Database Reference
In-Depth Information
Successive graphs derived from the 102 log files of the network data set are
compared using the various graph distance measures to produce a set of
distance scores representing the change experienced in the network from
one day to the next.
7.2.
Experimental Results
Figures 5 and 6 represent the outcomes of connectivity and trac (weighted
graph) spectral distances, respectively, as introduced in Section 3, applied
to the time series of graphs derived from the network data. In spite of the
less intuitive interpretation of these graph distance measures, there exists
reasonable correlation with the peaks of other distance measures and far
less sensitivity to daily variations using this approach (see below).
Figure 7 shows results for edit distance applied to consecutive graphs
of the time series for the topology only measure
d
1
. This measure produces
three significant peaks (on days 25, 65 and 90). The figure also shows sev-
eral secondary peaks that may also indicate events of potential interest.
Also, there is significant minor fluctuation throughout the whole data set
2.5
2
1.5
1
0.5
0
0
20
40
60
80
100
120
days
Fig. 5.
Special distance (connectiviy).
