Abbasi, Ahmed, and Hsinchun Chen. "Analysis of affect intensities in extremist group forums." Terrorism informatics: Knowledge management and data mining for homeland security. Boston, MA: Springer US, 2008. 285-307.

This study explores the role of affect analysis in understanding perceptions and decision-making within extremist groups. By constructing a probabilistic affect lexicon, the researchers analyze postings from U.S. supremacist and Middle Eastern extremist forums to measure the presence of violence and hate. Their evaluation across 16 forums reveals that Middle Eastern groups exhibit significantly higher violence intensity compared to U.S. groups, with a notable correlation between hate and violence in the Middle Eastern content.