摘要：The paper by Heider and Hoerova (2009) is ambitious. It studies the interaction between secured interbank lending, unsecured interbank lending, and banks’ portfolio choices. It is motivated by a puzzling empirical observation, namely the “decoupling of secured and unsecured lending rates” in the Great Financial Crisis of 2007–09. The observation made by Heider and Hoerova is that on August 9, 2007, not only did secured three-month interbank rates start to exhibit historically unprecedented discounts to unsecured rates, but the time-series behavior of both rates began to diverge as never before. Furthermore, the discount of secured interbank rates fluctuated more strongly in the United States than in the euro area. While the evidence consists of only two plots of time series, it is obvious without any further econometric analysis that the phenomenon is there and is significant.
