本論文針對我國不動產整體稅制及合理性之探討，區分為每年繳納的持有稅及買賣移轉時課徵的交易稅，分別歸類爭議問題。 【持有稅】 地價稅： （一）稅基偏低。 （二）自用住宅用地認定標準過於寬鬆。 （三）減免範圍過於浮濫。。 房屋稅： （一）稅基偏低。 （二）非自住房屋稅率偏低。 （三）減免範圍過大。 （四）課稅範圍不合理。 豪宅稅： （一）無法抑制房價。 （二）「八大標準」難以客觀認定。 （三）加徵豪宅稅徒增稅制複雜性。 【交易稅】 奢侈稅： （一）成效不彰。 （二）未將預售屋轉讓契約及非都市土地納入課徵範圍。 （三）逃漏稅手法層出不窮。 （四）不論盈虧皆要繳納奢侈稅。 土地增值稅： （一）稅基以公告土地現值評價易形成漲價歸私。 （二）重購退稅以公告土地現值為比較基準有失公允。 （三）違反量能課稅。 財產交易所得稅制：稅制不符合公平正義。 契稅：契價與市價落差大。 印花稅：稅基偏低。 本論文參酌國際稅制、專家及學者探討不動產整體稅制及合理性爭議問題的見解後，提出下列建議： 地價稅： （一）縮短公告地價期間及調升公告地價以接近市價並調高「累進起點地價」與各級距累進稅率。 （二）修訂「自用住宅用地」優惠稅率之適用範圍。 （三）重新檢討減免範圍。 房屋稅： （一）調高房屋評定現值以貼近市價。 （二）重新修訂自住房屋定義採全國總歸戶並提高囤房稅率。 （三）縮減房屋稅減免範圍。 （四）不動產持有稅房地合一：房屋稅併入地價稅課徵「不動產稅」 豪宅稅： （一）調高公告地價並增加「多屋族」「富豪群」租稅負擔。 （二）重新檢視豪宅稅的課稅範圍。 （三）不動產持有稅房地合一：房屋稅與地價稅房地合一並以「實際成交價格」為認定標準。 奢侈稅： （一）加強打擊不動產投機交易動機。 （二）重新審定課稅標的。 （三）加強查緝逃漏奢侈稅。 （四）政府應朝實價課徵資本利得稅方向調整稅制。 土地增值稅： （一）調整土地公告現值接近市價。 （二）以實價登錄之成交價作為重購退稅衡量標準。 （三）不動產交易稅房地合一：土地增值稅與財產交易所得稅「房地合一」實價課稅。 財產交易所得稅：循序漸進按實價課稅。 契稅：以房地合一的交易價格實價課徵「取得不動產稅」且稅率應配合調降。 印花稅：依實價課稅且稅率應配合調降。

2010年台灣經濟成長率創新高，然貧富差距卻是台灣面臨最大問題之一，為避免大眾不良觀感，行政院乃針對高價服務、商品或交易，研議特種銷售稅，即通稱之「奢侈稅」，並於2011年通過與施行「特種貨物及勞務稅條例」。各國採行特種銷售稅種類繁多，課徵目的、稅率各有不同。究竟我國課徵奢侈稅制度與他國制度有何不同? 課徵奢侈稅效果為何?此為本研究主要動機。 本研究針對上述問題，採文獻分析與深度訪談法，進行深入的分析與探討。經實證分析發現：（1）主要國家課徵奢侈稅，課徵項目與目的各異。（2）解決不動產飆漲問題，多管齊下多重效果。（3）透過交易稅抑制投機，短空長多。（4）國際間相互依存，政府政策相互影響。（5）資訊透明化是決定市場機制能否發揮功效之關鍵之一。（6）不動產市場存在三種價格，阻礙不動產市場發展，更違反社會正義。（7）我國房價高漲主因財產稅稅負偏低。 / Although economic growth in Taiwan hit an all-time high in 2010, the gap between the rich and the poor has become one of Taiwan’s most serious issues. The Executive Yuan, in an effort to avoid negative public perceptions, held deliberations on a special sales tax for high-priced services, goods and trade, also commonly known as a “luxury tax”. The “Specifically Selected Goods and Services Tax Act” was sent to the Legislative Yuan for review 2011. Countries around the world have implemented many kinds of special sales tax. Such taxes differ in regard to their intended purpose and imposed rate. Exactly how does Taiwan’s imposed luxury tax differ from those of other countries? What has been the result of imposing the luxury tax in Taiwan? Finding out the answers to these two questions is the primary objective of this paper. This study conducted literature analysis and in-depth analys. Through the empirical analysis we found that: (1) The items and reasons for taxing should be considered separately. (2) In addressing the issue of soaring real estate prices, multi-pronged approaches bring multiple results. (3) Transaction taxes to control speculation result in short-term pain, but long-term gain. (4) Because of the interdependent nature of nations, the government policies of a given nation influence other nations. (5) information transparency is a key factor in deciding whether or not market mechanisms can be effectively leveraged. (6) the existence of three different prices in the real estate market is a barrier to the development of the market and, more importantly, violates the principles of social justice. (7) the main reason behind the rocketing price of housing in Taiwan is the low property tax burden.

