By Alyssa Pereira

According to a recent academic paper penned by a former Google fellow, the tech giant may be downgrading search results served by its own engine in order to promote its own properties.

Tim Wu, the former employee who is currently an author and Columbia Law School professor, delivered his paper at Oxford University’s Antitrust Enforcement Symposium with the help of Harvard colleague Michael Luca and the Yelp data science team.

The study utilizes “a random controlled trial in which [the researchers] vary the search results that users are shown, comparing Google’s current policy of favorable treatment of Google content to results in which external content is displayed.”

To test the theory, Wu and researchers compared two sets of results: one using Google’s universal search, and one using a plug-in called Focus On The User (an algorithm that doesn’t pull from a user’s Google+ account).

While the paper acknowledges that the search engine has a “merit-based algorithm” that is capable of identifying the best results for any given search, Wu states that this “organic” serving of search results isn’t what is offered.

The study concluded that Google is “reducing social welfare, leaving consumers with lower quality results and worse matches.”

Wu’s paper echoes what the Federal Trade Commission stated about Google earlier this year, in its statement that, “Our findings suggest that Google is – in some instances, actually making its overall product worse for users in order to provide favorable treatment to Google content.”

However, there is one criticism to the study. Bloomberg reports that Wu was compensated for the article by Yelp, which may have skewed his reasoning.

Wu nevertheless stands by his work.

“I have great respect and admiration for Google as a company, and feel that 90 percent of what they do makes life easier or better,” he told Bloomberg. “In this case, I am convinced that Yelp’s data is showing a deviation from those principles, and I agreed to write the paper to make that point known to the world.”

Read the full study here.