Date Added: Jul 2010
Current studies on spam evolution usually extract evolution patterns and trends by analyzing historical spam message corpora. In this paper, the authors propose a novel methodology that incorporates spam filters to the spam trend analysis, as they are the agents that may force spammers to change their tactics. Moreover, filters also evolve over time and different filter releases present different characteristics, providing different views of the spams. They considered both outdated and recent releases of the Open Source SpamAssassin filter and applied their criteria on spams collected from the Spam Archive dataset, a dataset that contains spams collected from 1998 to 2010. When they compare the effectiveness of old and recent filters over old and recent spams, spam trends naturally emerge.