An expansion in mortgage credit to subprime borrowers is widely believed to have been a principal driver of the 2002-2006 U.S. house price boom. By contrast, this paper documents a robust, negative correlation between the growth in the share of purchase mortgages to subprime borrowers and house price appreciation at the county-level during this time. Using two different instrumental variables approaches, we also establish causal evidence that house price appreciation lowered the share of purchase loans to subprime borrowers. Further analysis using micro-level credit bureau data shows that higher house price appreciation reduced the transition rate into first-time homeownership for subprime individuals. Finally, the paper documents that subprime borrowers did not play a significant role in the increased speculative activity and underwriting fraud that the literature has linked directly to the housing boom. Taken together, these results are more consistent with subprime borrowers being priced out of housing boom markets rather than inflating prices in those markets.

人们普遍认为，向次级抵押贷款人提供抵押贷款的扩张是2002-2006年美国房价暴涨的主要驱动力。相比之下，本文证明了在这段时间内，次级抵押贷款购买者抵押所占份额的增长与县一级的房价升值之间存在强烈的负相关关系。使用两种不同的工具变量方法，我们还建立了因果证据，即房价上涨降低了次级抵押贷款购买贷款的份额。使用微型信贷机构的数据进行的进一步分析表明，较高的房价升值降低了次贷个人向首次购房的过渡率。最后，该文件证明，次贷者在投机活动和承销欺诈的增加中没有发挥重要作用，而文献中这些直接与住房繁荣有关。两者合计，这些结果更符合次级抵押贷款者在房地产繁荣市场之外的定价，而不是夸大这些市场的价格。