Does the mere presence of big banks affect macroeconomic outcomes? Gabaix (2011) shows that idosyncratic shocks can have aggregate effects if the distribution of firm sizes in manufacturing follows a power law distribution. Our contribution is two-fold. First, we expand the theory of granularity...

This paper analyzes the determinants of the interest margin of German banks over the period 1995-2007, explicitly addressing differences among different bank groups. We use three empirical models to focus on the following aspects: the time evolution of the interest margin, the average...

One explanation for the poor performance of regulation in the recent financial crisis is that regulators had been captured by the financial sector. We present a micro-founded model with rational agents in which banks may capture regulators due to their high degree of sophistication. Banks can...

Business cycles imply liquidity risks for banks. This paper explores how these risks influence bank lending over the cycle. With forward-looking banks, lending cycles, credit booms and busts, or suppressed and highly fragile bank systems can emerge, depending on the magnitude of liquidity risks....

The ex ante theory of collateral states that better informed lenders, such as informal lenders, rely less on collateral. We test this by contrasting the use of collateral between formal and informal lenders in the same market. Indeed, formal lenders rely more often on collateral, controlling for...