We examine the impact of household mortgages on house prices. Using biannual data on Italian cities for the years 2003-2015, we build an exogenous and fully data-driven indicator of mortgage supply stances and use it as an instrument for actual extended mortgages. Our results indicate that mortgages have a positive and significant causal effect on house prices, with an estimated elasticity of around 0.1. The estimated effect is larger during the expansionary phase of the housing cycle. We also find evidence of significant spatial heterogeneity: mortgages push real estate values higher in cities where the housing supply curve is less elastic or households are more dependent on external finance.

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房价如何对抵押贷款供应做出反应？

我们研究了家庭抵押贷款对房价的影响。我们使用 2003 年至 2015 年意大利城市的半年数据，构建了一个外生的、完全由数据驱动的抵押贷款供应状况指标，并将其用作实际延长抵押贷款的工具。我们的结果表明，抵押贷款对房价具有积极且显着的因果效应，估计弹性约为 0.1。在住房周期的扩张阶段，估计的影响更大。我们还发现了显着空间异质性的证据：在住房供应曲线弹性较小或家庭更依赖外部融资的城市，抵押贷款推高了房地产价值。