If rating agencies add no new information to markets, their actions are not a public policy concern. But as rating changes may be anticipated, testing whether ratings add value is not straightforward. This paper argues that ratings and spreads are both noisy signals of fundamentals and suggest...

"This paper measures the effects of the risks associated with the war in Iraq on various U.S. financial variables using a heteroskedasticity-based estimation technique. The results indicate that increases in what we call the "war risk" factor caused declines in Treasury yields and equity prices,...