4Kling R,Lee Y,Frankel M,et al.Assessing Anonymous Communication on the Internet:Policy Deliberations[J].Information Society,1999(2):79-90.
5Frey D.Different Levels of Cognitive Dissonance,Information Seeking and Information Avoidance[J].Journal of Personality and Social Psychelogy,1982(6):1175-1183.
6Euroupe commission Public Opinion.http://ec.eu-ropa.eu/public_opinion/index_en.htm.
7American Public Opinion Index.Louisville.KY:Opinion Research Service,1981-ongoing.
8Elizabeth Hahn Hastings and Philip K.Hastings.Index to International Public Opinion(1986-1987).West-port,CT:Greenwood Press.
10Kms-M,Hovy E."Determining the sentiment of o-pinions." In Proc.of COLING-04,The Conference on Com-putational Linguistics (COLING-2004).Geneva,Switzer-land.2004.1367-1373.