It should be easy to tell whether or not something’s working on social media, right? I mean, if you’ve got a lot of likes and favorites, that’s great. If you don’t, that’s less great. Isn’t that how it’s supposed to work?
Well, not quite — at least according to DigitasLBi. The marketing agency worked with Wharton professor Jonah Berger to develop a new way to evaluate social media effectiveness, which it’s calling the Contagious Index (appropriate, since Berger wrote the book “Contagious: Why Things Catch On“).
“I think the goal is to shift the conversation,” Berger said. “Many brands are dissatisfied with social media, and part of that is, the wrong thing is being measured.”
Apparently there’s a lot of fancy math that goes into boiling down a brand’s social media strategy into a single number, but Berger and Jill Sherman, DigitasLBi’s senior vice president of social strategy, identified a few key things about their methodology.
For one thing, the index is “normalized by impressions,” meaning that you don’t just get a high score because you have a lot of fans. After all, if you’ve got millions of followers, you’re pretty much guaranteed to get a respectable amount of engagement for every post, but that doesn’t mean you’re doing a great job. Someone who’s got a smaller following might actually be doing a better job of connecting with their customers and fans, even if they get less absolute engagement.
The score is also weighted based on the “activeness” of the engagement. In other words, it’s easy for me to click like or favorite on something, but it means a lot more if I’m willing to leave a comment or to re-share the post with my own followers.

Sherman also said the Contagious Index isn’t really for scoring individual pieces of content, but rather “aggregate actions — can a brand consistently maintain contagiousness or virality for their reach over time?”
In addition to assigning brands a score out of 100, DigitasLBi also makes an effort to identify the kinds of strategies are working.

DigitasLBi says the Contagious Index is available to all of its clients. Sherman added that it’s probably not suited for every business on social media.
“This really is about content,” she said. “It really is for brands trying to play int he content space in a meaningful way in social.”

Update: Added the top 10 lists for Facebook and Twitter.
