The sovereign debt crisis has made it clear that central banking is more than keeping inflation low. Central banks are also responsible for financial stability. An essential tool in maintaining financial stability is provided by the capacity of the central bank to be the lender of last resort in...

I distinguish two types of macroeconomic models. The first type are top-down models in which some or all agents are capable of understanding the whole picture and use this superior information to determine their optimal plans. The second type are bottom-up models in which all agents experience...