The experiment showed that messages don’t need highly
connected people to get to a specific destination. But what if we’re
interested simply in making something spread as far as possible?
Could people who are more connected in the network – like
celebrities – help ensure it takes off? A few years after the e-mail
analysis, Watts and his colleagues looked at how web links propagate
on Twitter. The results suggested that content was more likely to
spread widely if it was posted by a person with lots of followers or a
history of making things take off. Yet it was no guarantee: most of the
time these people weren’t successful at creating large outbreaks.[6]
Which brings us to the more basic version of the influencer
hypothesis. This is simply the idea that some people can be more
influential than others. There is plenty of evidence to support this. For
example, in 2012 Sinan Aral and Dylan Walker studied how a
person’s friends influenced their choice of apps on Facebook. They
found that within friendship pairings, women influenced men at a 45
per cent higher rate than they influenced other women, and over-30s
were 50 per cent more influential than under-18s. They also showed
that women were less susceptible to influence than men and married
people were less susceptible than singles.[7]
If we want an idea to spread, we ideally need people to be both
highly susceptible and highly influential. But Aral and Walker found
that such people were very rare. ‘Highly influential individuals tend
not to be susceptible, highly susceptible individuals tend not to be
influential, and almost no one is both highly influential and highly
susceptible to influence,’ they noted. So what effect could targeting
influential people have? In a follow-up study, Aral’s team simulated
what would happen if the best possible people were chosen to spark
a social outbreak. Compared with choosing randomly, the pair found
that picking targets effectively could potentially help things spread up
to twice as far. It’s an improvement, but it’s a long way from having a
few little-known influencers who can spark a huge outbreak all by
themselves.[8]
Why is it so hard to get ideas to spread from person to person?
One reason is that issue of people rarely being both susceptible and
influential. If someone spreads an idea to lots of susceptible people,