This document introduces methods for representing and analyzing the accessibility and path structure of temporal networks. It begins by contrasting static and temporal network representations, with temporal networks accounting for the chronological sequence of edges. Accessibility matrices and graphs are described as ways to measure the number of paths between nodes. Examples are provided analyzing accessibility in static and temporal networks using empirical data on livestock trade and human contact networks. The analysis finds temporal representations better capture causal paths. A software tool for calculating temporal network accessibility is also introduced.
6. chronologic sequence of edges
fundamental difference to static: causal paths
Mon
Tue
Wed
causalpath
causal
paths
7. accessibility matrices &
accessibility graphs
adjacency matrix A:
number of paths of length 1
square of adjacency matrix A2:
number of paths of length 2
Example (static):
34. causal fidelity
results II
comparison:
static vs. temporal accessibility-graph
number of paths:
static representation: 1.4 billion
temporal representation: 1.0 billion
28 % of all paths in the
aggregated network do actually
not exist!
54. example
usage
# File: Unfold_Accessibility.py
from MatrixList import AdjMatrixSequence, Tools
At = AdjMatrixSequence("Edges.txt",directed=True)
c = At.unfold_accessibility()
h = Tools.cdf2histogram(c)
55. example
usage
# File: Unfold_Accessibility.py
from MatrixList import AdjMatrixSequence, Tools
At = AdjMatrixSequence("Edges.txt",directed=True)
c = At.unfold_accessibility()
h = Tools.cdf2histogram(c)
Tools.dict2file(c,"Path-density.txt")
56. example
usage
# File: Unfold_Accessibility.py
from MatrixList import AdjMatrixSequence, Tools
At = AdjMatrixSequence("Edges.txt",directed=True)
c = At.unfold_accessibility()
h = Tools.cdf2histogram(c)
Tools.dict2file(c,"Path-density.txt")
Tools.dict2file(h,"Histogram.txt")
62. paper.
Unfolding Accessibility provides a
Macroscopic Approach to
Temporal Networks
Hartmut H K Lentz, Thomas Selhorst and Igor M Sokolov
Phys. Rev. Lett, 2013
63. “ ”
No man ever steps into the same river twice.
Except Chuck Norris!
- Heraclitus