本研究以美國、英國及日本三個國家從1980年代至2007年公司所得稅制改革方向為主要探訪對象，包括了降低（增加）公司所得稅稅率、擴大稅基及賦 予租稅優惠三個措施，分析瞭解各國所採取方式。 1980年代美國、英國、日本三個國家在公司稅制改革均採降低公司所得稅稅率、擴大稅基及賦予租稅優惠三種方式。 1990年代美國公司稅制改革係採提高公司所得稅稅率及賦予租稅優惠方式，英國及日本公司稅制改革係採降低公司所得稅稅率、擴大稅基及賦予租稅優惠三種方式。 2000年至2007年美國、英國、日本三國在公司稅制改革，除了美國於2004年降低製造業公司所得稅稅率，及英國2002年至2005年給予小公司所得稅稅率優惠與加強反避稅措施之擴大稅基方式外，主要採用賦予租稅優惠方式。

影響公司資本結構的理論大體可區分為由租稅、稅盾和破產成本間的互抵關係（trade-off）、由經理人、債權人、以及股東間因利益衝突所引發的代理成本（agency cost）、以及融資順位理論（pecking order theory）等觀點來討論。其中，租稅因素包括有效稅率、以及投資抵減、租稅損失遞延等非負債性稅盾因素。而另一方面，影響有效稅率的因素則包含了公司的資本結構、公司規模、盈餘變動、各項租稅優惠等因素。很明顯的，資本結構與有效稅率兩者間有互為因果、以及聯立的關係存在。但在過去的研究中卻均未考慮到此點，目前的文獻或只論及有效稅率對資本結構之影響，或是資本結構對有效稅率之影響，均為單一方向的考慮，忽略了兩者之間相互影響的關係，因此所得之實證結果也必然有所偏誤。 因此，本文以一全新、與以往不同的聯立方程系統，而非尋舊有兩條分立之模型的方式，就實證結果來分析效稅率與資本結構之間真正的關係，並同時以橫斷面、及Panel Data之固定效果模型來進行迴歸分析。其主要結論為：我國公司之有效稅率與資本結構只存在負相關之結果，當有效稅率愈高（低），公司之舉債愈低（高），也就是說，利息費用所帶來的租稅節餘利益並不影響我國上市上櫃公司之資本結構。此結果不僅與理論不符，也與國內之前之實證研究結果相異。本文推論，這可能與投資抵減所帶來的所得效果、以及股票市場之之蓬勃發展有關。 另外，本文亦針對台灣資本市場以及稅制環境之特色，納入台灣目前停徵證券交易所得稅及土地交易所得稅之因素。實證結果顯示，免稅之證券交易所得與資本結構為負相關，反映出了台灣近幾年股票市場交易熱絡，以及公司以此作為其財務融資來源的特色，租稅因素對於公司融資行為之影響由此可見。這對於租稅中立的追求來說，並不是一個令人樂見之結果。

新企業所得稅法實施後，內外資企業所得稅法被統一，不一致的情形被消弭，稅收優惠的政策也從對外資企業的普遍優惠制轉變成以產業為導向。凡此種種改變，皆對中國大陸上市企業之有效稅率產生影響。本文以2003年-2010年中國大陸上市企業的財務資料做實證研究。 本文主要研究的課題有三：一、探討新企業所得稅法實施前後稅前扣除規定對有效稅率的影響；二、新企業所得稅法中規定的反資本弱化條款對企業有效稅率是否有影響？；三、內外資企業所得稅兩稅合一之後，各地區是否仍有顯著的稅境差異？ 第一個課題用兩個變數來捕捉，一個是薪資費用，一個是營運費用。薪資費用在內外資企業所得稅兩稅合一前與有效稅率為負相關。本文推論該情形因為高階管理人員的薪資沒有正常列報，而可能的原因有三：一、租稅規劃原因，二、避免薪酬過高引起社會各界關注，故分配在各個關係企業，三、國家對國有企業的高階管理人薪資有限制。 營運費用在內外資企業所得稅兩稅合一前與有效稅率為正相關，與假說預計情況相同。這部分可用財稅差異的觀點來解釋。而內外資企業所得稅兩稅合一之後，應納稅所得額的計算規則更為公平合理，故營運費用對有效稅率的影響為負相關。第二個課題是討論資本弱化條款的問題。內外資企業所得稅兩稅合一之後，該變數之係數呈現顯著正相關，代表中國大陸在內外資企業所得稅兩稅合一之後，反避稅措施的實施已然有些成效。 第三個課題是稅境差異的問題。本文地區性虛擬變數的設置以西部地區為對照組。內外資企業所得稅兩稅合一之前，較明顯享受稅收優惠政策的地區是西部地區與經濟特區，故東部地區與中部地區的係數顯著為正，而經濟地區呈現不顯著的狀態。內外資企業所得稅兩稅合一之後，地區別的稅收優惠政策只剩下西部地區中的鼓勵類產業才能享受，而實證結果也明確顯示中國大陸政府預期的結果。 / After new enterprise income tax law enacted , income tax law applicable to both domestic and foreign-owned enterprise are unified,the difference between those income tax law are gone. The new law scraps the original emphasis on regional incentives in favor of industry-oriented incentives supplemented by regional ones . All of these changes affect corporate effective tax rates of China Listed companies . This study used the sample of china listed companies spanning from 2003-2010. This study have