What if opting out of data collection were easy?

New study shows dearth of privacy opt-out choices and offers solution to empower users to readily identify choices often buried deep in the text of privacy policies

Daniel Tkacik

Jan 12, 2021

While many websites offer users choices to opt out of some of their data collection and use practices, most of these choices are buried deep in the text of long, jargon-filled privacy policies and are never seen by users.

Recent work by researchers in Carnegie Mellon University CyLab has shown that it is possible to use machine learning techniques to automatically extract and classify some of these opt-out choices. The results of this research were presented at the 2020 Web Conference.

The study also introduces Opt-Out Easy, a novel browser plug-in that automatically extracts opt-out choices from privacy policies and presents them to users in a friendly, easy-to-use manner. Opt-Out Easy is available for free download now.

“Different privacy regulations grant users the right to revoke how their data can be used by companies,” says CyLab’s Norman Sadeh, a professor in the School of Computer Science, and the principal investigator on the study. “But as it stands, most websites don’t offer users easy and practical access to these choices, effectively depriving them of these rights.”

In their study, Sadeh’s team trained a machine learning algorithm to scan privacy policies and identify language and links related to opt-out choices. They ran their algorithm on 7,000 of the most popular websites and found that over 3,600 of them (~ 51 percent) contain zero opt-out choices. A little over 800 (~ 11 percent) provide just one opt-out hyperlink.

“Our study aimed to provide an in-depth overview of whether popular websites allowed users the ability to opt out of some data collection and use practices,” Sadeh says. “In addition, we wanted to also develop a practical solution to help users access opt-out choices made available to them when such choices are present.”

Most websites don’t offer users easy and practical access to these choices.

Norman Sadeh, professor, School of Computer Science

To help make opt-out choices more accessible to users, the team developed a browser extension called Opt-Out Easy in collaboration with the University of Michigan School of Information. The extension is now available to Chrome users.

By clicking on the plugin’s icon, users are presented with opt-out links found in the privacy policy of the website they are currently visiting, allowing them to, for example, opt out of analytics or limit marketing emails.

Finally, the team conducted a usability evaluation of Opt-Out Easy, focusing on its effectiveness, efficiency, and overall user satisfaction. The users who took part in the evaluation generally found the browser extension easy to use, and strongly agreed that the various types of opt-outs provided by the plugin were useful.

“Our team put in hard work to come up with a browser extension that makes the most of opt-out choices available on a given website,” Sadeh says. “We believe this extension is an important first step towards empowering web users to regain control of their privacy online.”

This work was conducted through a collaboration between Carnegie Mellon University, the University of Michigan, Penn State University and Stanford University under the Usable Privacy Policy Project. Other members of the team include graduate students Vinayshekhar Bannihatti Kumar, Roger Iyengar, Namita Nisal, Hana Habib, Peter Story, Siddhant Arora, post-doctoral fellow Dr. Yuanyuan Feng, former undergraduate student Sushain Cherivirala, and faculty collaborators Dr. Margaret Hagan, Prof. Lorrie Faith Cranor, Prof. Shomir Wilson, and Prof. Florian Schaub.