Abstract Processes. It is possible to apply an ab-
stract process of network generation. The proposed
methods are often very simple but provide often only
good results on few properties at a time. These prop-
erties have been observed enough times on different
social networks to be considered as fundamental.
• Random network (RN) (Erdos and Renyi, 1959).
The only parameter is the probability for a node
to create an edge with another node. This process
assures a direct control on the density of the re-
sulting network.
• The Preferential Attachment (PA) algorithm
(Barabasi and Albert-L
´
aszl
´
o, 1999) provides a
network with the scale free property, i.e. a power
law distribution of degrees. The construction in-
volves an iterative process in which an incoming
node will be linked with a stronger probability to
an high degree network node.
• Small World (SW) (Watts and Strogatz, 1998)
generates networks with a correct clustering and
a small average path length, known as the small
world effect. The most cited model corresponds
to the construction from a regular lattice, rewiring
at random edges with a certain probability to an-
other random node.
Although these processes are very simple, they are
the most used, at least by the JASSS community (Am-
blard et al., 2015), mainly because their use is very
simple. They also allow modelers to test their sim-
ulation results based on a single but easy to control
network property.
Statistical or Stochastic Models. In those ap-
proaches, the existence of an edge between two given
nodes of the network is considered as a probability,
and the model will determine them. Those methods
have often a network as target, like it is the case for
the following items.
• p*/ERGM Exponential Random Generative Mod-
els (Robins, 2011) is a family of statistical mod-
els in which modelers has to choose a set of net-
work patterns (called terms or factors) that may
describe to a certain level of precision a given net-
work. A model fitting process allows to determine
the relative importance (factor value) of terms in
the observed network structure. Each factor value
expresses how likely the feature is to be found,
compared to a random network of the same size.
ERGM allows to generate networks with respect
to any valid combination of terms (e.g. degree
distribution, substructures, edges and nodes vari-
ables, etc.).
• For Kronecker Graphs (Leskovec et al., 2010),
the idea is to start from a 2x2 or 3x3 stochastic ad-
jacency matrix that will be enlarged by a recursive
method. Correct starting parameters will then be
searched by comparison with the target network.
This model is good at generating graphs with an
appropriate degree distribution and network diam-
eter. Also, properties on the adjacency matrix as-
sociated with the graph have good eigenvalues and
vectors.
• Menezes and Roth method (MR-method)
(Menezes and Roth, 2014) is searching for a good
formula defining p(i,j), the probability of having
a link between two nodes of a target network.
Generating a synthetic network with p(i,j) and
using a distance to a target network as the fitness,
the model uses a genetic algorithm in order to
make evolve p(i,i), trying to find the closest
synthetic network possible.
2.3 Contribution
Concerning the agent-based generation, while behav-
iors incorporated in agents are realistic, it is difficult
to get a network with good properties. Real phenom-
ena are more or less stylized and the results can be, in
the best case, correct in a qualitative way.
Concerning the abstract processes – SW, PA, RN
–, one can argue that resulting networks can be used
for qualitative results. In fact, far more network topol-
ogy properties influence the speed of propagation, as
Cointet and Roth (Cointet and Roth, 2007) pointed
out. They advise to use any real world network, even
from others field, to get better results. Classic stylized
networks give incoherent results mainly because these
networks do not take into account properties that do
matter for processes like propagation, e.g. the dia-
mond clustering that will slow down speed (a triangle
closure extended to four nodes). For the qualitative
approaches, network generation processes can be too
abstract or too hard to configure. Parameters cannot
be interpreted easily, and in the case of ERGM there
are some real difficulties using it without the required
knowledge.
Besides, our method is fundamentally different in
the approach while we hope being able to give close
quality of results, with a configuration-free method
and in a dynamic way.
3 MODEL DESCRIPTION
Our model need to be usable in several cases of appli-
cation, that is why available behaviors for the agents
Dynamic Agent-based Network Generation
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