three main topics : First, to discuss how the pre-tax deduction rules affect corporate effective tax rates before and after implementation of the new law. Second, does the anti-thin capitalization rule in the new law have some effect to corporate effective tax rates? Third, after implementation of the new law,are there still big difference between regions? This study used two variables to examine first topic-salary expense and operating expense. Salary expense had a negative correlation with corporate effective tax rates before implementation of the new law. I consider it came from salary information disclosure of senior executives which could be explained in three ways. First, tax planning purpose. Second, in case of drawing attention from publics, part of salary were paid by affiliated companys. Third,the country imposed caps on senior executive pay in state-owned enterprises. Operating expense had a positive relation with corporate effective tax rates before implementation of the new law which is the same as hypothesis. It could be explained in terms of book-tax differences. After implementation of the new law, rules for computation taxable income are more fair and reasonable. As a result, operating expense has a negative relation with corporate effective tax rates. The second topic discuss about anti-thin capitalization rule.After implementation of the new law, the variable standing for anti-thin capitalization rule is significantly positively correlated with corporate effective tax rates.It represents that, after implementation of the new law, China authorities make progress in anti-tax avoidance. The third topic is about tax burden between regions. This study used western region as a control group. Before implementation of the new law, preferential tax policies were subject to western region and Special Economic Zones. For this reason, the region dummy variables—central China and east China were significantly positively correlated with corporate effective tax rates, but the coefficient of western region dummy variable did not reach statistical significance. After implemention of the new law, preferential tax policies is subject only to domestic enterprises belonging to the category encouraged by the State in western region. The empirical results conform to the anticipation of China authorities.

