For some time, most marketers have agreed that if you want to grow a social media website, or sell stuff through one, a good strategy is to target your offering to "Influentials." If you define Influentials as highly connected people who try stuff out and like to advise others about it all (Keller & Berry, 2003), the thinking has been that these folks are better able to spread an idea than less-connected people.
But targeting Influentials costs money, so it had better work.
Last year, network mathematician and sociologist Duncan Watts together with Peter Dodds (2007) published the results of their computer models of complex networks that questioned this view. Essentially, under a variety of assumptions they found that highly connected people were no more likely than average-connected people to start "cascades," that is, the widespread viral propagation of an idea that ends up being seen by most everyone (like the Facebook explosion, or hush-puppy shoes). Using a forest-fire analogy, Watt & Dodds wrote "no one would claim that the size of a forest fire can be in any way attributed to the exceptional properties of the spark that ignited it." So too, the size of a fad, they found, bears little relation to the popularity of the person who started it.
Watts & Dodds (2007) didn't argue that Influentials don't exist; they concede that they're highly connected and that they try to influence others. But they believe that what's more important is that the ideas get to "easily influenced individuals influencing other easy-to-influence people." Using their forest-fire analogy, they argue "wind, temperature, low humidity, and combustible fuel" are more important to a raging fire/fad than the spark.
Put another way, the subtitle for Keller & Berry's (2003) book is "One American in Ten Tells the Other Nine How to Vote, Where to Eat, and What to Buy." Watts is just saying that doesn't mean they listen. Or pass it on. And that's what matters. It's not about Influentials, it's about the Influenceable.
The debate has only begun, and it will likely take years of semantics, modeling, and empiricism to come to a new refined consensus. BUT in the mean time, you can take advantage of this issue to make sure you're not ignoring any strategy you could be taking with your network.
You should be paying attention to all of the below properties of your network to grow or sell stuff, not just a few of them.
1. increase number of people we all pay a lot of attention to this...
2. increase appeal of the idea ...and this
3. increase number of connections between people. We have Keller & Berry to thank for bringing this to our attention. But it's not all...
4. strengthen the connections between people Watts reminds us of this, which is the intimacy or authority of a connection between people determining how often a recommendation from one to the other is heeded
5. lower the threshold for people to forward and Watts reminds us of this, which is the likelihood that a person will consume and, more importantly, recommend an idea on.
6. increase the number of unique people who forward something to you this is how many different people need to recommend something to you before you adopt. I'll visit a website based on one recommendation. But it takes two to get me to try a restaurant, and four to get me to go to a movie.
The slide deck below shows some ways that designers improve each of the above properties of social networks. Here's a quick verbal summary of two of them:
4. strengthen the connections between people ...oddly enough, you do this by encouraging people to reject friend requests from total strangers. If the digital friendships have no real-world counterpart, they're as meaningless as drawing a line between two random names in the phonebook, and those connections sure as heck aren't going to influence each other to act.
5. lower the threshold for people to forward ...obviously, by making it easier for forward for starters....the goal used to be "1-click forwarding" but then Facebook set a new standard "0-click forwarding"...meaning that they unified the click needed for people to consume content and the click needed for them to forward it into the same click...when I add the YouJustGetMe app the link is automatically forwarded to all my friends on the feed.
And the real lesson here is: All of the above network properties are important. Do some surveys or usability testing (maybe with us!) to learn how to turn up the dial on all of them.

