房屋預售制度是國內不動產業的一大特色，而長期以來國內對房價的研究皆著重於成屋價格，且大都以特徵價格法分析成屋價格屬性，對預售屋價格的形成及成屋與預售屋彼此價格相互影響一直缺乏深入的研究。造成政府管理及業者經營上的困擾，也直接威脅到購屋的權益，因此透過預售屋價格理論層次的探討，將有助於學術界對房屋預售制度的暸解。

由於房屋預售的交易標的為土地及房屋預售契約，而此約定於未來特定時間交貨之契約買賣形式，基本上即具有遠期交易與期貨的性質。因此本文利用儲存理論於無套利均衡的情形下，依序考慮有無不動產市場景氣變動與預售屋產品風險，來加以推演預售屋價格，最後導出預售屋訂價模式為成屋價格加成屋的持有成本，減預售屋的履約保證費用，加上預期景氣變動價差。模式中預售屋產品風險及市場景氣變動因素的考慮，為本研究學術上的主要貢獻。

進一步利用特徵價格方程式來固定品質，使成屋與預售屋在相同的基礎上比較，並藉由太平洋房屋所提供之民國77年?82年大台北都會區實際成交案例8885筆來試驗。發現期間預售屋每戶價格平均比成屋高出33．08萬，即就大台北都會區的房屋市場而言，購屋者於此期間選購成屋較有利、比較各年之預售屋與成屋價格，除77年之基差為負以外， 78年?82年的基差都大於零，其中基差變動的原因，可由本研究所建立之理論模式來加以詮釋。最後應用理論模式來分析房屋市場的基差，說明國內預售屋價格大多高於成屋價格的原因，並詮釋理論模式的政策意涵，與對購屋決策及建商經營的應用。

The pre-sales housing system in Taiwan is a quite unique method allowing home buyers to speculate on or purchase their houses. The prices of pre-sales houses have become a leading indicator of the housing cycle in the market. However, limited knowledge is availab1e regarding how and why pre-sales house prices are determined, or what is the relationshiP between the pre-sales and existing house prices.

　 Determining Whether the theories of forward or futures transactions can account for the pre-sales house pricing behavior is highly desired since one characteristic feature of the pre-sales syStem is its similarity to forwqrd of futures transactions.

In this study, an arbitrage perspective is used to discuss the difference (basis ) between pre-sales and existing house prices. Based on the storage theory, a pricing model suitable for pre-sales houses in Taiwan was established steP by step under the considerations of the presence of expected market changes, and the risk of product uncertainty in pre-sales houses.The price of pre-sales houses is equal to the price of existing houses on the transaction date plus the carry cost, and the price difference resulted from expected market changes minus the contract guarantee cost.

The established model was then used to analyze the 8885 actual transaction cases provided by the Pacific Rehouse during l988 and l993. We used hedonic price. theory to analyze the differences between pre-sales and existing house price. As far as the overall market is concerned, the analysis found that the difference between the pre-sales house price on the transaction date and the price of the existing house was NT$330,800/unit. The basis was positive in l988 and negative during l989 and l993. By the pricing modeL, we can explain the price of pre-sales houses was greater then that of existing housing in most cases. The results of our research also can be applied to the real estate policy and the decision of purchasing house.