中國大陸自1994年採用生產型增值稅後，重複課稅阻礙了產業結構的發展，使企業成長受到抑制，故2009年轉型為消費型增值稅，雖已有學者針對法治層面進行研究，然而尚無文獻針對增值稅轉型對於增值稅實質稅負之影響進行實證研究。本研究初以產業結構、股權結構與地區結構之差異探討對於中國大陸為轉型消費型增值稅後對於實質稅率產生之影響，並輔以企業規模、銷貨毛利率、股東權益報酬率、資本資產密集度……等變數的控制，期以降低對主要測量變數之影響。 實證結果發現: （1）中國大陸上市公司之有效稅率在增值稅體系中享有租稅優惠而使實際繳納之有效稅率降低，2009年後實施消費型增值稅，其實質稅率亦從4.79％降至4.02％，顯見實施後的實質稅率確能降低租稅負擔。（2）資本密集度較高之產業，其實質稅率亦較高，2009增值稅轉型後，無論是資本密集度高之產業抑或資本密集度低之產業，其實質稅率之影響並不顯著，顯見此次轉型因增值稅與營業稅並存而無法真正體現消費型增值稅所帶來稅負公平性。（3）內資持股比例超過50％之上市公司（內資企業）經過此次轉型後其實質稅率並未下降，顯見此次轉型並非全面而使成效有限。（4）中部和西部地區相較於東部地區之實質稅率較高，在2009年轉型為消費型增值稅後有降低之趨勢。 / This study investigates the effect of the effective tax rate after china began the transition from production-type valued-added tax to consumption-type VAT. Some researchers explore the pros and cons from the institutional level, but it is rarely to analyze the impact of the effective tax rate when the authorized implemented the consumption valued-added tax. This paper analyzes the effect of the effective tax rate on the transformation of valued-added tax by means of the empirical study. The empirical findings indicate that: 1) The effective tax rate of china listed companies declined from 4.79% to 4.02% after the transition of the VAT(Valued-added Tax),Therefore, the transition of the valued-added tax can decrease the burden of tax. 2) This study divided industries into capital intensive industries with high and low indicates it is not obvious in the regression. Because valued-added tax and business tax co-exist which results in the lack of fairness in consumption-type VAT. 3) The listed companies whose proportion of domestic ownership is above 50%(defined as domestic enterprises)increase rather than decrease effective tax rate after transition of VAT in 2009. 4) The listed companies which belong to area with middle and western region have decreasing tendency toward effective tax rate after transition of VAT in 2009.

本研究以民國86年至民國93年上市公司財務報表資料探討我國企業赴中國大陸投資相關因素對有效稅率的影響。經本研究實證結果發現，有赴中國大陸投資的上市公司其有效稅率低於未赴中國大陸投資者；上市公司透過間接方式投資大陸地區之比重愈高者以及大陸地區投資獲利愈高者，由於有較多租稅規劃的空間，其有效稅率愈低。整體而言，在研究期間中，我國上市公司之平均有效稅率明顯低於營利事業所得稅名目最高邊際稅率；公司規模對有效稅率有負向影響，符合政治權力假說；本研究以長期負債、固定資產、存貨、研究發展費用做為投資理財決策的代理變數，皆與有效稅率呈現負相關，因此投資理財決策具有稅盾效果，可以降低公司稅負；另外，上市公司的獲利能力愈佳，有效稅率也愈高；證券以及土地交易所得等免稅所得較多的上市公司，有效稅率較低。上述分析顯示，上市公司赴中國大陸投資因素對於其租稅負擔有顯著影響，值得政府有關單位做為研擬相關法規的參考。 / This study uses 1997-2004 financial statement data to explore the relationships between investment in Mainland China and the effective tax rates (ETRs) of listed companies in Taiwan. The empirical results show that investment in Mainland China of the listed companies has a negative and significant impact on the ETRs. This study finds that ETRs is negatively related with the scale of indirect investment and the level of profit of subsidiaries in Mainland China, perhaps due to a higher flexibility and feasibility of tax planning. Our results also reveal that average ETRs of listed companies are substantially lower than the statutory tax rate of the Income Tax Act of R.O.C. Small firms are more likely to have greater ETRs, supporting the political power hypothesis. Moreover, because of the tax shield effects, long-term debts, fixed assets, inventories, and R&D expenses, all as proxies for the financial decisions, have negative and significant impacts on the ETRs of listed companies. Finally, ceteris paribus, profitable companies tend to have higher ETRs, and tax-exempt capital gains from stock and land transactions also reduce the ETRs of listed companies. These findings indicate that investment in Mainland China by listed companies plays an important role in their tax burdens, and this fact should be taken into account by the government in devising future tax reforms.

