Duncan Watt's research (download
the full PDF here) has been getting a lot of attention around the blogosphere lately (
Noah Brier,
Gavin Heaton, and
Valeria Maltoni) and I think that it warrants a big caveat.
The Theory of Influentials, as generally described in
Malcolm Gladwell's The Tipping Point, and
The Influentials by Jon Berry and Ed Keller, asserts that a small fraction of the total population of a given community have a disproportionate affect on the community's likelihood to adopt a new trend. As Watts acknowledges, this influence is due to an individual's reputation, knowledge on the given topic, or simply their many connections to other people in the community.
As described in
this Fast Company article, Watts' findings seem to fly in the face of this assertion.
[Watts] programmed a group of 10,000 people, all governed by a few simple interpersonal rules. Each was able to communicate with anyone nearby. With every contact, each had a small probability of "infecting" another. And each person also paid attention to what was happening around him: If lots of other people were adopting a trend, he would be more likely to join, and vice versa. The "people" in the virtual society had varying amounts of sociability – some were more connected than others. Watts designated the top 10% most-connected as Influentials; they could affect four times as many people as the average Joe.
Watts discovered that so-called Influentials are no more likely than any random individual to start a viral trend.
In his paper, Watts writes that the variable in his model that refers to an individual's influence should be thought of as referring "not to how many other [people an individual] knows, but how many other [people an individual] influences with respect to the particular issue at hand." So it's not just how connected a person is, but a complex combination "of [an individual's] personal characteristics, subject matter expertise, authority with respect to the issue, and even the characteristics of the other individuals in [the individual's] community." However, an individual's influence is "mathematically equivalent to the notion of 'acquaintance volume,'" or how many people an individual knows.
So Watts is boiling all of that complexity that goes along with the theory of influentials down to a single number that has the same mathematical weight in his model as simply knowing a lot of people. Or, in other words, in Watts' research, an influential has no more sway over his or her peers than anyone else in the community; they simply affect more people.
So, if you believe that a small portion of a community is disproportionately persuasive in getting the rest of the community to adopt a new trend, regardless of that select group's reach, then Watts' research doesn't tell you anything.
I assert that each of us, as individuals, is connected to a complex social network – much more complex than Watts' model reflects. Some of our networks are larger than others, but our ability to be affected by other individuals in our community varies greatly from relationship to relationship. The variable ability of any other individual to influence our personal choices depends on our personal perception of that individual, how well do we know them? do we trust them? do we respect their opinion? And for each of us, there are a few individuals who carry a disproportionate sway over our inclination to change our position on a given issue. I'd like to see another study in which another variable – independent of Watts' influence variable – that reflects this aspect of social dynamics is added to the model.
In the mean time, we should all take Watts' study with a big grain of salt, before we start tossing the concept of influentials into the trash bin.
If you think I've misunderstood Watts' research, or if there's further research that I've missed, please say so in the
comments.
UPDATE:
Ilya at Adverblog makes a good point: "My own beef with the theory of influentials is its implicit assertion, in my understanding of The Tipping Point, that if you have influence over a certain social network, this influence will have the same weight over the entire range of topics."
Mike Arauz is a strategist at 
