房地產業的活動被一般人認為是「火車頭產業」，探究這種未經學術嚴謹定義的說法，涵意概有兩層：其一是認為房地產業有極大的「向後關聯」效果，將可帶動相關總體經濟產業的發展。另一層涵意是指房地產業既然有帶動總體經濟繁榮成長的功能，也就意味著房地產業活動所構成的房地產景氣具有領先總體經濟景氣的特質，而為一般景氣昇沉的預期訊號。惟這種說法似乎與現實情況不合：現總體經濟景氣已有復甦跡象，但房地產業卻相對的毫無起色，因此本研究從「房地產業對總體經濟活動之影響分析」、「房地產景氣與總體經濟景氣在時間上領先、同時、落後關係之探討」兩部份，分別以較嚴謹的「產業關聯分析法」與「景氣綜合指標分析法」，來探討該說法的正確性及政策等含意，獲得「尚無充份的證據支持房地產業是火車頭產業」的結論。

　　有關政策涵義方面：房地產業的向後關聯效果不強，意味著政府如意圖以房地產業為振興經濟的逆循環政策應改變至回歸市場機制的調控，而不應有太多的政策介入。政府不必因總體經濟的不景氣而企圖刺激房地產景氣；亦無須強調總體景氣過熱而打壓房地產景氣。至於「房地產景氣與總體經濟景氣在時間上領先、同時、落後關係」部份，不論房地產綜合、各層面、基準循環指標之景氣與總體經濟綜合、構成房地產綜合景氣重要指標時間上關係比較中，我們有足夠的證據認為「房地產景氣落後總體經濟景氣」。在預測上的涵意是若干重要總體經濟指標可以用來預測房地產景氣未來的走勢。

　　The fluctuation in the real estate market is of long-standing, and has evoked much discussion, particularly how the real estate activities and cycles are related to macroeconomics has been an important issue drawing tremendous attention in Taiwan. This research contains two parts : in the first part, we have applied the method of lnput-Output(I/O) analysis to identic the backward linkage of the real estate sector. In the second part, we try to use the method of composite indexes of business cycle for real estate cycle indicators, including individual activities, four different stages of real estate life cycle -- investment, construction, transaction, and utilization, to clarify the " timing " relationship between business cycle and real estate cycle.

　　Based on the economic analysis, the results of this research are following :

　　1. We have not found strong evidence supporting the important backward linkage of the real estate sector. It means, in the view of using real estate activities for pushing macroeconomics, the government should not intervene the activities of real estate industry to market mechanism due to the effect of real estate activities contribute little feedback to macroeconomics.

　　2. Our investigation reveals the macro-variables, such as GDP, M2, the index of stock market, CPI, composite index etc. , tend to be leading indicators of real estate activities over twelve months approximately. This means, in the view of forecasting, we can use certain macro-variables to forecast the trend of real estate cycle in the fliture.

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