面對經濟景氣停滯、財政赤字急遽惡化及相關社會福利支出等種種不利因素，我國政府在衡酌國際金融危機及稅制改革潮流下，於2009年將遺贈稅之最高邊際稅率由50％大幅調降為單一稅率10％，同時提高免稅額。就修法目的而言，主要希望藉由稅率的降低來吸引海外資金，並預期此項租稅改革能振興國內投資，進而穩健國內財政。 本研究利用財政部國稅局的實際課徵資料，並輔以美國、南韓、日本等國之稅制改革經驗為借鏡，分別就遺產及贈與稅之稅收變動、稽徵成本、違章漏稅等多個面向，分析遺贈稅修正後是否收得其效及其對稅賦之影響。研究結果發現，除稽徵效率有待改善外，我國遺贈稅稅賦收入於修法後並未有重大改變，主要係因海外資金實有回流，使得稅率在大幅降低的情形下，稅基並未受到侵蝕，顯見該次修法係有符合最初的預期及社會之期待。 / Facing with several unfavorable factors such as economic downturn, budget deficits, and enormous social welfare expenditures, Taiwanese government decided to lead a reform of current tax system by dropping the highest marginal tax rate of estate and gift tax from 50% to single tax rate of 10% and raising the exemption. The main purpose of this amendment is to attract foreign capitals, stimulate domestic consumptions and investments, and ultimately revitalize the economy and stabilize domestic finance. This study examines the effect of dropping estate and gift tax rate. Based on actual imposition data collected from Ministry of Finance, and experiences of United States, South Korea, Japan and other countries. I find that except for the process of tax collection is not efficient as expected, there is no significant change of tax revenue after amendment of estate and gift tax law, the reason is that the inflow of overseas funds increases the tax base. Overall, the reform of estate and gift tax does meet the initial expectation.

為分析長期與短期公司避稅行為之決定因素以及相關產業效果，本文以實證 方法檢視租稅規避行為之決定因素，並以現金有效稅率及調整後財稅差異作避稅 指標，研究對象為 2002 年至 2012 年之台灣上市櫃公司，同時排除性質特殊之金融業以及臺灣存託憑證(TDR)。 首先，本文採固定效果模型進行短期避稅行為之分析，其實證結果顯示當企 業知名度較高、研發投資較多、負債資產比較高、投資損失較多及關係企業設立 在租稅天堂時，企業積極從事避稅行為的可能性較低。另一方面，結果顯示當企 業持有固定資產較多、投資利益較多、獲利較多及有前期淨營業損失時，企業積 極從事避稅行為的可能性較高。 其次，本文採普通最小平方法模型進行長期避稅行為之分析，其實證結果顯 示當企業長期知名度較高、負債較多、投資損失較多及獲利較多時，企業積極從 事長期避稅行為的可能性較低。另一方面，結果顯示企業長期固定資產較多、研 發投資較多及投資利益較多時，企業積極從事長期避稅行為的可能性較高。 最後，為觀察個別產業之避稅行為，本研究進行平均值差異數 T 檢定、長期 普通最小平方法回歸結果以及 F 檢定，結果顯示：半導體業、建材營造業等產業 積極從事避稅行為的可能性較高。另一方面，觀光事業、油電燃氣等產業積極從 事避稅行為的可能性較低。

本文以 Barnett (1980) 一文為基礎，採用第三地市場以納入廠商型態為多國籍企業 (multinational enterprise) 的模型。本文旨在分析當兩國政府面對獨占廠商的生產不效率及製造過程中汙染排放引發的生產外部性時，如何制定最適汙染稅稅率。並比較經濟開放後資本要素可自由於兩國間移動，最適汙染稅稅率會如何變化。 本研究發現政府課稅將受三種效果影響：消費者剩餘效果 (consumer surplus effect)、利潤移轉效果 (profit-shifting effect)、汙染控制效果 (pollution control effect)。不論在封閉經濟體系或開放經濟體系下，當消費者剩餘效果大於利潤移轉效果時，政府會將最適汙染稅率制定低於皮古稅 (Pigouvian tax)，以補貼獨占廠商增加產量以提高社會福利；若利潤移轉效果大於消費者剩餘效果時，最適汙染稅稅率將高於皮古稅，以藉由汙染稅獲取更多的企業利潤。 當經濟開放後資本可於兩國間自由移動，除原先稅率對產量的直接效果(direct effect) 外，稅率亦會透過資本間接影響產量，為間接效果 (indirect effect)。間接效果將使產量對於稅率的變動較不敏感，因此為吸引具流動性的資本要素進入當地投資，政府會將汙染稅稅率調高以獲取更多企業利潤。 / Based on the setting of Barnett (1980), the thesis develops a model to analyze the optimal pollution tax on multinational enterprises with negative externalities. Governments have only one policy variable: the pollution tax. Each government levies the pollution tax on the output of multinational enterprises, and the tax revenues are returned to the residents in a lump sum manner. The purpose of this thesis is to explore the optimal taxation on the multinational enterprise with externalities and mobile capital flow. The thesis obtains several results: First, no matter in the case of closed economy or open economy, the second-best optimal pollution tax may be less or greater than the marginal pollution damage. It may be lower because the consumer surplus effect dominates the profit-shifting effect, so the government chooses a lower tax rate to stimulate production and to increase social welfare. Second, when the capital can freely move between countries, the governments will levy a tax rate higher than that of a closed economy. Doing so can attract the flow of capital so that government can get more profit.