國內近年來有許多文獻在進行特徵價格模型預測時，避免樣本中存在異常點會造成模型估計值產生偏差，會使用統計軟體進行異常點檢測，但皆是直接將檢測出的異常點刪除，未加以著墨探究這些異常點的特徵結構、成因及特色等。因此，本研究透過統計檢定方法，探討刪除異常點前後整體樣本的特徵結構變化，並以個別估價觀點加以探討住宅交易樣本異常點的成因與特色，藉此歸納出實價登錄資料未揭露的重要特徵，以及迴歸模型搜尋疑似申報不實案件之可行性。 透過敘述統計及樣本結構差異檢定結果發現，異常樣本的離散程度相對原始樣本與正常樣本較大，且經過刪除異常點的正常樣本特徵結構差異程度縮小；異常點的形成可能受到區位變數無法反映實際情況及樣本群聚程度影響，也可能因模型未納入某些重要的特徵變數，而使隱含該變數的樣本被判斷為異常點；異常樣本與正常樣本的成交總價、土地坪數、建物坪數、總樓層、所在樓層及屋齡等變數平均數、變異數及中位數有顯著差異。 藉由個案分析結果歸納，可能因異常個案的住宅屬性存在整幢大樓住商混合使用、特殊鄰居、附屬建物占比過高、高總價豪宅產品、都更效益、增建效益、裝潢效益、約定專用空間效益、樓層高度挑高、獨特視野景觀或特殊區位條件；外部環境存在鄰近嫌惡設施或迎毗設施；交易情況存在買方身分特殊之影響，但受限於實價登錄未要求登載並揭露這些特徵，故模型未考量這些因素對價格的影響，使得模型可能將隱含這些特徵的樣本判斷為異常點，並進而影響模型預測結果。另外也發現，實價登錄資料存在登載錯誤及價格申報不實的情況，且可能被模型判斷為異常點。 / Many literatures use statistics-way to detect outliers in preventing any extreme deviation in hedonic price model prediction. Nevertheless, deleting the outliers instead of investigation into the structures, causes and features. Hence, this thesis studies the feature structures variation of the sample before and after deleting the outliers and with the valuations by appraisers’ perspective to inquire into the factors and features of the outliers in residential transactions. Thereby to summarize the significant features that are not disclosed by real price registration and feasibility in searching the possible false declaration of price by regression. Through descriptive statistics and sample structural difference parametric and nonparametric test shows the discreteness level of singular (outliers only) samples is greater than the primary (outliers including) and normal (outliers deleting) samples and the feature structure variation lessened after deleting the outliers in normal samples. The formation of outliers may be influenced by location variable not able to reflect actual circumstances and level of clustering in samples. Maybe some significant variables are not subsumed into the model, which leads to the judgement of samples with this variable to be outliers. The mean, variance and median in total traded price, land size, building size, total floors, exact floor and house age of singular samples are notably different with normal ones. With the analysis of cases, the possible reasons may be residential and commercial mixed-use in building, peculiar neighbors, high proportion of accessory building, luxury houses, urban renewal benefits, building addition benefits, interior decoration benefits, agreed space benefits, high-ceiling benefits, unique view or location, YIMBY and NIMBY property in environment and special relationship between the buyer and seller. Nevertheless, due to the nondisclosure of these features in real price registration that the model does not take these into consideration. That leads to the judgement of samples with these features as outliers and affects the model prediction. Also the registration error and false declaration in price may also be judged as outliers.