Turns out people love their stars on Twitter almost as much as they love their stars on TV, according to a new study by companies with an intense interest in the results.

Just as importantly for the TV business, fans also like the brands that back the shows they tweet about, according to the study by Twitter, Fox and industry-backed group the Advertiser Research Foundation.

More generally, the TV-related tweets most likely to motivate a viewer to watch will come from an actor on the show or other cast member (40%). That’s well ahead even of tweets from the user’s friends and family (26%), the social-media source that conventional wisdom suggests would be most influential. Perhaps less surprising is the finding that tweets from a show’s official Twitter account motivate barely more than one in six users (just 18%). 

Twitter users and TV tweets graphicMore than 90% of those who see show-related tweets have at some point taken immediate action to watch, search for, or share content, the study says. The majority of those exposed to TV-related tweets immediately take action around the show, are highly likely to watch a show they’ve never watched before, or to resume watching a show that they’d previously stopped watching.

That finding would significantly bump up the importance of Twitter as a way to market and build audience for TV shows, presuming that the program’s stars are engaged in that effort. A few shows have been particularly effective in this regard, such as ABC’s Scandal, whose cast members routinely live tweet and respond to fans through Twitter as each week’s show plays.

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That said, Nick Reed, a strategist at social-media analysts RelishMIX, said focusing too much on one of the big platforms such as Twitter would be a mistake, given that TV is a visual medium that should leverage its strengths on YouTube with outtakes and other video material while building a substantial Facebook presence as well.

“Not leveraging the strengths of Facebook, YouTube and Twitter and just focusing on one of them is like cooking without salt,” said Reed. “Not very smart.”

The Advertising Research Foundation study also contains some encouraging news for advertisers, because the brands associated with a Twitter fan’s favorite show tend to get spillover goodwill and increased attention to their commercials. Twitter-engaged viewers are far more receptive to ads running in their favorite, most-tweeted shows. The study looked at, for instance, fans of Fox’s most tweeted show, American Idol, and found that those who talk about it on Twitter are 16% more inclined to like and buy brands that advertise on the show, even when compared with other Twitter users, never mind the broader Idol audience.

idol feb 20“We know that Twitter is a complement to TV for audiences, and we’ve seen that running Twitter media alongside TV media drives greater TV ad effectiveness,” Twitter’s global director of advertiser research Jeffrey Graham said. “This new research helps us better understand the role earned media plays in driving cross-channel effectiveness.”

That means the shares and mentions a show, or its advertisers, get on Twitter can lead to more sales at the store. You can see why Twitter and Fox like their study’s results.

The study will be released officially today at the foundation’s Re:Think 2014 conference, and is based on responses from nearly 13,000 people recruited on Twitter’s website and mobile app over a two-week period. The study was conducted by db5 on behalf of Fox and Twitter.