本研究以1999年至2005年中國上市公司財務資料，探討影響中國上市公司有效稅率之決定因素。本文的實證結果發現中國全體上市公司樣本的平均有效稅率僅達14.14%，遠低於中國稅法規定33%的名目稅率，顯示上市公司普遍享有區域及行業優渥的租稅優惠，實際所得稅負並不高。其中以海南市、上海市的有效稅率最低，而西部偏遠地區的有效稅率為最高，顯示區域間租稅負擔不均之現象。採掘業公司平均有效稅率高達25%，農林牧漁業及信息技術業的平均有效稅率在10%以下，也反映產業間的稅負分配受到政府產業發展的租稅獎勵政策之影響。此外，近年中國會計制度積極與國際會計準則趨同，企業依財會準則所計提之資產減損準備在稅務上不能列報扣除，使公司須繳納較高之有效稅率。 本研究也發現中國上市公司的股權結構與其有效稅率間具有顯著的相關性，國家持股比率較高者，租稅規劃意願低，有效稅率較高；而外資持股比率較高者及有發行B股或H股的公司，享有較多的租稅優惠及有較積極的租稅規劃傾向，有效稅率則較低。最後，本文也發現一些重要的中國企業特性、財稅差異項目與公司有效稅率關聯性之實證證據，中國上市公司的企業規模與有效稅率間，呈現正向關係，符合政治成本假說。獲利愈高的公司，其有效稅率也亦高。公司資本資產密度與財務槓桿的稅盾效果並不顯著，研究支出之投入與有效稅率呈負相關。營業費用比率較高之企業，受到稅法對於多項費用列報限額標準之影響，如罰款支出、贊助費、非公益、救濟性捐贈支出、廣告費、宣傳費、業務招待費以及職工薪金等，也有較高之有效稅率。企業獲配股利所得及依權益法認列的投資收益較多者，在稅法上毋須列入課稅所得之金額較高，故其有效稅率較低。上述中國上市公司的企業特性與有效稅率之關聯性，提供了中國企業經營的租稅成本深受中國會計、租稅制度、公司特性以及商業環境影響之實證證據。 / This study investigates the effects of Chinese accounting standards and tax system on the corporate effective tax rates (ETRs) of china listed companies. Despite that the statutory tax rate of China income tax law is 33%, we found the average ETR of China listed companies is only about 14.14% during our sample period spanning from 1999 to 2005, suggesting that most listed companies across various areas and industries may enjoy substantial tax incentives. The empirical results show that the companies in Shanghai and Hainan have lower average ETRs then those in other areas. Especially, the agriculture, forestry, herding, fishery industries and the information technology industries have the lowest average ETRs of below 10%, possibly due to that Chinese government provides substantial tax incentives for both industries. Further, to converge with the international accounting standards, China gradually phased-in the accounting for asset impairments in 1998 and 2001, requiring listed companies to recognize the impairment losses when the fair values of assets are below their book values. However, the unrealized asset impairment losses are not deductible in filing income tax returns, resulting in that firms reporting greater asset impairment losses in financial statements are more likely to bear higher ETRs, ceteris paribus. In addition, we also found there is a significant relationship between China companies’ ownership structure and corporate ETRs. Ceteris paribus, companies having greater state-shares are more likely to have greater ETRs while companies having greater foreign institute-shares and companies issuing B-shares or H-shares are more likely to have lower ETRs. Finally, we also documented evidence on the relationship between Chinese firms’ characteristics and corporate ETRs. Chinese large firms are more likely to have greater ETRs, supporing the political cost hypothesis. Due to several limitations on claiming operating expenses to be tax-deductible items, firms with greater operating expenses are more likely to have greater non-tax-deductible expenditures and hence tend to have higher ETRs. Finally, to alleviate double taxation on dividend income, dividend