Lorrie Cranor and colleagues at the Carnegie Mellon University's Usable Privacy and Security Laboratory used a Carnegie Mellon shopping search engine called Privacy Finder for their study. The search engine automatically evaluates a Web site's privacy policies and displays the results on the search results page.

The researchers found people are more likely to buy from online merchants with good privacy policies. They were also willing to pay about 60 cents extra on a $15 purchase when buying from a site with a privacy policy they liked.

The study that included Assistant Professor Alessandro Acquisti and graduate students Janice Tsai and Serge Egelman is said to be the first to suggest people are willing pay a premium to protect their privacy when shopping online.

The data were to be presented Friday during an international meeting on informational security hosted by Carnegie Mellon.