After a recent discussion with a non-marketer who studies citation networks, I’ve been asking musing on influence in social networks. What is it, exactly? Does it depend on the network? Is it as difficult to define as charisma? Or is it an (albeit inexact) something that an analyst can feasibly zero in on?

The question may be too big. It may simply depend on the network. But its worth asking, because it would be fantastic information for any company performing social media analysis to know.

Blog and other online social networks are not unlike academics’ citation networks. Research on these can inform this investigation. Citations, like comments on a blog, can not be removed or added after the fact to a post, meaning that despite continual evolution at the “leading edge” of a network, the structure is mostly static.

In traditional network theory, there are cut-and-dry definitions for metrics that begin to pinpoint the influence that SEMs talk about. What’s interesting is that research of specific networks often determines key influencers to be the same, regardless of metric used. In citation networks, it is commonly the fact that these key influencers are those that have been around a relatively long time.

I have a feeling (which I would certainly like to try and back up with data) that a similar situation probably exists in many blogging communities.

If you’re analyzing a blog community, and can find a correlation between time a participant joined and their influence, a question immediately arises as to why this is the case. Do people tend to link to or reference these key influencers because they are experts on a given topic, because they are tuned in to the driving forces/topics in a given field, or because they have been around the longest, and everyone else cites them?

It suddenly becomes a question of measuring influence in multiple directions at once – the key player on those reading, and the opinions of other participants on each other. Not one I can answer at the moment, but one that’s unlikely to go away.