income received by the investment companies is tax-exempt to the extent that the invested companies have paid corporate income tax on the dividends distributed to the investment companies, and unrealized investment income accrued by the equity method is not taxable income to the investment companies until distributed to them. Consequently, firms having greater dividend income and investment income accrued by the equity method are more likely to have lower ETRs. Moreover we also find that the tax reform in 2002 make average ETRs increasing. The companies listing in Shenzhen Stock Exchange have lower average ETRs then those in Shanghai Stock Exchange. The results of this study provide empirical evidence on that the Chinese accounting standards and tax systems have a significant impact on the tax costs and distribution of tax burdens of Chinese listed companies.

本研究以2000年至2006年中國大陸上市公司之財務資料及股價資料，探討中國上市公司是否因租稅優惠而負擔隱含稅，及其負擔之隱含稅與有效稅率、股東權益稅前報酬率、市場結構及產業別之關係。實證結果顯示，中國大陸上市公司有效稅率之平均值遠低於其稅法上之名目稅率，顯示上市公司整體而言因稅法而享有租稅優惠，其中以農林漁牧業與信息技術業之有效稅率最低，反映中國扶植農業以及獎勵高科技產業之租稅政策。上市公司隱含稅率之平均值約為17.91%，顯示在中國大陸經濟成長率高之市場下，其上市公司仍須負擔隱含稅，且實證結果發現中國上市公司之有效稅率與隱含稅率呈顯著正向關係，即當有效稅率下降時，隱含稅率將會相對提高，呈現如Scholes and Wolfson(1992)所提出之隱含稅理論。 本研究實證結果亦發現，中國上市公司之股東權益稅前報酬率與隱含稅負間呈現顯著負向關係，即享受租稅優惠較多的公司，因負擔隱含稅成本，故整體報酬率未必高於享有較少租稅優惠的公司。非製造業公司之市場結構變數與隱含稅率間具有顯著關係性，即市場集中度越高時，廠商的市場支配力越大，也就越接近壟斷市場，造成該產業租稅優惠隱含稅負之負擔者多為消費者，而公司負擔之隱含稅則相對較低。 / This study uses financial and stock price data of the listed companies in China from 2000 to 2006, to examine if the listed companies have to bear implicit taxes because of tax preferential treatments, and to examine the relationship between implicit taxes and effective tax rates. The empirical results indicate that the average of ETRs of listed companies in China is lower than the statutory tax rate, indicating that overall listed Chinese companies have enjoyed substantial preferential tax treatments. The ETRs of the companies of agriculture and information technological industries are the lowest ones of all industries, reflecting China's tax policy aimed at developing agriculture and hi-tech industries. The average of implicit tax rates of listed companies in China is about 17.91%, indicating that listed companies in a high economics growth market, such as China, still have to bear implicit taxes. The empirical results show that implicit taxes are negatively related to ETRs, and the results support the implicit tax theory by Scholes and Wolfson(1992).The empirical results indicate the relationship between implicit tax and PEROEs is negatively, meaning the returns of tax-favored companies are less than tax-disfavored ones. The variables of market structures are significantly related to implicit tax, meaning the more market power the companies have, the less implicit tax they will bear. The empirical results of this study have implications for the government to further use tax incentives as a vehicle to stimulate economic development.