公佈降雨淹水模擬地圖對淹水區與其鄰近地區住宅價格之影響

Impacts of the Announcement of the Rainfall-induced Flood Simulation Map on Flood Area and Neighborhood Housing Prices

本研究探討公佈降雨淹水模擬圖對淹水區與其鄰近地區住宅價格之影響。我們使用實價登錄網站2014年10月到2017年7月的住宅價格資料和水利處公佈的降雨淹水模擬地圖，運用分量迴歸和空間分量迴歸，並結合差異中之差異法進行估計。在考慮空間自我相關的情況下，公佈降雨淹水模擬地圖後，位於淹水區內之住宅價格會下降約13.5%。進一步考慮公告效果對不同價位住宅的影響，公佈後且位於淹水區內，於低價位、中低價位、中價位、中高價位和高價位住宅價格分別會下降約17.0%、8.9%、11.6%、17.0%和19.3%。公佈後且位於淹水區之鄰近地區，於高價位住宅價格則會下降約5.4%。

This study aims to examine the impact of releasing the rainfall-induced flood simulation map on housing prices in locations deemed to be flood areas and their neighboring areas. Quantile and spatial quantile regressions, as well as the difference-in-differences method, were utilized to analyze the data from a real housing price website that spanned the period from October 2014 to July 2017 and the rainfall-induced flood simulation map released by the Hydraulic Engineering Office. After taking into account spatial autocorrelation, the release of the rainfall-induced flood simulation map was found to have led to a decline of approximately 13.5% in the housing prices of locations in flood areas. A further examination of the announcement’s effects across different housing price ranges revealed that housing prices in the low, mid-low, mid, mid-high, and high price ranges of locations in flood areas fell by 17.0%, 8.9%, 11.6%, 17.0%, and 19.3%, respectively. The release of the rainfall-induced flood simulation map was found to have led to a decline of approximately 5.4% in the high price range of housing in locations neighboring flood areas.