我們將勞動供給內生的概念引入一個有預付現金限制(Cash-in-Advance)的貨幣經濟成模型，在本章中我們得到了所謂「Mundell-Tobin Effect」與「消費稅中立性」的成立與否，將取決於政府稅收的用途；接著我們把焦點放在資本的生產外部性與消費稅所造成的扭曲上並導出最適貨幣政策；最後，在維持政府的支出水準下，我們得到將消費稅制轉換為通膨稅制時，將對經濟成長有正面的效果。 / The dissertation provides a theoretical framework to investigate the effects of tax policies, especially the tax reform, in real and monetary models of endogenous growth. In Chapter 2, by shedding light on the endogenous fertility choice, we set up a simple Romer (1986)-type endogenous growth model and show that, in a departure from the existing literature, a switch from a decrease in income tax rate to an increase in consumption tax rate so as to ensure a revenue-neutrality could be harmful, rather than favorable, to both growth and welfare. In addition, we also conduct a simple numerical analysis to investigate the conditions in which the negative effect on growth and welfare occurs. As to the monetary model, an endogenous growth model with endogenous labor-leisure choice and cash-in-advance (CIA) constraint which is only imposed on consumption is established in Chapter 3. Through the model, we found that the Mundell-Tobin effect and the validity of consumption tax neutrality depend on the usages of tax revenue. Next, focusing on the distortions due to the production externality of capital and consumption tax, the optimal monetary policy is also derived. Finally, we show that a switch from consumption taxation to inflation taxation to finance a given stream of government expenditure, namely tax switch, enhances economic growth through the increase in labor supply in a CIA economy and the qualitative equivalence between MIU and CIA approaches is still valid.

綠色稅制改革始於1990年代，在此前歐美主要稅收所得來源為所得稅，隨著歐美國家面臨經濟與財政困境，課稅項目漸漸地轉向環境稅，最先實施的國家為北歐國家，目前我國正面臨經濟衰退，且新政府上任後，增稅政策屢屢遭到民眾的反彈，有些學者認為，環境稅有辦法達成「雙重紅利」，既能增進環境品質且改善所得分配，不失為一向好的課稅工具。 本研究以民國100年行政院主計處的「產業關聯表」與「家庭收支調查報告」估計綠色稅制改革的所得重分配效果，利用投入產出分析法，估計環境稅對於消費支出項目價格影響，再將環境稅稅收金額作為所得稅減免與移轉收入減免用途，最後估計吉尼係數，觀察實施綠色稅制改革後的所得重分配效果。 實證結果顯示，環境稅是一具有累退性質之租稅，故單純課徵環境稅會造成所得分配惡化，且課徵越高之金額，所得分配惡化越嚴重；實施綠色稅制改革後，所得分配都較原始值平均，且綠色稅制改革金額越大之方案，改善所得分配效果則越好。

本研究利用台灣2001年資料以Ramsey與OLG假設分別建立區分四部門別與八部門別之動態可計算一般均衡模型，進行「提高間接稅（消費稅、環境稅）、降低直接稅（資本、勞動所得稅）」之稅制改革模擬分析。結果發現若以單一時點比較靜態方式分析可能迥異於動態長期分析結果；其次以Ramsey分析所欠缺的代際分配影響結果在OLG分析中可以察見，特別是進行以消費稅或環境稅替代資本所得稅模擬時；再者OLG因代際傳遞效果可能較Ramsey假設下反應緩慢，故也可觀察到Ramsey模型面對衝擊後若干變數增減幅度會較OLG模型陡峭。最後特別在環境稅替代所得稅模擬中經由替代稅率變化發現，活在初期世代雖可享受所得稅下降好處但卻也面臨排放稅課徵，因此福利水準增減變化不大，惟屆至排放稅課徵瀕至臨界點需使用原所得稅來平衡稅收時，此為另一波必須為減量政策付出代價的時點與世代。 / Based on a thorough comparison of the basic assumptions and economic underpinning of the Ramsey and Overlapping generation (OLG) model, this study builds both static and dynamic computable general equilibrium tax policy models to analyze the effect of tax reform on Taiwan’s economy. The new tax structure considers mainly a replacement of some parts of direct tax - labor and capital income taxes by indirect tax- consumption tax or environment tax. The benchmark year of the model is 2001, and the economy is divided into four and eight sectors. The modeling framework is implemented on top of MPSGE, which is a special module within the General Algebraic Modeling System (GAMS).Our simulation results show differential outcomes for static and dynamic models. The slower speed of transition inherent in OLG model has caused variables such as welfare, capital stock, and replacement consumption tax rate change less than that in the Ramsey model when the tax reform policy is imposed. And the intergeneration effects of different tax burden between young and old generations can be found in the OLG model but not in the Ramsey model. Finally, we find as the income tax rate coming lower and the environment tax going up when simulation of tax replacement, causing the welfare does not change much at the beginning of shock, and generations especially born in the near future when environment tax does not grow and revenue neutrality needs to be meet are another cost payers of abatement policy.