The study looked at how changes in credit ratings affect government bond yields in Europe. They found that negative rating announcements led to higher bond yields. These announcements were not expected in the short term, but there was a back-and-forth relationship between ratings and yields within a couple of weeks. The effects of these announcements spread to other European countries, especially in the Eurozone, and lower-rated countries had an impact on higher-rated ones. Countries that were recently downgraded experienced lasting effects on their bond yields.