Social Network Analysis (SNA) measures relationships between people, organizations, or other entities by constructing a network of ties between those entities or “actors”. SNA provides both a visual and mathematical way to analyze those ties [Was94], helping to understand the importance of an actor in the network.

TeCFlow [Glo04] is a tool to automatically analyze social networks based on communication logs. It creates a database from email logs, web links, phone archives, and the like. The entries in the database can be analyzed for different persons, content or other typical categories of social networks. To visualize the results, TeCFlow creates graphs that show the actors as nodes and the relation between them as lines.

A very important aspect that must be mentioned is that TeCFlow can show social networks in a dynamic way. The network is not only shown at a single point in time; rather TeCFlow visualizes the changes of a structure over time. This way TeCFlow creates an interactive movie, where the nodes change their position according to their current position in the network.

In general we studied the Wikinews Network at two different levels of abstraction: On the one hand we analyzed the individual actors and the roles they assume in the network. On the other hand we looked into attributes of the network itself, also in relation to external events.

We formulated the following four hypotheses:

H1: There are a small number of key contributors to Wikinews who form a core network.
H2: Users contribute to various categories. Therefore, no separate interest networks exist.
H3: Active article writers have first been active commentators and later active article editors until they have evolved to actively writing new articles.
H4: External events as well as shifting interests in the community are reflected in the network.

Note that Hypotheses 1 to 3 correspond to the actor-level analysis, while Hypotheses 4 deals with the network-level and external influences.

In the following sections each individual hypothesis is discussed in detail. This involves explaining the goals we planned to achieve with analyzing the hypothesis as well as describing and critically reviewing the approach we took to test it.