There must be something in the water, because sharks were big this summer. Discovery Channel's Shark Week opened with its highest ratings ever, and the SyFy Network announced that it will be producing a sequel to its made-for-TV hit "Sharknado."
Both networks enjoyed a serious spike in Twitter activity, which had a lot to do with the programs' popularity.
This is good news for Twitter and Nielsen. The companies are launching a partnership to release social media ratings for the fall 2013 television season called Nielsen Twitter TV Ratings, and they recently released the results of a study (conducted by Nielsen) showing a causal link between tweeting and increased TV viewership.
Both companies stand to gain significantly by convincing networks and advertisers that social ratings will become a key metric in deciding where TV ad dollars are spent—Nielsen in terms of proving its relevance and Twitter as part of the lead-in to its IPO.
Rachael Horwitz, the senior communications manager for Twitter Media, said it's time to capitalize on the connection between TV viewing and Twitter activity. "We think networks should get credit for the conversation they're generating on our platform," she said. "Not only should they get credit, they should monetize it."
The Nielsen study was limited, though. For example, it didn't show whether the sentiment of the social conversation matters with TV. Is it more powerful to have one influencer like Lena Dunham of "Girls" praising "Scandal" (which she did via tweet) or a thousand anonymous tweeters dissing the show's sensational nature?
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Why wouldn't sentiment be a big deal when it comes to Twitter's influence on TV—especially TV, where Americans love to hate.
Twitter and Nielsen say the new watercooler chatter about TV is happening in real-time rather than as recap. That's what advertisers need to know, and that's what the recent study showed.
For Andrew Somosi, the CEO of SocialGuide, a joint venture of Nielsen and McKinsey & Co., sentiment is neither here nor there, at least not yet.
"Sentiment on Twitter is not terribly helpful," he said. Ratings indicate audience share, which is relevant when networks set rates for local advertisers. Whether people have positive things to say about what they're watching doesn't play a big part in that equation.
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Tweets' content does matter, Somosi said. Does someone intend to watch something, do they find a character funny, do they believe in the brand?
But his reasons for dismissing sentiment include the difficulty of expressing full parts of speech with a 140-character limit; tweets often-sarcastic nature, which is hard to pick up; and the fact that people love to hate certain characters.
"Is that good or bad?" Somosi asked.
In addition, "The current sophistication of automated, natural language-based tools for assessing even the basic good, bad, neutral, let alone more complex language, is 'limited' on Twitter," Somosi said. Seventy percent of text tends to be clustered into the "neutral" category, he added.
Nielsen analyzes hashtags, keywords and engagement—whether a tweet includes an @reply or is a retweet, but not sentiment.
But broadcasters are wary of jumping to conclusions about the relevance of social media in judging their content, and specifically, downplaying the importance of sentiment.
Discovery Communications has been making the most of the overlap between social and television for some time. Its programs frequently prompt social media engagement and often include a hashtag on the screen to encourage Twitter conversation.
Discovery even manages imaginary animals' Twitter accounts. #SharkWeek was the top hashtag on Aug. 4, when it launched with the mockumentary "Megalodon: The Monster Shark Lives."
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Guhan Selvaretnam, senior vice president of digital media at Discovery, said that the network hopes that Twitter will drive users back to live-viewing by putting social pressure on the audience to be included in the latest watercooler gossip.
"There is social currency in being part of a discussion," he said, adding that the way people feel about programming is more important than a spike in conversation.
"What matters more is sentiment, because it means long-term engagement," Selvaretnam said. "At the end of the day, what's going to make people watch our show is the quality of our content."
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Topsy collects data on every tweet posted publicly and offers analytics on these tweets for its customers by giving people and products sentiment ratings that indicate how positive or negatively they are mentioned, compared with other things being discussed on Twitter.
For example, after Paula Deen's fall from grace earlier this summer, her Topsy sentiment rating dropped to an all-time low of 13, meaning that out of all the public tweets in the world at that time, only 13 percent were more negative than those mentioning Deen.
And "Megalodon" had a Topsy sentiment rating of 23. Some critics cite Discovery's straying from fact-based documentaries for the public's negative response.
Jamie de Guerre, Topsy's senior vice president of product and marketing, said that putting tweets in context offers a better understanding of the emotions people convey via tweet.
According to Topsy, tweets connected to subjects such as politics have a consistently negative sentiment, whereas when people tweet about companies, the comments are quite positive.
"TV is not that different from politics or brand awareness," de Guerre said. "Tweet volume is hugely important, but whether those tweets are highly positive or highly negative is also an important factor in understanding whether or not the conversation is the best for the show, brand or network. Sentiment can be very valuable for different use cases," de Guerre said.
Some large television advertisers use Topsy's sentiment analysis to measure the response to commercials. Measuring only the quantity of conversation ignores whether or not the conversation is positive for the brand. Adding sentiment to the analysis enables companies to gain rapid feedback that can affect future ad investments. Sentiment is one component of the company's approach, which also includes measuring tweet volume, impressions counts and qualitative analysis of content from fans and influencers.
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Given the importance of social sentiment in other areas, why would TV programming ultimately be any different? And could a major Twitter cycle—a social media equivalent of sweeps week—help companies produce cohesive, relevant advertising strategies, without analyzing the sentiment of the traffic?
"It can reach a point that it is too negative and does not help you to reach your audience in the manner you are intending," de Guerre said, reflecting the concerns of the Discovery Channel about "Megalodon."
Nielsen data from the recent causation study showed that scripted dramas had an 18 percent ratings increase based on tweets—or roughly two out of every ten shows getting some bump based on Twitter. On average, an 8.5% rise in Twitter volume has correlated to a one percent rating increase in the 18- to 34-year-old demographic, according to an earlier Nielsen study.
These data don't suggest a radical change in the TV landscape but rather a statistically significant relationship.
Ultimately, what makes Twitter important in TV—even to those who disagree on the importance of sentiment analysis—is that there is a larger conversation on Twitter about TV programming than there is on Facebook or other social networks.
"Twitter is really becoming the 'second screen' that people now use to join a live conversation around broadcasts," de Guerre said.
For Nielsen and Twitter, the eyeballs are there, and that's what advertisers and broadcasters care about.
As for the effort to measure the influence of tweet emotions about TV content, "Good luck with sentiment for 'Sharknado,' " Somosi said.
—By Matthew Creegan, Special to CNBC.com