Rating, Kapitalmarktsignale und Risikomanagement: Reformansätze nach der Transatlantischen Bankenkrise

The ratings of leading rating agencies are crucial signals for economic agents in capital markets, namely with respect to creditworthiness of companies, banks and governments which place bonds in the market. The increasing role of securitization of loans has reinforced the role of ratings. The analysis highlights – based on portfolio theory – the role of ratings with respect to macro-prudential aspects, here some well known distortion problems are taken into account, too. As regards alternative modes of rating it is pointed out that with respect to welfare aspects rating in the form of a public good is superior to an alternative approach which organizes ratings on the basis of providing a private good. For the first time a macro model of an open economy which includes ratings is presented here. Moreover, the focus is on potential G-20 reforms and policy approaches in the EU.