twInfluence uses social network analysis techniques to analyze your Twitter followers.
Here's the metrics they are using. I would like to get a sense of what they mean - perhaps scales? How to put this into context? I'm particularly interested in the social capital measure.
Here's the description from the site of the various metrics, but would really like to get a sense of how to use the numbers to improve Twitter presence - and what the scale/range is for some.
First and Second Order Networks: From the perspective of graph theory,
a Twitterer's followers would be considered their first-order network,
and their "followers count" the same as their "degree". "Degree" is a
simple form of centrality measurement that equates to "prestige" or
"popularitiy"; different types of centrality can measure connectivity,
authority, and control in a network. The following diagram demonstrates
the different "neighborhoods" in a network. The Twitterer is the
primary node (shown in red); its first-order neighbors (shown in green)
surround it, and its second-order neighbors (shown in blue) surround
Reach: Reach is the number of followers a Twitterer has (first-order
followers), plus all of their followers (second-order followers). In
the diagram above, the reach would be 27 (there are 28 nodes, including
the Twitterer). This is by necessity a crude maximum estimate, since
there will definitely be duplicates and overlaps that could only be
eliminated by up to thousands of API calls. Reach is a measurement of
potential audience and listeners, a best estimate of the number of
people that a given Twitterer could quickly get a message to.
Velocity: Velocity merely averages the number of first- and
second-order followers attracted per day since the Twitterer first
established their account. The larger the number is, the faster that
Twitterer has accumulated their influence. Of course, this number could
jump significantly with the addition of a few high-profile followers.
Social Capital: OK, I'm abusing the academic term "social capital" a
little to indicate the average first-order network of a Twitterer's
followers. A high value indicates that most of that Twitterer's
followers have a lot of followers themselves.
Centralization: This is a measure of how much a Twitterer's influence
(reach) is invested in a small number of followers. Centralization
scores range from 0% (completely decentralized) to a theoretical 100%
(completely dependent on one Twitterer). In social network analysis, a
high centralization indicates dependency of the network on just a few
nodes to maintain the connectivity of the entire network. Twitterers
with low centrality networks would not have their reach greatly reduced
if a few high-profile people stopped following them.
Efficiency: The more people you follow, the more time you have to spend
reading and filtering tweets. I've heard it argued that nobody can
effectively and consistently follow more than a couple hundred
Twitterers and actually keep up with the tweetstream. Efficiency is
simply my measure of how many people a Twitterer had to follow in order
to build up their reach, as a percentage. Highly "efficient" people
like Will Wheaton follow only a few dozen people even though they
themselves have thousands of followers! Ideally, this would measure a
Twitterer's Friends' collective "number of updates" relative to reach,
but we have to make an excessive number of API calls as it is.