Summary: Spreading processes on networks
In some cases is not enough to specify the nodes (components)
and edges (interactions).
What are the dynamical aspects of the interaction?
What is the characteristic quantity changed by the interaction?
ˇ Social relations - spreading of information - knows or not
ˇ Internet - packet routing - travel times
ˇ Molecular networks - chemical reactions concentrations
The spread of epidemic disease
ˇ Many diseases spread through populations by contact
between infective and susceptible individuals
ˇ The pattern of the disease-causing contacts forms a network
ˇ Questions asked:
ˇ what is the typical size of an outbreak?
ˇ will an epidemic occur? outbreak affects a finite fraction
of the population
ˇ what determines the probability of an epidemic?
The fully mixed model
ˇ Assume that an infective individual is equally likely to spread
the disease to any other member of the population or