File: A picture taken on October 22, 2012 in Rennes, western France shows the screen of a BlackBerry phone featuring a page of the micro-blogging site Twitter. (DAMIEN MEYER/AFP/GETTY IMAGES)

The benefits of the second-screen phenomenon — where TV viewers live-update their Twitter or other social media accounts while watching — are finally becoming apparent. According to a new report from Nielsen, increased Twitter chatter about a television show doesn’t only cheer a program’s most-devoted fans. It also has a small but positive effect on ratings overall.

The research comes from analyzing the minute-to-minute trends the research firm records through its partnership with Twitter. The data don’t offer hard information about how much of a boost social media can give a show, but they do show that tweets “caused statistically significant changes” in live TV ratings among 29 percent of episodes.

The effects are different for different types of shows, the report found. Competitive reality television derived the most benefit from social chatter, with the firm saying that 44 percent of episodes in this genre saw a bump from Twitter talk. Comedies saw a bump 37 percent of the time, while 28 percent of sports programs and 18 percent of dramas saw increases.

The research firm looked at ratings and tweets for 221 broadcast, primetime program episodes.

Of course, the boost goes both ways, with Nielsen also finding that television broadcasts also provide a traffic boost to Twitter — something the social media firm itself has touted by releasing Twitter stats during major events like the Super Bowl.

While Twitter chatter doesn’t give broadcasts a huge punch, showing that a good Twitter campaign can boost ratings is a good selling point for the company as it looks to pitch the value of its service to brands and improve its efforts in the advertising space.

Related stories:

Social media ‘comes of age,’ Nielsen says

Nielsen to measure TV talk on Twitter

Twitter reports Super Bowl’s social statistics

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