The economic crises seems blinding the governments and major economic actors toward environmental troubles. Nevertheless, the impacts of population growth and economic expansion have now the potential to disrupt important regulatory functions of global ecological systems. Green growth involves transforming the production and consumption processes in order to maintain or restore these regulatory functions of the planet's natural capital. It requires that environmental facto rs be treated as an essential factor of production and not merely an externality.
This study uses social network analysis to model a contact network of people who inject drugs (PWID) relevant for investigating the spread of an infectious disease (hepatitis C). Using snowball sample data, parameters for an exponential random graph model (ERGM) including social circuit dependence and four attributes (location, age, injecting frequency, gender) are estimated using a conditional estimation approach that respects the structure of snowball sample designs. Those network parameter estimates are then used to create a novel, model-dependent estimate of network size.


