In a competitive information market, a single information source can only dominate other sources individually, not collectively. We explore whether earnings announcements constitute such a dominant source using Ball and Shivakumar's (2008) [How much new information is there in earnings?, <italic>Journal...</italic>

We study the determinants and market impact of sell-side debt research. Analyzing a sample of 5920 debt reports published by 15 brokerage firms from 1999 to 2004, we document that companies with a higher probability of financial distress, lower market-to-book ratio, larger debt, and higher...