Graph theory
In 1736, Leonhard Euler created graph theory. Graph theory paved the way for network models such as Barabási-Albert's scale-free networks, chance networks such as Paul Erdös and Alfréd Rényi, Erdős–Rényi model, which applies to random graph theory, and Watts &amp; Strogatz Small-world network, all of which can be adapted to be representative of strategies and or relationships in the marketplace.