According to a new Nielsen study, an increase in tweets directly causes more tune-ins for TV shows. Relying in live TV ratings and tweets for 221 primetime broadcast episodes, the study found a correlation between tweet and tune-in surges. At the same time, a ratings boost also means more tweets almost half the time, while an increase in tweets boosts ratings 29% of the time. Nielsen saw a statistically significant casual influence, which means that TV ratings can increase the volume of tweets, and an increase in tweets can cause a spike in tune-ins. It remains unclear whether this is a universal standard, or just across programs with already elevated social engagement, but proof of two-way causation between tweeting and tuning in could be extremely helpful for pitching Twitter’s new TV ad targeting product, among other campaigns.