Click fraud is currently a major topic in online advertising. Many argue that it presents a threat to the stability and viability of pay-per-click (PPC) advertising, the key revenue generator for both...

An analysis of web’s most popular 20,000 keywords by TopPayingKeywords.com, found that keyword prices dropped 3.0% from January 2005 to April 2005 from an average bid price of 58.9 cents to an average...