On social media, the Yankees have a bigger presence than the Mets, but that's simply because they have a larger fan base, both locally and nationally. In terms of sentiment, however, Mets fans are happier. According to data from social media analytics firm Brandwatch, 72 percent of Mets tweets are positive (among the ones that can be categorized by sentiment). That's higher than the 61 percent number the Yankees tweets show.
Even though the Yankees fan base is larger by a factor of 4, Brandwatch's data shows the Mets fans are more engaged per person—about twice the average Yankees fan. "With a larger Twitter follower base," said Kellan Terry, a Brandwatch data analyst, "the Yankees should be leading these statistics by a larger margin."
The Yankees have a different perspective on the whole issue, focusing on their position rather than their trend. "We lead the American League in attendance with over 40,000 fans a game," said Jason Zillo, a Yankees spokesman. "We are averaging close to 3,000 more fans a game than the next closest team," he said—again only focused on the AL, rather than all the majors. Zillo pointed out that the team will draw over 3 million fans for the 17th consecutive season, and its YES network will be the most watched in the country.
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As far as the new ticket deals being offered, he said, "good organizations should always look at ways to evolve," and that the team is "constantly evaluating all of our practices ... to provide the best fan experiences possible."
Finally, as far as the Mets go, Zillo didn't look at them as competition directly, saying "it's good for baseball" and the city can support two teams. Rather, he focused on the broader NYC environment. "New York is the most competitive entertainment market in the world. The options are vast and diverse. Broadway, concerts, museums, movies and the like are our competition as much as anything."
Thursday night begins a four-game home stand against the Chicago White Sox. Let's see how many people show up.
—Additional reporting from CNBC's Jodi Gralnick and Jessica Golden.