Anonymity, for one thing. According to a September Pew poll, a quarter of Internet users have posted comments anonymously. As the age of a user decreases, his reluctance to link a real name with an online remark increases; forty per cent of people in the eighteen-to-twenty-nine-year-old demographic have posted anonymously. One of the most common critiques of online comments cites a disconnect between the commenters identity and what he is saying, a phenomenon that the psychologist John Suler memorably termed the online disinhibition effect. The theory is that the moment you shed your identity the usual constraints on your behavior go, tooor, to rearticulate the 1993 Peter Steiner cartoon, on the Internet, nobody knows youre not a dog. When Arthur Santana, a communications professor at the University of Houston, analyzed nine hundred randomly chosen user comments on articles about immigration, half from newspapers that allowed anonymous postings, such as the Los Angeles Times and the Houston Chronicle, and half from ones that didnt, including USA Today and the Wall Street Journal, he discovered that anonymity made a perceptible difference: a full fifty-three per cent of anonymous commenters were uncivil, as opposed to twenty-nine per cent of registered, non-anonymous commenters. Anonymity, Santana concluded, encouraged incivility.
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