Infrastructures connecting people: A mechanistic model for terrestrial transportation networks

Terrestrial Transportation Infrastructures (TTIs) are shaped by both socio-political and geographical factors, hence encoding crucial information about how resources and power are distributed through a territory. Therefore, analysing the structure of pathway, railway or road networks allows us to gain a better understanding of the political and social organization of the communities that created and maintained them. Network science can provide extremely useful tools to address quantitatively this issue. Here, focussing on passengers transport, we propose a methodology to shed light on the processes and forces that moulded transportation infrastructures into their current configuration, without having to rely on any additional information besides the topology of the network and the distribution of the population. Our approach is based on a simple mechanistic model that implements a wide spectrum of decision-making mechanisms (representing different power distributions) which could have driven the growth of a TTI. Thus, by adjusting a few model parameters, it is possible to generate several synthetic transportation networks, and compare across them and against the empirical system under study. An illustrative case study (i.e. the railway system in Catalonia, a region in Spain) is also provided to showcase the application of the proposed methodology. Our preliminary results highlight the potential of our approach, thus calling for further research.