Information Technology Reference
In-Depth Information
For the first problem, we can expect that a person who had accepted the
commitment and responsibility as a evaluator would withstand the rumor. We
can consider a way to control the phenomenon of information cascading to deal
the second problem.
5.8.1 Merits of the Phenomenon of Information Cascading
There exists some positive side of the phenomenon of information cascading. This
phenomenon is the origin of the power of information distribution. With this
phenomenon, a user of social web services can get fresh and valuable information
and can distribute their own ideas to the people who need them.
5.8.2 Anxiety Reduces the Thresholds of Weakly Tied People
A person without the means to confirm an object directly tends to follow another
person's evaluation easily. When people are anxious, it is hard to maintain
reasonable thresholds. For example, in the midst of a major disaster people feel
anxious about the contamination of food, and erroneous information can be
spread.
5.8.3 How to Control the Phenomenon of Information Cascading
A small amount of information cascading always occurs everywhere in small
communities over a huge social web service. In a small community it is natural
that some important information will spread all over the community. Sometimes
small cascading triggers large scale cascading in this way. The precise conditions
which cause such large cascading is not known. Because small cascading is useful,
we try to control the size of cascading.
5.8.3.1 Betweeness Centrality of a Network
“Betweeness Centrality” is a popular index to represent the centrality of the
network structure (Barthelemy
2004
). A vertex which has a high value of
betweeness centrality is a mediator of multiple communities. In the example of
Fig.
5.8
,
v
1
seems to be central vertex because vertex
v
0
has only three arcs and
vertex v1 has six arcs. However, give all the pairs of the vertex in the network and
