House Price Dynamics and Mortgage Default Risk

Abstract

We find that house price momentum, defined as positive autocorrelation in aggregate house price changes, is stronger and house price change volatility is weaker when and where mortgage default risk at origination is higher. These facts appear widely, both geographically and temporally, and are difficult to reconcile with existing theories of house price dynamics. To explain these facts, we introduce a model in which lenders use valuations that incorporate information relatively slowly. In equilibrium, prices reflect the valuations used by lenders most when default risk is highest. Our model jointly explains the observed relations between default risk, momentum, and volatility.

Keywords: House prices, mortgage default risk, momentum, volatility

JEL Classification: G11, G12, G51, R30