The Harvard Business Review’s list of breakthrough ideas for 2007 includes a contribution from Duncan J. Watts of Columbia University. It details research he and colleague Peter Dodds carried out into the impact that influentials – “a tiny minority of special individuals…who are unusually informed, persuasive or well connected” – have in driving the actions of larger communities.

The pair used computer simulations of populations, manipulating variables relating to people’s ability to influence others and their tendency to be influenced. In contrast to beliefs held by many marketers, the best recipe for spreading influence wasn’t through a small group of influential people. The key factors were the availability and connectedness of many easily influenced people, “just as the size of a forest fire often has little to do with the spark that started it and lots to do with the state of the forest”.

It’s difficult to draw broad conclusions on influencers, as every market where these dynamics are at play has different characteristics. While the study confronts the stereotype of popular kids influencing the clothing brand choices of their peers, it ignores market-specific factors such as the influence that a respected product review blogger has over the purchasing decisions of regular readers.

The author recognises this, asserting that the real value of the study is that it clarifies the point that while “it is almost impossible to generalise from one situation to another…such generalisations are difficult not because of insufficient data but because any focus on individual attributes alone overlooks the importance of network effects”.

All of which makes me glad to be in PR. Understanding influencers means understanding relationships – an attribute that has always been at the heart of the discipline.