Ernesto Estrada, a research professor at the Higher Council for Scientific Research (CSIC) at the Institute of Interdisciplinary Physics and Complex Systems, has written a book titled “At the Mercy of the Networks”. In his work, Estrada explores the power of network analysis in understanding complex systems.
The success of science has historically been rooted in breaking down systems into their fundamental units. However, to truly comprehend complex structures, it is crucial to adopt a perspective that allows us to see the interconnectedness of elements. This is where network analysis comes in. By simplifying relationships between elements through mathematical objects known as networks or graphs, we can capture essential information from various real-life scenarios such as social relations, epidemics, anatomical structures, gene networks, metabolic or neuronal networks, social conflicts, and transportation networks.
Estrada discusses various mathematical models that simulate the formation of social networks and enable researchers to study real-life network structures. One such model created by mathematicians Paul Erdös and Alfred Rényi begins with a group of individuals who do not know each other. Whether or not a connection is formed between two nodes is determined by a random value compared to a threshold value. To determine if the simulation results resemble real-world social networks, one can analyze key characteristics such as network density, connectivity, and average length of pathways between elements. These properties shed light on how information flows within the network.
While Erdös and Rényi’s model accurately captures some aspects of social phenomena like high connectivity and low density in many real-world social networks, other models proposed by scientists like Steven Strogatz, Duncan Watts, Albert-Lazslo Barabási