WASHINGTON, DC — Saying computer users should be notified when their online habits are tracked by advertisers and publishers, a coalition of privacy advocates has called for the creation of a “Do Not Track” list similar to the “Do Not Call” telephone registry that prohibits marketers from contacting unwilling phone owners.Backed by the Consumer Federation of America, the World Privacy Forum, the Center for Democracy and Technology and other organizations, the proposal comes in the wake of predictions that online advertising revenue will more than double to $44 billion between 2006 and 2011.

In addition, the proposal urges the Federal Trade Commission — with which it currently rests — to require websites to make their privacy policies easier to find and understand, and to provide surfers with simpler ways to opt out of data-collection routines.

On one side of the issue, advertisers and publishers say behavioral tracking increases the relevance of advertising messages delivered to consumers.

On the other, privacy advocates say the vast amounts of data collected and maintained by companies like DoubleClick Inc. represent a significant privacy threat. Not only could the practice conceivably lead to economic profiling that would be unfair to lower-income surfers, but online data warehouses are vulnerable to security breaches and governmental intrusion.

In response, Time Warner Inc. unit AOL recently began a consumer-awareness campaign to educate its customers about targeted advertising. As part of the campaign, AOL officials promised to provide consumers the opportunity to opt out of tracking easily, according to an Associated Press report. The company’s new ad-tracking technology, developed by Tacoda (which AOL acquired earlier this year), employs a new kind of browser cookie that automatically resets itself to “opt-out” even after a user clears all the cookies from his or her browser’s cache. An AOL official suggested the technology could be used as a de facto standard for a national “Do Not Track” list.