Tracking the impact of a story online - a partial solution

Many 'influence trackers' online implicitly assume that all mentions of an issue online are equally meaningful. This is clearly rubbish - not least because different websites have very different sized audiences online.

There's no easy way to crack this - because there isn't a public directory of the number of users that most websites have.

However on Twitter at least you can see how many followers a user has - which allows you to have a decent stab at estimating reach for stories which are discussed on Twitter.

The helpful Backtype.com website aggregates followers for each mention of a specific URL and gives you a reach figure. So for today's BBC story on a camera that can take photos round corners, it gives a Twitter reach of 281,000.