If Twitter drove TV ratings, industry insiders have long pointed out, then The CW’s Vampire Diaries would be a top-rated show.

Yet a new study by Nielsen demonstrates — for the first time — that there is indeed a link between Twitter activity and a show’s popularity.

The ratings measurement company analyzed minute-to-minute trends in Nielsen’s TV ratings and Twitter activity for 221 broadcast primetime programs. Nielsen found the volume of tweets caused “significant changes” among the live ratings of 29 percent of the programs. Less surprisingly, the company found the connection worked both ways — a program’s popularity influenced Twitter activity in 48 percent of the episodes.

“Using time series analysis, we saw a statistically significant causal influence indicating that a spike in TV ratings can increase the volume of Tweets, and, conversely, a spike in Tweets can increase tune-in,” said Paul Donato, chief research officer at Nielsen. “This rigorous, research-based approach provides our clients and the media industry as a whole with a better understanding of the interplay between Twitter and broadcast TV viewing.”

Nielsen says the methodology used for this study was developed by Nobel Prize-winning economist Clive Granger, and is a method widely used in the fields of econometrics, physics and neuroscience.

“These results substantiate what many of our TV partners have been telling us anecdotally for years: namely, that Twitter drives tune-in, especially for live, linear television programming,” said Ali Rowghani, Twitter’s chief operating officer.

The Twitter vs. ratings debate made headlines recently when Syfy’s horror comedy Sharknado received a whopping 5,000 tweets per minute during its premiere night last month. The premiere received modest ratings. But then subsequent airings of the film delivered rising returns — bucking the usual trend of repeat performances.