金融機構為了滿足新版巴塞爾協定必須每年對不動產抵押擔保品進行重新鑑價的規定，採用房價指數來進行資產重新估計。然而，觀察現今發佈的國泰與信義房價指數，發現兩指數走勢及變動幅度上，皆存在相當大的分歧。 因此，本研究採用西元2005年至2007年間台北市十二行政區房屋之實際成交價格為研究範圍，建立特徵價格模型，並結合市場比較法中期日修正概念，利用房價指數進行調整，再依Hit Rate 及MAPE準則評估整體表現。為了避免樣本誤差對於實證結果的干擾，透過隨機抽樣三十次進行重複實驗，測試模型穩定性及估計精確度，最後，採用兩成對樣本T檢定，檢定房價指數是否有助於不動產標的重新估計，並分析兩房價指數何者較能確切的反應當前市價。 實證結果發現:(1)使用房價指數調整之估值正負誤差在10%及20%以內的命中率以及MAPE皆有顯著改善，這說明現今發佈之房價指數具備反映市場實際價值的能力，仍有繼續編制及發佈的必要。(2)經由比較並分析兩房價指數結果可知，以國泰房價指數調整之估值在10%及20%以內的命中率，以及MAPE指標上，皆通過顯著性檢定。而使用信義房價指數調整之估值表現僅在10%及20%以內的命中率通過成對T檢定，故可知國泰房價指數較能充分地扮演著揭露不動產市場訊息的角色。

過往研究編製房價指數時多在品質固定或控制下，觀察房價的波動趨勢，對於住宅品質的改變如何影響房價則少有說明。而住宅品質為生活品質的一部分，亦為購屋者消費或投資時所關心，然住宅價格與品質間存在何種關係並不清楚，若認為高價格的住宅即代表高品質，則可能存在做出錯誤決策的風險。 本研究利用特徵價格法，探討台北市與台北縣於2000年至2009年間，新推個案與中古屋交易市場住宅品質的改變與房價關係。實證結果發現台北市的標準住宅的品質因改變程度較新北市小，故其對房價指數的波動不如在新北市中明顯。另外，台北市新推個案與中古屋住宅的區位條件無明顯衰退之情形，產品品質亦無明顯的提升；新北市新推個案與中古屋住宅的區位條件皆呈現衰退現象，但新推個案的產品品質則有提升趨勢，而中古屋住宅則是下降的趨勢。 最後，分析住宅價格與品質間的相關性，實證結果發現，新北市的新推個案住宅與台北市的中古屋住宅存在正相關，顯示在此兩種次市場中，支出更多價格購屋亦獲得更好的住宅品質。 / Most of the existing housing price indexes empirical studies are under quality-constant or quality-control, because housing quality change is difficult to measure. In these cases, one does not concerned about that price index, if one interested in consumption or investment. We use hedonic price model discusses the relationship of housing price and housing quality about new housing projects and transacted house during 2000 and 2009 in Taipei City and New-Taipei City. The empirical results show that due to degree of change in housing quality of representative house in Taipei City smaller than in New-Taipei City, so the volatility of the price index was significantly better in New-Taipei City. In addition, the Taipei City housing “location condition” no recession , and no obvious improvement of “structural quality”; New housing projects and transacted house in New-Taipei City, respectively, increase and decline, but the location condition are present recession. Furthermore, we find that there is positive correlation between housing price and quality in Taipei City’s transacted house market and New-Taipei City’s new housing projects market. In these two sub-markets, consumer spending more housing prices and get better housing quality.

國內有許多以不同資料、次市場劃分以及控制品質的方法編製房地產相關價格指數，提供不同的價格資訊，然而編製的過程可能產生偏誤，影響價格指數之準確性，導致房價指數變動與市場訊息不符，因此各種相關房價指數之市場代表性仍有待釐清。 本文首先觀察目前市場較常使用之信義房價指數(中古屋)及國泰房地產指數(預售屋及新成屋)，發現近年來信義房價指數無法適當反應房地產市場景氣繁榮的情形。此二房價指數領先落後的關係亦不符合相關理論及過去實證，因此認為此二房價指數長期趨勢受到編製資料及估計方法上的偏誤所影響。接著利用政府(房地產交易價格簡訊)及業者(台灣不動產成交行情公報)資料以特徵價格法重新建立台北市及台北縣中古屋房價指數，並與信義房價指數作比較，結果顯示本文建立之中古屋房價指數相對於信義房價指數較符合市場變動與相關訊息。最後，為求未來房地產資訊之應用，將過去相關房價指數研究成果與本文建立之房價指數整合，並驗證台北市國泰房地產指數領先整合中古屋房價指數一季，台北縣國泰房地產指數領先整合中古屋房價指數二季，顯示此台北都會區的中古屋及預售屋房價指數相互間的關係符合相關理論推導與過去實證結果。 / There are many real-estate related price indices established in various formation of datum, submarkets and modeling, providing different kinds of price information. But the process itself may be a victim of error, hence affecting the precision of price indices and cause discrepancy between price indices’ variation and correlative market information, therefore the representativeness of real-estate related price indices must be clarified. In this study, we observe the commonly used Sinyi Housing Price Index (existing housing) and Cathay Real-Estate Price Index(pre-sales and new housing), and discovered that Sinyi Housing Price Index is incapable of reflecting the recent boom in the real-estate market. The Granger Causality test result of these two housing price indices(HPI) is inconsequent to relevant theory and empirical studies, therefore attribute this to the error within the establishment of HPI. Then, we reestablish existing housing HPI of Taipei city and Taipei county by using government and enterprise organized data. In comparison to Sinyi Housing Price Index, our newly established HPI cohere with correlative market information. And last, for future application of real-estate market information, we integrate empirical studies in the past with ours and examine its lead-lag relation with Cathay Real-Estate Price Index. The Granger Causality test result corresponds to relevant theory and empirical studies, furthermore, we found that the time-gap between Cathay Real-Estate Price Index and the Integrated existing housing HPI in Taipei city is 1-season, and 2-season in Taipei county.