Two Extensive Margins of Credit and Loan‐to‐Value Policies
分析了抵押贷款市场、住房选择、异质性主体和违约的模型，发现最优贷款价值比上限需平衡购房可及性与违约负外部性，且购房可负担性会引入顺周期监管因素。
We analyze a model of mortgage markets, housing tenure choice, heterogeneous agents, and default with closed form solutions. We uncover new insights which may inspire empirical work, and we ground already established insights in a series of tractable expressions. Then we study optimal loan‐to‐value (LTV) regulation and show that the choice of an LTV cap should balance the opposing forces of access to homeownership and the negative externalities associated with default. Homeownership affordability concerns induce procyclical elements into optimal regulation which attenuate the countercyclical regulation justified by the negative default externalities.