Study finds Reddit’s ban of its most toxic subreddits worked (2017)

So they took a major corpus of Reddit data (compiled by PushShift.io) and examined exactly what happened to the hate speech and purveyors thereof, with the two aforementioned subreddits as case studies. They then compared this pre-ban data to the same users post-ban: how much hate speech they produced, where they “migrated” to (i.e. duplicate subreddits, related ones, etc.) and whether “invaded” subreddits experienced spikes in hate speech as a result. What they found was encouraging for this strategy of reducing unwanted activity on a site like Reddit:

Post-ban, hate speech by the same users was reduced by as much as 80-90 percent.

Source: techcrunch.com