We analyze financial support for the entrepreneurial sector. State support can raise welfare by relaxing financial constraints, but it can also reduce lending standards if entrepreneurs substitute public sources of collateral for their own assets, if it encourages excessive entrepreneurial...

We analyze optimal monetary policy in a sticky pricemodel where the central bank supplies money outrightvia asset purchases and lends money temporarily againstcollateral. The terms of central bank lending affect ra-tioning of money and impact on macroeconomic aggre-gates. The central bank can...

We present a simple macroeconomic model with open market operations that allows examining the effects of quantitative and credit easing. The central bank controls the policy rate, i.e. the price of money in open market operations, as well as the amount and the type of assets that are accepted as...

This paper uses the market-standard Gaussian copula model to show that fair spreads on CDO tranches are much higher than fair spreads on similarly-rated corporate bonds. It implies that credit ratings are not sufficient for pricing, which is surprising given their central role in structured...

Does demand for safety create instability ? Secured (repo) funding can be made so safe that it never runs, but shifts risk to unsecured creditors. We show that this triggers more frequent runs by unsecured creditors, even in the absence of fundamental risk. This effect is separate from the...

This paper presents a simple equilibrium model in which collateralized credit emerges endogenously. Just like in repos, individuals cannot commit to the use of collateral as a guarantee of repayment, and both lenders and borrowers have incentives to renege. Our theory provides a micro-foundation...

This paper presents a simple and tractable equilibrium model of repos, where collateralized credit emerges under limited commitment. We show that even if there is no time variation in fundamentals, repo markets can fluctuate endogenously over time. In our theory, repo market fragilities are...