One of the most revealing contradictions in the results of the survey is that those who have taken steps to try to avoid observation by others and those who have taken more general steps to be anonymous are more likely than others to have personal information posted online, the researchers said.
Internet users surveyed said they have a photo of themselves online (66 percent), while about half of those polled said their birth date was available online. A minority said that their email address, home address, mobile number, or political affiliation was available.
A majority of Web users polled, 66 percent, said they think current privacy laws are not good enough to provide reasonable protections for people's privacy on their online activities.
"Interestingly, there are not noteworthy differences in answers to this question associated with political or partisan points of view. Tea Party supporters, conservative Republicans, self-described moderates, and liberal Democrats are not statistically significantly different in their answers," the researchers wrote.
Loek is Amsterdam Correspondent and covers online privacy, intellectual property, open-source and online payment issues for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to email@example.com.