Banning bigoted and hateful threads on Reddit successfully reduced the amount of hate speech on the platform, according to a new study.

Researchers at the Georgia Institute of technology analyzed over 100 million Reddit posts from before and after administrators banned the fat-shaming r/fatpeoplehate and white supremacist r/CoonTown in 2015.

Specifically, the study looked at how much hate speech users wrote pre- and post-ban, if they went to similar subreddits or created new ones and whether or not they “invaded” other threads. Researchers also created a control group by which to measure their results.

“For the banned community users that remained active, the ban drastically reduced the amount of hate speech they used across Reddit by a large and significant amount,” researchers wrote in the study.

The ban reduced users’ hate speech between 80 and 90 percent and users in the banned threads left the platform at significantly higher rates. And while many users moved to similar threads, their hate speech did not increase.

“The observed changes in hate speech usage were verified to be caused by the ban and not random chance, via permutation tests,” researchers wrote. “In simpler terms, the migrants did not bring hate speech with them to their new communities. Nor did the longtime residents pick it up from them.”

The study notes that the bans did send some users to places like Voat and Snapzu, which are similar to Reddit but are often referred to as “darker” corners of the web for their lack of censorship and content monitoring.

Reddit has been met with split opinion over banning threads that are frequented by white supremacists, neo-Nazis, racists and bigots who use the forums to harass women and minorities. Though many applaud the effort, many also claim that it violates free speech and that freedom of speech means tolerating hate speech.

But, since Reddit’s goal was to eliminate the amount of hate speech on the platform, the study concludes their efforts are an encouraging success.