Earnings season is in full swing with results expected from Caterpillar, Yahoo, Pfizer and Coca-Cola.

*  In its first quarterly earnings report since announcing the Microsoft search deal, Yahoo will provide important updates about its core display advertising business.

*  Heavyweight manufacturers United Technologies and Caterpillar report quarterly results.

*  Coca-Cola will shed light on the state of worldwide consumer spending when the world’s top soft-drink maker reports third-quarter results.

*  Top technology CEOs are speaking across the country. At the Web 2.0 conference in San Francisco, which runs through Thursday: Yahoo CEO Carol Bartz, Comcast CEO Brian Roberts, New York Times chief Arthur Sulzberger, General Electric CEO Jeff Immelt and Facebook COO Sheryl Sandberg. At the Executives Club of Chicago, Viacom CEO Philippe Dauman will speak and may address the state of the advertising business and Hewlett-Packard CEO Mark Hurd speaks at the Gartner Symposium/ITxpo in Florida.

*  In a big day for pharmaceuticals and healthcare companies, Pfizer, UnitedHealth Group, Gilead Sciences and Biogen report results.