Google still personalizes search results even when users are logged out or in private browsing mode, according to a study from DuckDuckGo.
It’s commonly known that Google personalizes search results while users are logged in based on their account information and browsing history.
However, this new study concludes that it’s not possible to use Google in any capacity and avoid personalized search results.
Same Keyword, Same Time, Different Results
The study involves users entering identical search terms at the same time.
Participants in the study were all located in the US because different countries have different search indexes
Most participants saw results unique to them regardless of being logged in or not.
A total of 76 people searching for the same keyword at the same time returned 62 different sets of search results.
Google returned some links on the first page that it did not show to others, and results in the news and video boxes varied significantly.
In addition, DuckDuckGo says the differences in search results could not be explained by changes in location, time, or by Google testing algorithm changes.
Sources in the news carousel were different even when users searched at the exact same time.
When testing for differences in unique domains being displayed, the study found that 87 people saw 19 domains ordered 31 ways.
Some results returned domains that no other participants saw.
Google’s “Filter Bubble” Problem
Contrary to what some people believe, browsing in incognito mode does not provide users with anonymity.
“Unfortunately, this is a common misconception as websites use IP addresses and browser fingerprinting to identify people that are logged out or in private browsing mode.”
DuckDuckGo argues that this creates a “filter bubble” because Google is filtering peoples’ search results, keeping them in a bubble based on what its algorithms think a user is likely to click on.
For more information, see the full study here.
Subscribe to SEJ
Get our daily newsletter from SEJ's Founder Loren Baker about the latest news in the industry!