| Sun | Mon | Tue | Wed | Thu | Fri | Sat |
|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | |||
| 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| 26 | 27 | 28 |
« The genetic basis (?) of political orientations | Main | Spring schedule for Cambridge Colloquium on Complexity and Social Networks »
14 February 2006
I’m beginning a collaboration with British Telecom in an effort to analyze their massive call network dataset. This is a dynamic, directed network that contains ~250 million nodes (ie: distinct phone numbers) and ~2000-5000 edges (ie: calls) generated each second. The phone numbers are of course one-way hashed such that it is impossible to link a node’s identifier to an actual phone number. However we do have information about the country and region to which the node belongs (ie: country code / area code). While it is not inclusive of every call to and from the UK, it is estimated that the dataset includes approximately 80% of landline calls and 30% of mobile calls.
So my question to the complex systems / social network community is this: what are some questions we should attempt to ask of this dataset? Possible examples include calculating the strength of a particular region’s relationships with other regions and countries, analyzing the dynamics involved in “call cascades�, inferring the average size of an individual’s hierarchical social groups (from close friend to possible acquaintance), etc...

While many metrics may be impossible to calculate for a network of this magnitude, simple sampling can yield interesting results. For example, the plot above represents the duration of outgoing calls from 100,000 randomly sampled nodes during 6 month intervals over the course of October 1995 to March 1998. It is clear that there are an increasing number of very long calls (over 10^4.2 seconds ~ 4.5 hours) which could be a good indicator of the uptake of dial-up internet in the UK during this timeframe.
Posted by Nathan Eagle at February 14, 2006 9:21 AM