2011年政府開徵奢侈稅,其政策設計隱含了「短期重複交易將造成房價上漲」的假設,但國內目前未有針對兩者關連性進行研究之實證文獻,因此本研究欲以實證的方式分析2007年至2009年台北市的不動產交易資料,了解房屋的短期重複交易對周圍房屋交易價格之影響為何。 本研究採用特徵價格模型進行研究,並透過兩階段的研究設計,一步一步檢驗短期重複交易行為對周圍房屋交易價格的影響。研究結果發現:(一)短期重複交易行為對周圍房屋交易價格所產生的影響,須視區域及該短期重複交易房屋的特性而定,無法一概而論。(二)在文山區與士林區,短期重複交易行為對周圍房屋交易價格會有正向顯著的影響,可能的原因是這兩個行政區有最多的短期重複交易房屋,故帶動周圍房價的效果也較大。(三)月平均低漲幅的短期重複交易房屋對於周圍房屋之交易價格有顯著正向的影響。(四)月平均高漲幅以及坪數小於15坪之短期重複交易房屋對於周圍房屋之交易價格有顯著負向的影響,推測可能與短期重複交易者之習性及樣本期間限制有關,或者是因為這類短期重複交易樣本的所在地點本就房價較低。 本研究結果對於公共政策的啟示是,政策制定者若想要透過抑制短期重複交易的政策來影響房價,於設計政策時須將區域特性和短期重複交易房屋之特性也一併考慮,否則可能效果不彰。此外,以持有期間來判斷一筆房屋交易的動機是否為投機仍有其限制,故或許未來政策制定者對於房屋投機行為能夠有更細緻的操作化定義。
In 2011, the government levied Luxury Tax, and the policy design implied that house flipping caused the rise of house prices. However, for the time being, there is no empirical research indicating a correlation between “house flipping” and “house prices”. Therefore, the study uses the house sales data in Taipei from 2007 to 2009 to analyze what the flipping’s effects on the prices of neighboring houses in Taipei. Through the two-steps research design, the study uses hedonic model to empirically determine if the houses that have been previously flipped (hereinafter referred to as “Flip”) will affect the prices of neighboring houses which was not flipped (hereinafter referred to as “Non-Flip”. The findings show that (1) the flipping’s effects on the prices of neighboring houses depend on the characters of each regions and the characters of Flips themselves. (2) the flipping’s effects on the prices of neighboring houses are positive in Wenshan and Shilin district. (3) the flipping’s effects on the prices of neighboring houses will be positive if the monthly growth of the Flip’s prices are low. (4) the flipping’s effects on the prices of neighboring houses will be negative if the monthly growth of the Flip’s prices are low or the area is less than 49.65 square meters. The implication of these findings is that if policy makers want to prevent the house prices from rising by reducing the number of flippers, then they should take the characters of each region and the characters of Flips themselves into consideration. Besides, because there are limitations of using the “holding period” to predict the buyers’ motivations, we hope that the policy makers and researchers could develop a better operational definition of “property speculation” in the future.