empirical relationship is a natural law and attempt to exploit it, it
disappears. In particular the usefulness to private agents of the ratings caused regulators to decide to use them too (and destroy them) via Basel II. Regulations change things. Now ratings such as AAA are no longer mere
communicative acts whose value depends entirely on whether investors believe the. Now those three letters appear in a proposed regulatory framework. A bank that doesn't believe an instrument is worthy of an AAA rating can still choose to hold that instrument in order to keep its requried capital low. Any instrument that clears the AAA bar with room to spare has wasted safeness which is not being used leveraging up as much as possible."
Lisää aiheesta: http://angrybear.blogspot.com/2008/12/blame-basel-ii.html