作者融合投資報酬率的概念與Hicks(1946)與Lange(1948)的期望價格彈性理論，以各州的房貸利率、 租金、 房價，將(一)對房價的不理性預期量化；接著以各州的放款人員就業人數，除以各州的貸款審核人員的就業人數， 將(二)貸款審核標準量化； 最後，以1992-2008的四次總統大選結果將全美50州編碼為1、0、或－1，作為政治傾向的量化變項。 我們的統計結果告訴我們，房價在2000-2011在全美50州的不均勻變化是由於各州對房價的不理性預期的不同、以及各州對房價前三年變動的認知不同所導致。貸款審核標準雖然可以解釋此一期間的房價變動，然而解釋的強度並不是很強大。政治傾向對房價變動沒有一定的影響，這也駁斥了民主黨州的泡沫程度比共和黨州的來得大這種說法。 US housing bubble varies in the 50 states in terms of housing price. Between 2000-2007, housing price skyrocketed in 7 states, with annual growth rate between 11-13%, whereas the interior states grew at 2-5% annually. Between 2007-2011, housing price plummeted in 4 states with annual falling rate of 9-11%, whereas the interior states fell only 1-4% annually. Moreover, housing prices in North Dakota rose by 11% in the plummeting years of 2007-2011. Literature on housing bubbles generally ignored the regional disparity which we are interested in and therefore set forth our research question as: what has driven the uneven distribution of the US housing bubble in terms of housing price between 2000-2011? We firstly assume that the regional disparity was caused by the variances of the following three variables:(1)irrational expectation on housing prices;(2)mortgage underwriting standards;(3)political preferences. In order to compare and contrast the above three variables, we need to quantify them in the first place. We merged the notion of capital gains with the theory of expected price elasticity derived from Hick(1946) and Lange(1949) into a single framework and thus quantified (1)irrational expectation on housing prices; we then divided the employees who issue loans by the employees who check and authorize the loans, and got our quantified(2)mortgage underwriting standards; thirdly, we coded the 50 states political preferences as 1,0, or－1, according to their voting records between the 1992-2008 presidential elections. Our panel data regression informs us that the uneven fluctuation of housing prices in the 50 states between 2000-2011 is due to differences in irrational expectation on housing prices among states, as well as differences in recognition of the movements of housing prices in the past three years . Mortgage underwriting standards does explain the movement of housing prices in 2000-2011, however the effect is not so large. Political preferences do not impact housing prices at all; Democratic states do not have more severe bubbles than the Republican states.
