A computer scientist at Columbia University found that every single person surveyed in a study about Facebook usage was sharing something they wished to hide, or hiding something they wished to share -- a finding that highlights the shortcomings of the online social network's privacy settings, according to his research.

The study is believed to be the first that considers the privacy intentions of users of the popular network, which has more than 600 million members worldwide, and attempts to reconcile users intentions with how their information is actually displayed on the site.

Steven M. Bellovin, who as a graduate student helped develop the USENET internet discussion board system more than three decades ago, reviewed his study during a talk to students at the University of Maryland School of Law today in Baltimore.

"If you think it should be kept private, have you succeeded in doing so?" Bellovin posited to the crowd.

Bellovin said that most people indicated in his study that they cared about privacy, and that media coverage of privacy concerns with Facebook had made them pay more attention to the issue. But a majority of users indicated that they can not or will not fix errors in their privacy settings, he said.

"The overwhelming majority of people have given up," said Bellovin. "That, to us, is a fairly damning statement on the user interface."

The study was limited to surveying 65 Columbia University students, who were recruited on campus, and completed by using a customized Facebook application.

Below, Bellovin, left, accompanied by UMD law professor Danielle Citron.