租金與住宅使用成本關係之再探討：實質選擇權觀點

Re-discussion of the Relationship between Rent and Housing User Cost—Real Option Viewpoint

本文加入實質選擇權價值，建構租買選擇模型，以檢驗租金與住宅使用成本的長短期關係，並探討當市場狀態改變時，兩者關係的變化、及其如何影響租買的決策。結果發現，在考慮實質賣權後，租金與住宅使用成本的均衡關係，是存在的，不同於以往實證文獻所示。而且在2007 Q3前後，兩者關係，顯著不同，佐證次貸危機造成美國房市結構性的變化。當兩者處於均衡狀態，若賣權價值上升，租金會下跌，消費者傾向選擇購屋，導致租金下降；當脫離均衡狀態時，若賣權價值上升，住宅使用成本會下跌，消費者仍會擔心房價泡沫化的問題，而傾向選擇租屋或提前將房屋出售，導致住宅使用成本下降。研究結果，除充實類似領域文獻、深入瞭解租金與住宅使用成本的動態關係外，更有助於相關議題之探討、政府有關單位制定房地產政策之參考依據、及促進合理房價之形成。

We add real option value in housing tenure choice model to examine the relationship between rents and housing user costs as well as the decision making of tenure choices with and without structural break. Unlike previous literature, we find that there exists long-run equilibrium between user costs and rents after considering real options value. A clear structural break in 2007 Q3 or after subprime mortgage crisis also changed the relationship between the two mentioned above. In equilibrium state, we find that real option value exhibits a negative impact on rents and buying a house is preferred over renting; In the other state, the negative impact is on housing user costs and renting is preferred over buying a house. Our findings can help better understand the decision making of tenure choice, promote the formation of reasonable housing prices, and shed light on sound development of the real estate market in Taiwan.