» Google delivers ads based on your personal profile

Google delivers ads based on your personal profile

Google starts delivering ads based on a profile of your personal interests. Should you be worried about your privacy?

People who log in to their Google account and make use of services like Google Bookmarks or Google Web History Google will give you personalized search results.

Google automatically makes a profile of your interests based on your surfing habits and then try to adjust the search results to you liking.

Today Google will start experimenting with personalized ad delivery or what they call “Interest-based advertising”.

The Google Blog says:

“These ads will associate categories of interest — say sports, gardening, cars, pets — with your browser, based on the types of sites you visit and the pages you view.”

Google has put up a separate page that lets you opt out of this program altogether or adjust your personal profile by adding interests.

It is based on cookies, not account data

There is one big difference between personalized search and interest-based advertising:

Interest-based advertising is not based on information fetched from you Google account.The ad system does not analyze your Google email or web history to make the personal profile.

Instead it makes use of a so-called cookie, a small text file that is stored on your computer. This cookie gives the user of your computer — i.e. you — an identification number, a random string of letters and numbers that Google makes use of when designing your profile.

DoubleClick technology

Google acquired this technology when buying the ad network DoubleClick.

Google says:

For our AdSense program, we serve ads based on the content of the site you view. For example, if you visit a gardening site, ads on that site may be related to gardening. In addition, we may serve ads based on your interests. As you browse websites that have partnered with us or Google sites using the DoubleClick cookie, such as YouTube, Google may place the DoubleClick cookie in your browser to understand the types of pages visited or content that you viewed. Based on this information, Google associates your browser with relevant interest categories and uses these categories to show interest-based ads.

Since the cookie does not contain your name or any other information that tells the ad system who you are, the system should in principle be anonymous.

Of course, if you do have a Google or YouTube account with personalized information, it should not be difficult for Google to associate the cookie with you gmail account, but the company asks us to trust them on this one.

Advertisers deliver profiling data

What’s really interesting is that Google also will allow advertising partners to add additional data:

Some of the sites and services (such as social networking sites) that use our AdSense program also may use information that doesn’t identify you personally, such as demographic data, to provide relevant advertising. Google will not associate sensitive interest categories with your browser (such as those based on race, religion, sexual orientation, health, or sensitive financial categories), and will not use such categories when showing you interest-based ads.

Indeed, according to Search Engine Land, Google may even add information on your online shopping. So, if you abort a transaction at — let’s say — an online stereo store, that store may serve you an ad for that product on another site that is part of the program in order to entice you back to their store.

What about your privacy?

What seems clear to us is that any site that carries a Google ad of this time may add information to your profile. In other words, Google pairs the ad with the cookie and stores your activity in their database.

Google may also add information on what you are doing at these sites, for instance what kind of videos you watch over at YouTube.

Should you be worried about your privacy?

Well, as we have said before, this system is based on trust. If Google loses that trust, the whole business model falls apart, and Google does not want that. In other words: the chances that Google will start using these data for other more unsavoury purposes are slim.

The problem is that others may try to get access to the data.

There is no such thing as a perfect system. One day someone at Google may make a mistake or a cracker slips through. Then there are public authorities. Who knows to what kind of Google data US intelligence may access post-9/11?

In other words: If you cannot afford to give aways clues about your surfing habits, do kill that cookie! And if you do, also make sure to install Google’s Cookie Opt-out pug-in to stop the system from adding a new cookie at a later time.

We expect this new system to generate a new debate on web privacy. Google will most likely be asked why they have instituted an opt-out policy instead of an opt-in policy, as they have for personalized search.

The family as one user

Google uses your computer and the cookie as a proxy for one individual user. This tactic poses two problems:

Firstly, many computers may be used by many. Mum is looking for guns and ammo, dad for the latest fashion tips and the son is searching for… well, let us not even go there. In other words: Google’s profile may be an amalgamation of different interests.

If you believe that having Google target ads for you is a practical and good thing, you should probably set up separate user accounts for all these people or make them use different browsers: Opera for dad, Firefox for mum and Chrome for the kids.

Secondly, Google will get insufficient data for their profiling if you use several computers, and many of us do. We use a PC at work, a Mac at home and an iPhone on the run. Google has no way of coupling these cookies.

Here’s a Google video presenting the system: